Index: E3-E4 Consumer Mobility Index

E3-E4 Consumer Mobility Index
INDEX
1 BASICS OF MOBILE COMMUNICATION .................................................... 2
2 MIGRATION TO MOBILE TECHNOLOGIES UPTO 5G ......................... 14
3 VARIOUS 3GPP RELEASES AND STANDARDS........................................ 26
4 VARIOUS PHASES OF BSNL CMTS TENDER ........................................... 53
5 BACKHAUL MEDIA FOR MOBILE RADIO NETWORK (OFC/ OFC

SYSTEMS/ MINI LINK) AND RRH ............................................................... 57
6 KPI REPORTS FOR 2G/3G/4G ....................................................................... 68
7 MOBILE SALES MANAGEMENT (BCCS, FRANCHISE MANAGEMENT,

SALES CHANNEL MANAGEMENT AND SANCHARSOFT) ................... 93
8 3G MOBILE NETWORK ............................................................................... 110
9 4G MOBILE NETWORK ............................................................................... 128
10 CONCEPT OF SON ......................................................................................... 138
11 NETWORK OPTIMIZATION USING DTT REPORTS AND SON DATA

MANAGEMENT .............................................................................................. 158
12 CNMS PORTAL AND MOBILE NOC.......................................................... 169
E3-E4 CM Version 3.0 April 2021 Page 1 of 178

For Restricted Circulation
E3-E4 Consumer Mobility Basics of Mobile Communication
1 BASICS OF MOBILE COMMUNICATION

1.1 LEARNING OBJECTIVES
On completion of this chapter trainee will be able to understand Basic of Mobile
communication. Topics covered will be:-
 Cellular concept
 Fundamentals of GSM
 GSM Architecture
1.2 CELLULAR CONCEPT
Traditional mobile service was structured similar to television broadcasting. One
very powerful transmitter located at the highest spot in an area would broadcast in a
radius of up to fifty kilometers. The Cellular concept structured the mobile telephone
network in a different way. Instead of using one powerful transmitter many low-powered
transmitter were placed throughout a coverage area. In a cellular system, the covering
area of an operator is divided into cells. A cell corresponds to the covering area of one
transmitter or a small collection of transmitters. The cellular concept employs variable
low power levels, which allows cells to be sized according to subscriber density and
demand of a given area. As the population grows, cells can be added to accommodate that
growth. Frequencies used in a cell will be reused several cells away. The distance
between the cells using the same frequency must be sufficient to avoid interference. The
frequency reuse will increase considerably the capacity in number of users.
1.2.1 CELL SYSTEM
A cell is the basic geographic unit of cellular system. The term cellular comes
from the honeycomb areas into which a coverage region is divided. Cells are base stations
transmitting over small geographic areas that are represented as hexagons as shown in
Figure. Each cell size varies depending upon landscape. Because of constraint imposed by
natural terrain and man-made structures, the true shape of cell is not a perfect hexagon. In
order to work properly, a cellular system must verify the following two main conditions:
The power level of a transmitter within a single cell must be limited in order to
reduce the interference with the transmitters of neighboring cells.
Neighboring cells can not share the same channels. In order to reduce the
interference, the frequencies must be reused only within a certain pattern.
Figure 1: Cell System

1.3 CLUSTER
The spectrum allocated for a cellular network is limited. As a result there is a limit
to the number of frequencies or channels that can be used. The cells are grouped into
clusters. Group of cells in which no frequencies are reused is termed as a cluster.
Figure 2: CLUSTER
1.3.1 TYPES OF CELLS
The density of population in a country is so varied that different types of cells are
used:
A. MACRO CELLS
The macro cells are large cells for remote and sparsely populated areas.
B. MICRO CELLS
These cells are used for densely populated areas. By splitting the existing areas
into smaller cells, the number of channels available is increased as well as the capacity of
the cells. The power level of the transmitters used in these cells is then decreased,
reducing the possibility of interference between neighboring cells.
C. PICO CELLS
Pico cells are small cells whose diameter is only few dozen meters; they are used
mainly in indoor applications. It can cover e.g. a floor of a building or an entire building
like shopping centers, Airports etc.
D. SELECTIVE CELLS
It is not always useful to define a cell with a full coverage of 360 degrees. In some
cases, cells with a particular shape and coverage are needed. These cells are called
selective cells. Typical examples of selective cells are the cells that may be located at the
entrances of tunnels where coverage of 360 degrees is not needed. In this case, a selective
cell with coverage of 120 degrees is used.
E. UMBRELLA CELLS
A freeway crossing very small cells produces an important number of handovers
among the different small neighboring cells in case of a fast moving mobile subscriber. In
order to solve this problem, the concept of umbrella cells is introduced. An umbrella cell
covers several micro cells. The power level inside an umbrella cell is increased
comparing to the power levels used in the micro cells that form the umbrella cell. When
the speed of the mobile is too high, the mobile is handed over to the umbrella cell. The
mobile will then stay longer in the same cell (in this case the umbrella cell). This will
reduce the number of handovers and the work of the network.

1.3.2 CELL SECTORING

One way of reducing the level of interference is to use directional antenna at base
stations, with each antenna illuminating a sector of the cell, and with a separate channel
set allocated to each sector. There are two commonly used methods of Sectorisation either
using 120˚ sector or 60˚ sector, both of which reduce the number of prime interference
sources.
f3
1
3 f1
2
f2
Figure 3: Sectorization
The three sector case is generally used with a seven cell pattern, giving an overall
requirement for 21 channel sets as shown in Figure.
1.3.3 FEATURES OF DIGITAL CELLULAR SYSTEM
A. SMALL CELLS: A cellular system uses many base stations with relatively
small coverage radii (on the order of a 100 m to 30 km).
B. FREQUENCY REUSEF: The spectrum allocated for a cellular network is
limited. As a result there is a limit to the number of channels or frequencies that can be
used. For this reason each frequency is used simultaneously by multiple base-mobile
pairs. This frequency reuse allows a much higher subscriber density per MHz of spectrum
than other systems.
C. SMALL, BATTERY-POWERED HANDSET: In addition to supporting
much higher densities than previous systems, this approach enables the use of small,
battery-powered handsets with a radio frequency that is lower than the large mobile units
used in earlier systems.
D. PERFORMANCE OF HANDOVERS: In cellular systems, continuous
coverage is achieved by executing a ―handover‖ (the seamless transfer of the call from
one base station to another) as the mobile unit crosses cell boundaries. This requires the
mobile to change frequencies under control of the cellular network.
1.4 FUNDAMENTALS OF GSM
A cellular mobile communications system uses a large number of low-power
wireless transmitters to create cells—the basic geographic service area of a wireless
communications system. Variable power levels allow cells to be sized according to the
subscriber density and demand within a particular region. As mobile users travel from cell
to cell, their conversations are "handed over" between cells in order to maintain seamless
service. Channels (frequencies) used in one cell can be reused in another cell some
distance away. Cells can be added to accommodate growth, creating new cells in
uncovered areas or overlaying cells in existing areas.
The important OBJECTIVES of the mobile communication are:-
 Any time Anywhere communication
 Mobility & Roaming
 High capacity & subs. Density
 Efficient use of radio spectrum

 Seamless Network Architecture

 Low cost
 Innovative Services
 Standard Interface
1.4.1 DIFFERENT GENERATIONS:
TECHNOLOGY 1G 2G 2.5G 3G 4G
First Design 1970 1980 1985 1990 2000
Implementation 1982 1991 1999 2002 2010?

IP-oriented
Broadband
Analog Digital Package unlimited
Service data up to
Voice Voice, SMS Data multimedia
2 Mb/s
data
TDMA, EVDO,
GPRS, WiMAX,
Standards AMPS CDMA, W-CDMA,
EDGE LTE
GSM HSDPA
Data Bandwidth 1.9 kbps 14.4 kbps 384 kbps 2 mbps 200 mbps
Table 1. Different Generations
Figure 4: Different Generations

Figure 5: Basic Mobile Telephone Service Network

1.4.2 DUPLEXING METHODOLOGY:
Duplexing is the technique by which the send and receive paths are separated over
the medium, since transmission entities (modulator, amplifiers, demodulators) are
involved.
There are two types of duplexing:
A) Frequency Division Duplexing FDD
B) Time Division Duplexing TDD
A. Frequency Division Duplexing (FDD)
Different Frequencies are used for send and receive paths and hence there will be
a Forward band and reverse band. Duplexer is needed if simultaneous transmission (send)
and reception (receive) methodology is adopted .Frequency separation between forward
band and reverse band is constant.
B. Time Division Duplexing (TDD)
TDD uses different time slots for transmission and reception paths. Single radio
frequency can be used in both the directions instead of two as in FDD. No duplexer is
required. Only a fast switching synthesizer, RF filter path and fast antenna switch are
needed. It increases the battery life of mobile phones.
GSM use Frequency Division Duplexing.
1.4.3 FREQUENCY BANDS AND CHANNEL ARRANGEMENT
STANDARD OR PRIMARY GSM 900 BAND,P-GSM
For Standard GSM 900 Band, the system is required to operate in the following
frequency band:
 890 - 915 MHz: Mobile Transmit, Base Receive
 935 - 960 MHz: Base Transmit, Mobile Receive
DCS 1800 Band: For DCS 1800
The system is required to operate in the following band:
 1710 - 1785 MHz: Mobile Transmit, Base Receive
 1805 - 1880 MHz: Base Transmit, Mobile Receive

Standard or Primary GSM 900 Band 1800 Band

Uplink Frequency 890-915 MHz 1710 - 1785 MHz
Downlink frequency 935-960 MHz 1805 – 1880 MHz
Duplex Distance 45 MHz 95 MHz
Carrier separation 200 KHz 200 KHz
Frequency Channels 124 374
Voice coder bit rate 13 Kbps 13 Kbps
Modulation GMSK GMSK
Air transmission Rate 270.8333 Kbps 270.8333 Kbps
Access Method FDMA/TDMA FDMA/TDMA
Speech Coder RPE-LTP RPE-LTP
Duplexing FDD FDD
1.5 GSM NETWORK STRUCTURE
Every telephone network needs a well-designed structure in order to route
incoming called to the correct exchange and finally to the called subscriber. In a mobile
network, this structure is of great importance because of the mobility of all its subscribers.
In the GSM system, the network is divided into the following partitioned areas.
 GSM service area
 PLMN service area
 MSC service area
 Location area
 Cells.
Figure 6: GSM- Network Structure

1.5.1 GSM NETWORK SYSTEM
GSM system basically designed as a combination of three major subsystems:
 Base Station Subsystem (BSS)
 Network Switching Subsystem (NSS)
 Operation Support Subsystem (OSS)

1.5.2 GSM NETWORK ELEMENTS

The major network elements are MS, Base Station Controller (BSC), Base
Transceiver Station (BTS) and Mobile Service Switching Centre (MSC) and the four
databases associated with MSC namely HLR, VLR, EIR and AUC.
Figure 7: GSM- Architecture

Mobile Station (MS)
The MS includes radio equipment and the SIM (Subscriber Identity Module) that
a subscribe needs in order to access the services provided by the GSM PLMN. The MS
may include provisions for data communication as well as voice. A mobile transmits and
receives message to and from the GSM system over the air interface to establish and
continue connections through the system.
Each MS (Mobile Equipment) is identified by an International Mobile Equipment
Identity (IMEI) that is permanently stored in the mobile unit. Upon request, the MS sends
this number over the signalling channel to the MSC. The IMEI can be used to identify
mobile units that are reported stolen or operating incorrectly.Just as the IMEI identities
the mobile equipment, other numbers are used to identify the mobile subscriber.The
Mobile Subscriber ISDN Number (MSISDN) is the number that the calling party dials in
order to reach the subscriber. It is used by the land network to route calls toward an
appropriate MSC. The international mobile subscribe identity (IMSI) is the primary
identity of the subscriber within the mobile network and is permanently assigned to him.
The GSM system can also assign a Temporary Mobile Subscriber Identity (TMSI) to
identity a mobile. This number can be periodically changed by the system and protect the
subscriber from being identified by those attempting to monitor the radio channel.
These are five different categories of mobile telephone units specified by the
European GSM system: 20W, 8W, 5W, 2W, and 0.8W. GSM subscribers are provided
with a SIM card with its unique identification at the very beginning of the service. By
divorcing the subscriber ID from the equipment ID, the subscriber may never own the
GSM mobile equipment set. The subscriber is identified in the system when he inserts the
SIM card in the mobile equipment. This provides an enormous amount of flexibility to
the subscribers since they can now use any GSM-specified mobile equipment. Thus with
a SIM card the idea of ―Personalize‖ the equipment currently in use and the respective
information used by the network (location information) needs to be updated. The smart
card SIM is portable between Mobile Equipment (ME) units. The user only needs to take
his smart card on a trip. He can then rent a ME unit at the destination, even in another

country, and insert his own SIM. Any calls he makes will be charged to his home GSM
account. Also, the GSM system will be able to reach him at the ME unit he is currently
using.
The SIM is a removable SC, the size of a credit card, and contains an integrated
circuit chip with a microprocessor, random access memory (RAM), and read only
memory (ROM). It is inserted in the MS unit by the subscriber when he or she wants to
use the MS to make or receive a call. As stated, a SIM also comes in a modular form that
can be mounted in the subscriber‘s equipment. When a mobile subscriber wants to use the
system, he or she mounts their SIM card and provide their Personal Identification Number
(PIN), which is compared with a PIN stored within the SIM. If the user enters three
incorrect PIN codes, the SIM is disabled.
Base Transceiver Station (BTS)
The BSS is a set of BS equipment (such as transceivers and controllers) that is in
view by the MSC through a single A interface as being the entity responsible for
communicating with MSs in a certain area. The radio equipment of a BSS may be
composed of one or more cells. A BSS may consist of one or more BS. The interface
between BSC and BTS is designed as an A-bis interface. The BSS includes two types of
machines: the BTS in contact with the MSs through the radio interface and the BSC, the
latter being in contact with the MSC. The function split is basically between transmission
equipment, the BTS, and managing equipment at the BSC. A BTS compares radio
transmission and reception devices, up to and including the antennas, and also all the
signal processing specific to the radio interface. A single transceiver within BTS supports
eight basic radio channels of the same TDM frame. A BSC is a network component in the
PLMN that function for control of one or more BTS. It is a functional entity that handles
common control functions within a BTS.
A BTS is a network component that serves one cell and is controlled by a BSC.
BTS is typically able to handle three to five radio carriers, carrying between 24 and 40
simultaneous communication. Reducing the BTS volume is important to keeping down
the cost of the cell sites.
An important component of the BSS that is considered in the GSM architecture as
a part of the BTS is the Transcoder/Rate Adapter Unit (TRAU). The TRAU is the
equipment in which coding and decoding is carried out as well as rate adoption in case of
data. Although the specifications consider the TRAU as a subpart of the BTS, it can be
sited away from the BTS (at MSC), and even between the BSC and the MSC.
The interface between the MSC and the BSS is a standardized SS7 interface (A-
interface) that, as stated before, is fully defined in the GSM recommendations. This
allows the system operator to purchase switching equipment from one supplier and radio
equipment and the controller from another. The interface between the BSC and a remote
BTS likewise is a standard the A-bis. In splitting the BSS functions between BTS and
BSC, the main principle was that only such functions that had to reside close to the radio
transmitters/receivers should be placed in BTS. This will also help reduce the complexity
of the BTS.
Base Station Controller (BSC)
The BSC, as discussed, is connected to the MSC on one side and to the BTS on
the other. The BSC performs the Radio Resource (RR) management for the cells under its
control. It assigns and release frequencies and timeslots for all MSs in its own area. The
BSC performs the inter-cell handover for MSs moving between BTS in its control. It also
reallocates frequencies to the BTSs in its area to meet locally heavy demands during peak
hours or on special events. The BSC controls the power transmission of both BSSs and
MSs in its area. The minimum power level for a mobile unit is broadcast over the BCCH.

The BSC provides the time and frequency synchronization reference signals broadcast by
its BTS. The BSC also measures the time delay of received MS signals relative to the
BTS clock. If the received MS signal is not centred in its assigned timeslot at the BTS,
The BSC can direct the BTS to notify the MS to advance the timing such that proper
synchronization takes place. The BSC may also perform traffic concentration to reduce
the number of transmission lines from the BSC to its BTS.
Mobile Switching Center (MSC)
The network and the switching subsystem together include the main switching
functions of GSM as well as the databases needed for subscriber data and mobility
management (VLR). The main role of the MSC is to manage the communications
between the GSM users and other telecommunication network users. The basic switching
function performed by the MSC is to coordinate setting up calls to and from GSM users.
The MSC has interface with the BSS on one side (through which MSC VLR is in contact
with GSM users) and the external networks on the other (ISDN/PSTN/PSPDN). The main
difference between a MSC and an Exchange in a fixed network is that the MSC has to
take into account the impact of the allocation of RRs and the mobile nature of the
subscribers and has to perform, in addition, at least, activities required for the location
registration and handover. The MSC is a telephony switch that performs all the switching
functions for MSs located in a geographical area as the MSC area. The MSC must also
handle different types of numbers and identities related to the same MS and contained in
different registers: IMSI, TMSI, ISDN number, and MSRN. In general identities are used
in the interface between the MSC and the MS, while numbers are used in the fixed part of
the network, such as, for routing.
As stated, the main function of the MSC is to coordinate the set-up of calls
between GSM mobile and PSTN users. Specifically, it performs functions such as paging,
resource allocation, location registration, and encryption. Specifically, the call-handling
function of paging is controlled by MSC. MSC coordinates the set-up of call to and from
all GSM subscribers operating in its areas. The dynamics allocation of access resources is
done in coordination with the BSS. More specifically, the MSC decides when and which
types of channels should be assigned to which MS. The channel identity and related radio
parameters are the responsibility of the BSS; The MSC provides the control of
interworking with different networks. It is transparent for the subscriber authentication
procedure. The MSC supervises the connection transfer between different BSSs for MSs,
with an active call, moving from one call to another. This is ensured if the two BSSs are
connected to the same MSC but also when they are not. In this latter case the procedure is
more complex, since more than one MSC in involved. The MSC performs billing on calls
for all subscribers based in its areas. When the subscriber is roaming elsewhere, the MSC
obtains data for the call billing from the visited MSC. Encryption parameters transfers
from VLR to BSS to facilitate ciphering on the radio interface are done by MSC. The
exchange of signalling information on the various interface toward the other network
elements and the management of the interface themselves are all controlled by the MSC.
Finally, the MSC serves as a SMS gateway to forward SMS messages from Short
Message Service Center (SMSC) to the subscribers and from the subscribers to the
SMSCs. It thus acts as a message mailbox and delivery system.
Visitor Location Register (VLR)
The VLR is collocated with an MSC. A MS roaming in an MSC area is controlled
by the VLR responsible for that area. When a MS appears in a LA, it starts a registration
procedure. The MSC for that area notices this registration and transfers to the VLR the
identity of the LA where the MS is situated. A VLR may be in charge of one or several
MSC LA‘s. The VLR constitutes the databases that support the MSC in the storage and

retrieval of the data of subscribers present in its area. When an MS enters the MSC area
borders, it signals its arrival to the MSC that stores its identity in the VLR. The
information necessary to manage the MS is contained in the HLR and is transferred to the
VLR so that they can be easily retrieved if so required. The data contained in the VLR
and in the HLR are more or less the same. Nevertheless the data are present in the VLR
only as long as the MS is registered in the area related to that VLR. Data associated with
the movement of mobile are IMSI, MSISDN, MSRN, and TMSI. The terms permanent
and temporary, in this case, are meaningful only during that time interval. Some data are
mandatory, others are optional.
Home Location Register (HLR)
The HLR is a database that permanently stores data related to a given set of
subscribers. The HLR is the reference database for subscriber parameters. Various
identification numbers and addresses as well as authentication parameters, services
subscribed, and special routing information are stored. Current subscriber status including
a subscriber‘s temporary roaming number and associated VLR if the mobile is roaming,
are maintained.
The HLR provides data needed to route calls to all MS-SIMs home based in its
MSC area, even when they are roaming out of area or in other GSM networks. The HLR
provides the current location data needed to support searching for and paging the MS-
SIM for incoming calls, wherever the MS-SIM may be. The HLR is responsible for
storage and provision of SIM authentication and encryption parameters needed by the
MSC where the MS-SIM is operating. It obtains these parameters from the AUC. The
HLR maintains record of which supplementary service each user has subscribed to and
provides permission control in granting services. The HLR stores the identification of
SMS gateways that have messages for the subscriber under the SMS until they can be
transmitted to the subscriber and receipt is knowledge. Some data are mandatory, other
data are optional. Both the HLR and the VLR can be implemented in the same equipment
in an MSC (collocated). A PLMN may contain one or several HLRs.
Authentication Center (AUC)
The AUC stores information that is necessary to protect communication through
the air interface against intrusions, to which the mobile is vulnerable. The legitimacy of
the subscriber is established through authentication and ciphering, which protects the user
information against unwanted disclosure. Authentication information and ciphering keys
are stored in a database within the AUC, which protects the user information against
unwanted disclosure and access. In the authentication procedure, the key Ki is never
transmitted to the mobile over the air path, only a random number is sent. In order to gain
access to the system, the mobile must provide the correct Signed Response (SRES) in
answer to a random number (RAND) generated by AUC.
Also, Ki and the cipher key Kc are never transmitted across the air interface
between the BTS and the MS. Only the random challenge and the calculated response are
transmitted. Thus, the value of Ki and Kc are kept secure. The cipher key, on the other
hand, is transmitted on the SS7 link between the home HLR/AUC and the visited MSC,
which is a point of potential vulnerability. On the other hand, the random number and
cipher key is supposed to change with each phone call, so finding them on one call will
not benefit using them on the next call. The HLR is also responsible for the
―authentication‖ of the subscriber each time he makes or receives a call. The AUC, which
actually performs this function, is a separate GSM entity that will often be physically
included with the HLR. Being separate, it will use separate processing equipment for the
AUC database functions.

Equipment Identity Register (EIR)

EIR is a database that stores the IMEI numbers for all registered ME units. The
IMEI uniquely identifies all registered ME. There is generally one EIR per PLMN. It
interfaces to the various HLR in the PLMN. The EIR keeps track of all ME units in the
PLMN. It maintains various lists of message. The database stores the ME identification
and has nothing do with subscriber who is receiving or originating call. There are three
classes of ME that are stored in the database, and each group has different characteristics.
 White List: contains those IMEIs that are known to have been assigned to
valid MS‘s. This is the category of genuine equipment.
 Black List: contains IMEIs of mobiles that have been reported stolen.
 Grey List: contains IMEIs of mobiles that have problems (for example,
faulty software, wrong make of the equipment, etc.). This list contains all
MEs with faults not important enough for barring.
Interworking Function (IWF)
GSM provides a wide range of data services to its subscribers. The GSM system
interface with various public and private data networks. It is the job of the IWF to provide
this interfacing capability. The IWF, which in essence is a part of MSC, provides the
subscriber with access to data rate and protocol conversion facilities so that data can be
transmitted between GSM Data Terminal Equipment (DTE) and a land-line DTE.
Echo Canceller (EC)
EC is used on the PSTN side of the MSC for all voice circuits. The EC is required
at the MSC PSTN interface to reduce the effect of GSM delay when the mobile is
connected to the PSTN circuit. The total round-trip delay introduced by the GSM system,
which is the result of speech encoding, decoding and signal processing, is of the order of
180 ms. Normally this delay would not be an annoying factor to the mobile, except when
communicating to PSTN as it requires a two-wire to four-wire hybrid transformer in the
circuit. This hybrid is required at the local switching office because the standard local
loop is a two-wire circuit. Due to the presence of this hybrid, some of the energy at its
four-wire receive side from the mobile is coupled to the four-wire transmit side and thus
retransmitted to the mobile. This causes the echo, which does not affect the land
subscriber but is an annoying factor to the mobile. The standard EC cancels about 70 ms
of delay. During a normal PSTN (land-to-land call), no echo is apparent because the
delay is too short and the land user is unable to distinguish between the echo and the
normal telephone ―side tones‖ However, with the GSM round-trip delay added and
without the EC, the effect would be irritating to the MS subscriber.
Operation and Maintenance Center
The OMC provides alarm-handling functions to report and log alarms generated
by the other network entities. The maintenance personnel at the OMC can define that
criticality of the alarm. Maintenance covers both technical and administrative actions to
maintain and correct the system operation, or to restore normal operations after a
breakdown, in the shortest possible time.
The fault management functions of the OMC allow network devices to be
manually or automatically removed from or restored to service. The status of network
devices can be checked, and tests and diagnostics on various devices can be invoked. For
example, diagnostics may be initiated remotely by the OMC. A mobile call trace facility
can also be invoked. The performance management functions included collecting traffic
statistics from the GSM network entities and archiving them in disk files or displaying
them for analysis. Because a potential to collect large amounts of data exists, maintenance
personal can select which of the detailed statistics to be collected based on personal

interests and past experience. As a result of performance analysis, if necessary, an alarm

can be set remotely.
The OMC provides system change control for the software revisions and
configuration data bases in the network entities or uploaded to the OMC. The OMC also
keeps track of the different software versions running on different subsystems of the
GSM.
1.5.3 GSM IDENTITIES
International Mobile Subscriber Identity (IMSI)
An IMSI is assigned to each authorized GSM user. It consists of a mobile country
code (MCC), mobile network code (MNC), and a PLMN unique mobile subscriber
identification number (MSIN). The IMSI is not hardware-specific. Instead, it is
maintained on a SC by an authorized subscriber and is the only absolute identity that a
subscriber has within the GSM system. The IMSI consists of the MCC followed by the
NMSI and shall not exceed 15 digits.
Temporary Mobile Subscriber Identity (TMSI)
A TMSI is a MSC-VLR specific alias that is designed to maintain user
confidentiality. It is assigned only after successful subscriber authentication. The
correlation of a TMSI to an IMSI only occurs during a mobile subscriber‘s initial
transaction with an MSC (for example, location updating). Under certain condition (such
as traffic system disruption and malfunctioning of the system), the MSC can direct
individual TMSIs to provide the MSC with their IMSI.
Mobile Station ISDN Number (MSISDN)
The MS international number must be dialled after the international prefix in order
to obtain a mobile subscriber in another country. The MSISDN numbers is composed of
the country code (CC) followed by the National Significant Number (NSN), which shall
not exceed 15 digits.
The Mobile Station Roaming Number (MSRN)
The MSRN is allocated on temporary basis when the MS roams into another
numbering area. The MSRN number is used by the HLR for rerouting calls to the MS. It
is assigned upon demand by the HLR on a per-call basis. The MSRN for PSTN/ISDN
routing shall have the same structure as international ISDN numbers in the area in which
the MSRN is allocated. The HLR knows in what MSC/VLR service area the subscriber is
located. At the reception of the MSRN, HLR sends it to the GMSC, which can now route
the call to the MSC/VLR exchange where the called subscriber is currently registered.
International Mobile Equipment Identity (IMEI)
The IMEI is the unique identity of the equipment used by a subscriber by each
PLMN and is used to determine authorized (white), unauthorized (black), and
malfunctioning (gray) GSM hardware. In conjunction with the IMSI, it is used to ensure
that only authorized users are granted access to the system. An IMEI is never sent in
cipher mode by MS.
1.6 CONCLUSION
Mobile Communication will always useful as it has mobility , the newer antenna
system MIMO will play very important role in modern day communication.

E3-E4 Consumer Mobility Migration to Mobile Technolgies Upto 5G
2 MIGRATION TO MOBILE TECHNOLOGIES UPTO 5G

2.1 LEARNING OBLECTIVE
After completion of this chapter participant will able to understand about:
 Migration upto 5G Network Architecture
 2G/3G Architecture
 LTE Radio Network E UTRAN
 LTE Network Elements
 5G Network Architecture
2.2 MOBILE GENERATIONS
 1 G - First Generation - Analog - Only mobile voice services - AMPS, NMT-
450, TACS etc. (Cellular Revolution)
 2 G - Second Generation - Digital - Mostly for voice services & data delivery
possible – GSM, CDMA (IS-95), DAMPS (IS-136), ETDMA, PDC etc
(Breaking Digital Barrier).
 3 G - Third Generation - Voice & Data - Mainly for data services where voice
services will also be possible (Breaking Data Barrier)
 4 G - Fourth Generation - The Fourth Generation of mobile communication
upgrade existing communication networks and is expected to provide a
comprehensive and secure IP based solution where facilities such as voice, data
and streamed multimedia will be provided to users on an "Anytime, Anywhere"
basis and at much higher data rates compared to previous generations.
 5 G - Fifth Generation -The most important for 5G technologies are 802.11
Wireless Local Area Networks (WLAN) and 802.16 Wireless Metropolitan
Area Networks (WMAN), Ad-hoc Wireless Personal Area Network (WPAN)
and Wireless networks for digital Communication.
2.3 OVERVIEW OF GPRS
The existing GSM networks are based on circuit switching techniques. For data
services that are based on Internet Protocol (IP) such as e-mail and web browsing, GSM
circuit switching is inefficient.
GSM Release '97 has introduced the General Packet Radio Service (GPRS) which
maintains the GSM BSS access technologies but provides packet switched data services
to the mobile station (MS).
2.3.1 GPRS STANDARDIZATION
The ETSI standardization work on GPRS Phase 1 was officially finalized in
Q1/1998. It includes point-to-point (PTP) services and the complete basic GPRS
infrastructure. Air interface, mobility management, security, limited QoS, SMS service,
GPRS support nodes, and the GPRS backbone are all part of Phase 1.
The ETSI standardization work on GPRS Phase 2 was frozen with GSM Release
99. Some work items were included in the GSM Release 98. Phase 2 adds additional
services like enhanced QoS support and point-to-multipoint (PTM) connections. Some
main point of GPRS phase 2 are the support of:
 IPv4 and IPv6
 BSS co-ordination of radio resource allocation for class A GPRS services
 Enhanced QoS support in GPRS
 Charging and billing for GPRS – AoC
 Charging and billing for GPRS – Pre-paid

 Point-to-multipoint (PTM) services

Access to ISPs and intranets in GPRS Phase 2, separation of GPRS bearer
establishment and ISP service environment set-up
In GSM Release 4 (frozen March 2001) and GSM Release 5 (frozen June 2002),
QoS enhancements for the GPRS backbone were introduced to support packet switched
real-time services (on the long run). This goes hand-in-hand with the introduction of the
IP Multimedia Subsystem (IMS). The Nokia IP Multimedia Subsystem can be combined
with terminals supporting downloadable applications, creating exciting opportunities for
application developers and operators to develop and offer new IP multimedia services in
GPRS and 3G networks. Further information on network details is available in the
architecture module.
At the end of the year 2002, more than 120 operators are commercially offering
GPRS and more than 40 operators are testing GPRS or building up a GPRS
Key points
GPRS uses a packet-based switching technique, which will enhance GSM data
services significantly, especially for bursts Internet/intranet traffic.
Some application examples:
 Bus, train, airline real-time information
 Locating restaurants and other entertainment venues based on current
Location
 Lottery
 E-commerce
 Banking
 E-mail
 Web browsing
The main advantages of GPRS for users:
 Instant access to data as if connected to an office LAN
 Charging based on amount of data transferred (not the time connected)
 Higher transmission speeds
The main advantages for operators:
 Fast network roll-out with minimum investment
 Excess voice capacity used for GPRS data
 Smooth path to 3G services
In circuit switching, each time a connection is required between two points, a link
between the two points is established and the needed resources are reserved for the use of
that single call for the complete duration of the call.
In packet switching, the data to be transferred is divided up into packets, which
are then sent through the network and re-assembled at the receiving end.
The GPRS network acts in parallel with the GSM network, providing packet
switched connections to the external networks. The requirements of a GPRS network are
the following:
The GPRS network must use as much of the existing GSM infrastructure with the
smallest number of modifications to it.
Since a GPRS user may be on more than one data session, GPRS should be able to
support one or more packet switched connections.

Figure 8: GPRS Architecture

To support the budgets of various GPRS users, it must be able to support different
Quality of Service (QoS) subscriptions of the user.
The GPRS network architecture has to be compatible with future 3rd and 4th
generation mobile communication systems.
It should be able to support both point-to-point and point-to-multipoint data
connections.
It should provide secure access to external networks.
Figure 9: GSM GPRS Architecture

Figure shows the architecture of a GPRS network. The GPRS system brings some
new network elements to an existing GSM network. These elements are:
 Packet Control Unit (PCU)
 Serving GPRS Support Node (SGSN): the MSC of the GPRS network
 Gateway GPRS Support Node (GGSN): gateway to external networks
 Border Gateway (BG): a gateway to other PLMN Intra-PLMN backbone:
an IP based network inter-connecting all the GPRS elements
 Charging Gateway (CG)
 Legal Interception Gateway (LIG)
 Domain Name System (DNS)

 Firewalls: used wherever a connection to an external network is required.

Not all of the network elements are compulsory for every GPRS network.
2.3.2 PACKET CONTROL UNIT (PCU)
The PCU separates the circuit switched and packet switched traffic from the user
and sends them to the GSM and GPRS networks respectively. It also performs most of the
radio resource management functions of the GPRS network. The PCU can be either
located in the BTS, BSC, or some other point between the MS and the MSC. There will
be at least one PCU that serves a cell in which GPRS services will be available. Frame
Relay technology is being used at present to interconnect the PCU to the GPRS core.
2.3.3 CHANNEL CODEC UNIT (CCU)
The CCU is realised in the BTS to perform the Channel Coding (including the
coding scheme algorithms), power control and timing advance procedures.
2.3.4 SERVING GPRS SUPPORT NODE (SGSN)
The SGSN is the most important element of the GPRS network. The SGSN of the
GPRS network is equivalent to the MSC of the GSM network. There must at least one
SGSN in a GPRS network. There is a coverage area associated with a SGSN. As the
network expands and the number of subscribers increases, there may be more than one
SGSN in a network. The SGSN has the following functions:
 Protocol conversion (for example IP to FR)
 Ciphering of GPRS data between the MS and SGSN
 Data compression is used to minimise the size of transmitted data units
 Authentication of GPRS users
 Mobility management as the subscriber moves from one area to another,
and possibly one SGSN to another
 Routing of data to the relevant GGSN when a connection to an external
network is required
 Interaction with the NSS (that is, MSC/VLR, HLR, EIR) via the SS7
network in order to retrieve subscription information
 Collection of charging data pertaining to the use of GPRS users
 Traffic statistics collections for network management purposes.
2.3.5 GATEWAY GPRS SUPPORT NODE (GGSN)
The GGSN is the gateway to external networks. Every connection to a fixed
external data etwork has to go through a GGSN. The GGSN acts as the anchor point in a
GPRS data connection even when the subscriber moves to another SGSN during roaming.
The GGSN may accept connection request from SGSN that is in another PLMN. Hence,
the concept of coverage area does not apply to GGSN. There are usually two or more
GGSNs in a network for redundancy purposes, and they back up each other up in case of
failure. The functions of a GGSN are given below:
 Routing mobile-destined packets coming from external networks to the
relevant SGSN
 Routing packets originating from a mobile to the correct external network
 Interfaces to external IP networks and deals with security issues
 Collects charging data and traffic statistics
 Allocates dynamic or static IP addresses to mobiles either by itself or with
the help of a DHCP or a RADIUS server

 Involved in the establishment of tunnels with the SGSN and with other
external networks and VPN.
From the external network's point of view, the GGSN is simply a router to an IP
sub-network. This is shown below. When the GGSN receives data addressed to a specific
user in the mobile network, it first checks if the address is active. If it is, the GGSN
forwards the data to the SGSN serving the mobile. If the address is inactive, the data is
discarded. The GGSN also routes mobile originated packets to the correct external
network.
2.4 THE EDGE
EDGE, or the Enhanced Data Rate for Global Evolution, is the new mantra in the
Global Internet Connectivity scene. EDGE is the new name for GSM 384. The
technology was named GSM 384 because of the fact that it provided Data Transmission
at a rate of 384 Kbps. It consists of the 8 pattern time slot, and the speed could be
achieved when all the 8 time slots were used. The idea behind EDGE is to obtain even
higher data rates on the current 200 KHz GSM carrier, by changing the type of the
modulation used.
Now, this is the most striking feature. EDGE, as being once a GSM technology,
works on the existing GSM or the TDMA carriers, and enables them to many of the 3G
services.
Although EDGE will have a little technical impact, since its fully based on GSM
or the TDMA carriers, but it might just get an EDGE over the upcoming technologies,
and of course, the GPRS. With EDGE, the operators and service providers can offer more
wireless data application, including wireless multimedia-mail (Web Based), Web
Infotainment, and above all, the technology of Video Conferencing. Now all these
technologies that were named earlier, were the clauses of the IMT-UMTS 3G Package.
But, with EDGE, we can get all these 3G services on our existing GSM phones, which
might just prove to be a boon to the user.
The current scenario clearly states that EDGE will definitely score higher than
GPRS. The former, allows its users to increase the data speed and throughput capacity, to
around 3-4 times higher than GPRS.
Secondly, it allows the existing GSM or the TDMA carriers to give the
sophisticated 3G services. And with 1600 Million subscribers of GSM in over 170
countries, offer the full Global Roaming, anywhere between India to Japan and to San
Fransisco.
 Based on an 8 PSK modulation, it allows higher bit rate across the air
Interface.
 One Symbol for every 3 bits. Thus, EDGE Rate = 3x GPRS Rate.
2.5 UMTS
 UMTS is evolution from GSM and other (2G) mobile systems TO 3G.
 UMTS will provide people with fast, unlimited access to information and
services at any time, from anywhere.
 UMTS is the convergence of mobile communications, Information
Technology (IT) and multimedia technologies.
 UMTS creates new opportunities for network operators, service providers
and content providers to generate revenue and seize market share.
 It provides interconnection with 2G networks as well as other terrestrial
And satellite-based networks.
 Supports numerous protocols and transport technologies

Table 2. 3GPP Releases

2.6 IMT-2000
2.6.1 INTRODUCTION TO IMT-2000
International Mobile Telecommunications –2000 (IMT-2000) is an initiative of
ITU that seeks to integrate the various satellite, terrestrial, fixed and mobile systems
currently being deployed and developed under a single standard or family of standards to
promote global service capabilities and interoperability after the year 2000.
These services are known as Third Generation or 3G services.
A future standard in which a single inexpensive mobile terminal can truly provide
communications any time, any where.
Limitations of 2G Systems
 Multiple Standards - No Global Standards
 No Common Frequency Band
 Low Data Bit Rates
 Low Voice Quality
 No Support of Video
 Various Network Systems to meet Specific Requirements
2.6.2 IMT-2000 OFFERS
The 3G networks must be capable of providing the following data rates 144 Kbps
at mobile speeds 384 Kbps at pedestrian speeds Mbps in fixed locations
3G systems will be capable of providing data rates up to 2 Mbps, in addition to
voice, fax services.
3G networks will offer the high resolution video and multimedia services on the
move such as mobile service, virtual banking, online billing, video conferencing etc.
2.6.3 IMT-2000 KEY FEATURES AND OBJECTIVES
 Incorporation of a variety of systems
 A high degree of commonality of design worldwide
 Compatibility of services within IMT-2000 and with the fixed network
 High quality and integrity comparable to the fixed network
 Use of small pocket terminal world wide

 Connection of mobile users to other mobile users or fixed users

 Provisioning of these services over wide range of user densities and
coverage areas.
 Efficient use of radio spectrum consistent with providing service at
acceptable cost.
 A modular structure which will allow the system to grow in size and
complexity
Provision of a framework for the continuing expansion of mobile network services
and access to services and facilities of the fixed network
An open architecture which will permit easy introduction of advances in
technology of different applications
2.6.4 IMT-2000 WILL PROVIDE..
 Enhanced voice quality, ubiquitous coverage and enable operators to
provide service at reasonable cost
 Increased network efficiency and capacity
 New voice and data services and capabilities
 An orderly evolution path from 2G to 3G systems to protect investments.
2.7 TERRESTRIAL RADIO INTERFACE SPECIFICATIONS
ITU NOMENCLATURE COMMONLY KNOWN AS TECHNOLOGY
IMT-DS UTRA-FDD W-CDMA

DIRECT SPREAD (UMTS TERRESTRIAL
RADIO ACCESS)
IMT-MC CDMA2000 1X & 2X CDMA
MULTI CARRIER
IMT-TC TIME CODE UTRA-TDD CDMA + TDMA
(UMTS TERRESTRIAL RADIO
ACCESS) AND
TD-SCDMA
IMT-SC UWV-136 TDMA

SINGLE CARRIER (UNIVERSAL WIRELESS
COMMUNICATIONS)
IMT-FT DECT TDMA + FDMA

FREQUENCY TIME
Table 3. ITU Nomenclature
2.8 MIGRATION PATH
While a multiplicity of 2G standards have been developed and deployed, the ITU
wanted to avoid a similar situation to develop for 3G.
Hence, the ITU Radio communication Sector (ITU-R) has elaborated on a
framework for a global set of 3G standards, which will facilitate global roaming by
operating in a common core spectrum and providing migration path to all the major
existing 2G technologies.

The major 2G Radio access networks are based on either cdma-One or GSM
technologies and different migration path is proposed for each of these technologies.
2.8.1 GSM TO 3G
GSM can be upgraded for higher data rate upto 115 Kbps through deploying
GPRS (General Packet Radio Service) network .This requires addition of two core
modules
 SGSN (Serving GPRS Service Node)
 GGSN (Gateway GPRS Service Node)
GSM radio access network is connected to SGSN through suitable interfaces.
GPRS phase-II will support higher data rates up to 384 Kbps through
incorporating EDGE (Enhanced Data Rate for GSM Evolution).
Further, to support data rates up to 2 Mbps, Third Generation radio access
network (3G RAN)
W-CDMA is deployed. 3G RAN is connected to GSM MSC for circuit oriented
services and to SGSN for packet oriented services (internet access). Therefore the
migration path can be represented as :
GSM GPRS EDGE W-CDMA.
2.8.2 CDMA ONE TO 3G
CDMA One progression towards higher speed data is in manageable steps. The
present data rate of 14.4 is upgradeable to 64 Kbps (IS-95B).
Still higher data rates are supported through third generation (3G) networks.
CDMA One supports a low risk and flexible phased evolution to 3G, called cdma2000.
The first step in this transition to CDMA 2000, also referred as 1xRTT (MC-
CDMA) enables delivering peak data rates of 144 Kbps for stationary and mobile
applications
Future evolutionary step will produce a harmonized 3xRTT (MC-CDMA)
solution expected to deliver peak data rates of up to 2 Mbps.
In addition, both 1xRTT and 3xRTT are backward compatible to CDMA One.
Therefore the migration path can be represented as:
CDMA One CDMA 2000 (MC-CDMA)
2.9 3G CELLULAR SYSTEMS
3G systems are planned with OBJECTIVES of integration of all kinds of wireless
systems into universal mobile telecommunication system. Work is continuing in
European research consortium, RACE, and in ETSI towards developing UMTS
(Universal Mobile Telecommunication System) on an joint European basis. At the same
time ITU is working globally towards IMT-2000 (International Mobile Communication-
2000) with mutual agreements and information exchange.
One of the main OBJECTIVES of 3G systems is that they will gather existing
mobile services (cellular, cordless, paging etc.) into one single network. The multiplicity
of services and features of the system will make it possible for the users to choose among
multiple terminals and service provides. Terminals will become smarter and will be able
to support several radio interface with the help of software radio technology. Among the
OBJECTIVES that have been assigned to 3G system designers are : voice quality as with
fixed networks, satellite services for non-covered areas, low terminal and services costs,
high bit rate mobile multi-media services (2 Mbps for indoor and reduced mobility users,
384 Kbps for urban outdoor , and 144 Kbps for rural outdoor), multiple services per user
(speech at 8 Kbps, data at 2,4 or 6 x 64=384 Kbps, video at 384 Kbps and multimedia,
security and antifraud features against access to data by non-authorized people or entities.

2.9.1 4G LONG-TERM EVOLUTION(LTE)

In 2004, 3GPP began a study into the long term evolution of UMTS.
The aim was to keep 3GPP‘s mobile communication systems competitive over
timescales of 10 years and beyond,
by delivering the high data rates and low latencies those future users would
require.
Evolution of the system architecture from GSM and UMTS to LTE.
Figure 10: Evolution of the system architecture from GSM and UMTS to LTE.
2.9.2 EVOLVED PACKET CORE (EPC)
 EPC is a direct replacement for the packet switched domain of UMTS and
GSM.
 It distributes all types of information to the user, voice as well as data,
using the packet switching technologies.
 There is no equivalent to the circuit switched domain.
 voice calls are transported using voice over IP.
 The evolved UMTS terrestrial radio access network (E-UTRAN) handles
the EPC‘s radio communications with the mobile.
2.9.3 EVOLVED PACKET SYSTEM (EPS)
The new architecture has two parts namely:
 System architecture evolution (SAE) which covered the core network,
 Long term evolution (LTE) which covered the radio access network, air
interface and mobile.

Figure 11: Evaluation Path Architecture

2.9.4 FEATURES OF LONG TERM EVOLUTION
 Downlink peak data rate is 100 Mbps
 Uplink data rate is to be 50 Mbps.
 Spectral efficiency of LTE is required to support three to four times greater
than that of Release 6 WCDMA in the downlink and two to three times
greater in the uplink.
 LTE is optimized for cell sizes up to 5 km.
 Latency is another important issue, particularly for time-critical
applications such as voice and interactive games.
2.9.5 TECHNICAL FEATURES OF LTE
Feature WCDMA LTE

Multiple access scheme WCDMA OFDMA and SC-FDMA
Frequency re-use 1 Flexible
Use of MIMO antennas From Release 7 Yes
Bandwidth 5 MHz 1.4, 3, 5, 10, 15 or 20 MHz
Frame duration 10 ms 10 ms
Transmission time interval 2 or 10 ms 1 ms
Modes of operation FDD and TDD FDD and TDD
Uplink timing advance Not required Required
Transport channels Dedicated and shared Shared
Uplink power control Fast Slow
Table 4. Technical Features of LTE

Figure 12: 5G will be Evolution or Revolution

2.10 LTE- ADVANCED
 Peak data rate of 1000 Mbps in the downlink, and 500 Mbps in the uplink.
 bandwidth of 100 MHz that is made from separate components of 20
MHz each.
 spectral efficiency 4.5 to 7 times greater than that of Release 6 WCDMA
on the downlink, and 3.5 to 6 times greater on the uplink.
 LTE-Advanced is designed to be backwards compatible with LTE.
2.11 5TH GENERATION MOBILE NETWORK (M2M & IOT)
2.11.1 DEFINITION
5G is an end-to-end ecosystem to enable a fully mobile and connected society. It
empowers value creation towards customers and partners, through existing and emerging
use cases, delivered with consistent experience, and enabled by sustainable business
models.
2.11.2 VISION OF 5G:
MT for 2020 and beyond‖, the capabilities of IMT-2020 are identified, to make
IMT-2020 more flexible, reliable and secure than previous IMT when providing diverse
services in the intended three usage scenarios,
 Enhanced mobile broadband (eMBB).
 Ultra-reliable and low-latency communications (URLLC),
 Massive machine type communications (mMTC).
Figure 13: 3GPP RAN Progress on “5G”.

2.11.3 FEATURES OF 5G:

 5G push the envelope of performance to provide much greater throughput,
 Much lower latency,
 Ultra-high reliability,
 Much higher connectivity density, and
 Higher mobility range.
 Capability to control a highly heterogeneous environment, and
 Capability to ensure security and trust, identity, and privacy.
Figure 14: 5G Architecture

2.11.4 LAYERS IN 5G NETWORK
 Infrastructure resource layer.
 Business enablement layer.
 Business application layer.
 E2E management and orchestration entity.
Figure 15: 5G Layers

2.12 CONCLUSION
The 5G Network is the need of hour , as 4G Network has reached to its maximum
capabilities and it is difficult to manage latency in it, 5G is required for AI services.

E3-E4 Consumer Mobility Various 3GPP Releases and Standards
3 VARIOUS 3GPP RELEASES AND STANDARDS

 3GPP Specifications
 HSAP and HSPA+ Standards
 Various releases
 HSPA and HSPA+ technology
 Migration to 4G
3.2 THIRD-GENERATION PARTNERSHIP PROJECT (3GPP)
The cellular technologies specified by 3GPP are the most widely deployed in the
world, with the number of users passing 5 billion. Third Generation Partnership Project
(3GPP) was formed by standards-developing organizations from all regions of the world.
This solved the problem of trying to maintain parallel development of aligned
specifications in multiple regions. The present organizational partners of 3GPP are ARIB
(Japan), CCSA (China), ETSI (Europe), ATIS (USA), TTA (Korea) and TTC (Japan).
ETSI (European Telecommunications Standards Institute) in early 1998 had
selected Wideband CDMA (WCDMA) as the technology for UMTS (Universal Mobile
Telecommunications System) in the paired spectrum (FDD) and TD-CDMA (Time
Division CDMA) for the unpaired spectrum (TDD). There was also a decision to
harmonize the parameters between the FDD and the TDD components.
3GPP consists of several Technical Specifications Groups (TSGs). 3GPP TSG
RAN is the technical specification group that has developed WCDMA, its evolution
HSPA, as well as LTE, and is in the forefront of the technology.
Figure 16: 3GPP organization.
TSG RAN consists of five working groups (WGs):

 RAN WG1 dealing with the physical layer specifications.

 RAN WG2 dealing with the layer 2 and layer 3 radio interface
specifications.
 RAN WG3 dealing with the fixed RAN interfaces, for example interfaces
between nodes in the RAN, but also the interface between the RAN and
the core network.
 RAN WG4 dealing with the radio frequency (RF) and radio resource
management (RRM) performance requirements.
 RAN WG5 dealing with the terminal conformance testing.
The work in 3GPP is carried out with relevant ITU recommendations in mind and
the result of the work is also submitted to ITU. The organizational partners are obliged to
identify regional requirements that may lead to options in the standard. Examples are
regional frequency bands and special protection requirements local to a region. The
specifications are developed with global roaming and circulation of terminals in mind.
This implies that many regional requirements in essence will be global requirements for
all terminals, since a roaming terminal has to meet the strictest of all regional
requirements. Regional options in the specifications are thus more common for base
stations than for terminals.
The specifications of all releases can be updated after each set of TSG meetings,
which occur 4 times a year. The 3GPP documents are divided into releases, where each
release has a set of features added compared to the previous release. The features are
defined in Work Items agreed and undertaken by the TSGs. The releases up to Release 17
and some main features of those are shown in Figure. The date shown for each release is
the day the content of the release was frozen. For historical reasons, the first release is
numbered by the year it was frozen (1999), while the following releases are numbered 4,
5, etc. For the WCDMA Radio Access developed in TSG RAN, Release 99 contains all
features needed to meet the IMT-2000 requirements as defined by ITU. There are circuit-
switched voice and video services, and data services over both packet switched and
circuit-switched bearers. The first major addition of radio access features to WCDMA is
Release 5 with High Speed Downlink Packet Access (HSDPA) and Release 6 with
Enhanced Uplink. With HSPA, UTRA goes beyond the definition of a 3G mobile system
and also encompasses broadband mobile data. With the studies of an Evolved UTRAN
(LTE) and the related System Architecture Evolution (SAE), further steps are taken in
terms of broadband capabilities.
Figure 17: Releases of 3GPP specifications for UTRA

3.3 3GPP SPECIFICATIONS:
3GPP specifications are the actual documents that define the system. At a high
level, the specifications are organized into releases, each of which is a version of the
system with a particular set of features. 3GPP maintains the specifications for all the
releases of UMTS in parallel. This allows it to add new features to the system as part of

each new release, while making the occasional technical correction to the older, more
stable releases that are used by manufacturers. Each release is developed over a period of
months or even years, but the most important event happens when the release is frozen.
After it has been frozen, there are no more changes to a release‘s technical features,
although some issues such as the details of the protocols and the conformance tests will
usually lag behind. Technical corrections can of course continue for a long time after
freezing. The first release of UMTS was release99, which was frozen in March 2000.
This release specified a 3G telecommunication system based on the core network of
GSM, but with a new air interface that used wideband code division multiple access (W-
CDMA).The plan was then to have one release per year, using a numbering scheme of
release00, release 01 and so on. However, it was soon realized that this was too
ambitious, so the numbering scheme was changed to uncouple it from the calendar year,
and the next release became known as release 4. Using this scheme, release99 is
synonymous with release3, while the numbers1 and 2 are reserved for draft specifications.
Within each release, the different specifications are organized into series, each of
which covers a different part of the system. Series 21 to 36 describe UMTS, including
aspects of the system that are common with GSM. Other series refer to features that are
unique to GSM: series 00 to 13 were used up to release 99, and series 41 to 55 are for
release 4 onwards. Individual specifications have document numbers like (for example)
TS 25.331 v 6.12.0. Here, TS stands for technical specification – there are also documents
that do not actually define any part of the system, which are known as technical reports
and denoted TR; 25 is the series number; 331 is the specification number within that
series; 6 is the release number; 12 is the technical version number (which is incremented
after technical changes to a specification); and 0 is the editorial version number
(incremented after non-technical changes). This particular specification describes the
radio resource control (RRC) protocol.
There are several hundred specifications altogether, which can be downloaded
from the 3GPP website, www.3gpp.org.
3.4 HSPA AND HSPA+
We are at the dawn of a new decade that will bring to mass market the mobile
broadband innovations introduced over the last several years. 3G technology has shown
us the power and potential of always-on, everyplace network connectivity and has ignited
a massive wave of industry innovation that spans devices, applications, Internet
integration, and new business models. Already used by hundreds of millions of people,
mobile broadband connectivity is on the verge of becoming ubiquitous. It will do so on a
powerful foundation of networking technologies, including GSM with EDGE, HSPA, and
LTE. Through constant innovation, Universal Mobile Telecommunications System
(UMTS) with High Speed Packet Access (HSPA) technology has established itself as the
global, mobile broadband solution. Building on the phenomenal success of Global System
for Mobile Communications (GSM), the GSM-HSPA ecosystem has become the most
successful communications technology family ever. Through a process of constant
improvement, the GSM family of technologies has not only matched or exceeded the
capabilities of all competing approaches, but has significantly extended the life of each of
its member technologies.
UMTS-HSPA, in particular, has many key technical and business advantages over
other mobile wireless technologies. Operators worldwide are now deploying both High
Speed Downlink Packet Access (HSDPA) and High Speed Uplink Packet Access
(HSUPA), the combination of the two technologies called simply HSPA. HSPA is the
most capable cellular data technology ever developed and deployed. HSPA, already
widely available, follows the successful deployment of UMTS networks around the world

and is now a standard feature. HSPA is strongly positioned to be the dominant mobile-
data technology for the next five to ten years. To leverage operator investments in HSPA,
the 3GPP (Third Generation Partnership Project) standards body has developed a series of
enhancements to create ―HSPA Evolution,‖ also referred to as ―HSPA+.‖ HSPA
Evolution represents a logical development of the Wideband Code Division Multiple
Access (WCDMA) approach.
Table 5. Characteristics of 3GPP Technologies

The development of GSM and UMTS-HSPA happens in stages referred to as
3GPP releases, and equipment vendors produce hardware that supports particular versions
of each specification. It is important to realize that the 3GPP releases multiple

technologies. For example, Release 17 optimized efficiency and performance of 5G NR,

but also significantly enhanced GSM data functionality with Evolved EDGE. A summary
of the different 3GPP releases is as follows:
 Release 99: First deployable version of UMTS. Enhancements to GSM data
(EDGE). Majority of deployments today are based on Release 99.Provides
support for GSM/EDGE/GPRS/WCDMA radio-access networks.
 Release 4: Multimedia messaging support. First steps toward using IP transport in
the core network.
 Release 5: HSDPA First phase of IMS. Full ability to use IP-based transport
instead of just Asynchronous Transfer Mode (ATM) in the core network.
 Release6:HSUPA Enhanced multimedia support through Multimedia
Broadcast/Multicast Services (MBMS). Performance specifications for
advanced receivers. WLAN integration option. IMS enhancements. Initial
VoIP capability.
 Release 7: Provides enhanced GSM data functionality with Evolved EDGE.
Specifies HSPA Evolution (HSPA+), which includes higher order
modulation and MIMO. Provides fine-tuning and incremental
improvements of features from previous releases. Results include
performance enhancements, improved spectral efficiency, increased
capacity, and better resistance to interference. Continuous Packet
Connectivity (CPC) enables efficient ―always-on‖ service and enhanced
uplink UL VoIP capacity, as well as reductions in call set-up delay for
PoC. Radio enhancements to HSPA include 64 QAM in the downlink DL
and 16 QAM in the uplink. Also includes optimization of MBMS
capabilities through the multicast/broadcast, single-frequency network
(MBSFN) function.
 Release 8: Comprises further HSPA Evolution features such as simultaneous use
of MIMO and 64 QAM. Includes work item for dual-carrier HSPA (DC-
HSPA) wherein two WCDMA radio channels can be combined for a
doubling of throughput performance. Specifies OFDMA-based 3GPP
LTE. Defines EPC.
 Release 9: It includes HSPA and LTE enhancements including HSPA multi-
carrier operation.
 Release 10: Under development. Likely by 2011. Will specify LTE-Advanced that
meets the requirements set by ITU‘s IMT-Advanced project.
 Release 11: Advanced IP Interconnection of Services. Service
layer interconnection between national operators/carriers as well as third
party application providers. Heterogeneous networks (HetNet)
improvements, Coordinated Multi-Point operation (CoMP). In-device Co-
existence (IDC).
 Release 12: Enhanced Small Cells (higher order modulation, dual connectivity,
cell discovery, self-configuration), Carrier aggregation (2 uplink carriers, 3
downlink carriers, FDD/TDD carrier aggregation), MIMO (3D channel
modeling, elevation beam forming, massive MIMO), New and Enhanced
Services (cost and range of MTC, D2D communication, eMBMS
enhancements).
 Release 13: LTE in unlicensed, LTE enhancements for Machine-Type
Communication. Elevation Beam forming / Full-Dimension
MIMO, Indoor positioning. LTE-Advanced Pro.

 Release 14: Energy Efficiency, Location Services (LCS), Mission Critical Data
over LTE, Mission Critical Video over LTE, Flexible Mobile Service
Steering (FMSS), Multimedia Broadcast Supplement for Public Warning
System (MBSP), enhancement for TV service, massive Internet of Things,
Cell Broadcast Service (CBS).
 Release 15: First NR ("New Radio") release. Support for 5G Vehicle-to-x service,
IP Multimedia Core Network Subsystem (IMS), Future Railway Mobile
Communication System.
 Release 16: The 5G System - Phase 2: 5G enhancements, NR-based access to
unlicensed spectrum (NR-U), Satellite access.
 Release 17: TSG RAN: Several features that continue to be important for overall
efficiency and performance of 5G NR: MIMO, Spectrum Sharing
enhancements, UE Power Saving and Coverage Enhancements. RAN1 will
also undertake the necessary study and specification work to enhance the
physical layer to support frequency bands beyond 52.6GHz, all the way up
until 71 GHz.
TSG SA groups focused on further enhancements to the 5G system and enablers
for new features and services:
Enhanced support of: non-public networks, Industrial Internet of Things, edge
computing in 5GC, access traffic steering, switch and splitting support, network
automation for 5G, network slicing, advanced V2X service, devices having multiple
USIMs, proximity-based services in 5GS,5G multicast-broadcast services, Unmanned
Aerial Systems (UAS), satellite access in 5G, 5GC location services, Multimedia Priority
Service.
3.5 UMTS EVOLUTIONTO LTE:
The evolution of UMTS-HSPA happens in stages referred to as 3GPP Releases. A
summary of the different 3GPP releases towards LTE is as follows:
Figure 18: 3GPP UMTS Evolution

3.6 LTE
LTE (Long Term Evolution) is the project name given to development of a high
performance air interface for cellular mobile communication systems. It is the last step

toward the 4th generation (4G) of radio technologies designed to increase the capacity
and speed of mobile telephone networks.
It was 3GPP release 8 when LTE was introduced for the very first time. All the
releases following only enhanced the technology. Based on release 8 standardization,
following were the main achievements.
 High peak data rates : Up to 300 Mbps in downlink and 75 Mbps in uplink when
using 4x4 MIMO and 20 MHz bandwidth
 High spectral efficiency
 Flexible bandwidths: 1.4 MHz, 3 MHz, 5 MHz, 10 MHz, 15 MHz and 20 MHz
 Short round trip time: 5 ms latency for IP packets in ideal radio conditions
 Simplified Architecture
 OFDMA in downlink and SC-FDMA in uplink
 All IP network
 MIMO Multiple Antenna Scheme
 Operation in paired (FDD) and unpaired spectrum (TDD)
Figure 19: Evolution to LTE

3.7 LTE ENHANCEMENT:
The initial enhancements were included to LTE in release 9. These were in fact
the improvements which were left behind from release 8 or perhaps provided some minor
improvements. These improvements are listed below with brief description.

Figure 20: 3GPP LTE Enhancement

3.8 4G : LTE ADVANCED
The basic LTE, long term evolution cellular services were launched around 2010
with some advance deployments well before this. It was never envisaged that this initial
form of LTE would provide the full performance intended. This required some additional
elements that were in what was termed LTE Advanced.
LTE Advanced, LTE-A incorporated a number of new techniques that enabled the
system to provide very much higher data rates, and also much better performance,
particularly at cell edges and other areas where performance would not normally have
been so good.
LTE Advanced took a few more years to fully develop and roll out across the
networks, but when introduced it enabled its many advanced features to provide
significant improvements over basic LTE.
Following are some significant improvements in release 10.
Enhanced Uplink multiple accesses: Release 10 introduces clustered SC-FDMA in
uplink. Release 8 SC-FDMA only allowed carriers along contiguous block of spectrum
but LTE-Advanced in release 10 allows frequency-selective scheduling in uplink
MIMO enhancements: LTE-Advanced allows upto 8x8 MIMO in downlink and on the
UE side it allows 4X4 in uplink direction.

Figure 21: MIMO Enhancement

Relay Nodes: In order to decrease coverage loop holes, Relay nodes are one of the
features proposed in release 10. The relay nodes or low power ends extending the
coverage of main eNB in low coverage environment. The relay nodes are connected to
Donor eNB (DeNB) through Un interface.
Figure 22: Relay Node

Carrier Aggregation (CA):
CA introduced in release 10 is a cost effective way for operators to utilize their
fragmented spectrum spread across different or same bands in order to improve end user
throughput as required by IMT-Advanced. Carrier Aggregation increases the channel
bandwidth by combining multiple RF carriers. Each individual RF carrier is known as a
Component Carrier.

Figure 23: Carrier Aggregation

The release 10 version of the 3GPP specifications defines signalling to support up
to 5 Component Carriers. i.e. a maximum combined channel bandwidth of 100 MHz.
Component Carriers do not need to be adjacent and can be located in different operating
bands. The release 10 version of the 3GPP specifications defines individual Component
Carriers to be backwards compatible so they can be used by release 8 and release 9
devices.
Support for Heterogeneous Networks:
The combination of large macro cells with small cells results in heterogeneous
networks. Release 10 intended to layout the detail specification for heterogeneous
networks.
Figure 24: Network Architecture Evolution

Enhanced inter-cell interference coordination (eICIC)

eICIC introduced in 3GPP release 10 to deal with interference issues in

Heterogeneous Networks (HetNet). eICIC mitigates interference on traffic and control
channels. eICIC uses power, frequency and also time domain to mitigate intra-frequency
interference in heterogeneous networks.
Figure 25: eICIC
Coordinated Multi-Point transmission (CoMP) :Coordinated Multi-Point (CoMP)

transmission in the down link and reception in the uplink are LTE-Advanced solutions to
help improve the cell edge throughput and spectrum efficiency performance.
Figure 26: Coordinated Multi-Point transmission

SON Improvements: Release 10 provides enhancements to SON features introduced in
release 9 which also considers self healing procedures.

3.9 ENHANCEMENT TO LTE ADVANCE (REL 11)

Release 11 includes enhancements to LTE Advanced features standardized in
release 10. Some of the important enhancements are listed below .
Carrier Aggregation enhancements: Following are the major enhancements to

carrier aggregation in release 11
 Multiple timing advances (TAs) for uplink carrier aggregation
 Non contiguous intra band carrier aggregation
 physical layer changes for carrier aggregation support in TDD LTE
Coordinated multipoint transmission and reception (CoMP): With CoMP the

transmitter can share data load even if they are not collocated. Though they are connected
by high speed fiber link
ePDCCH: New enhanced PDCCH introduced in 3GPP release 11 to increase

control channel capacity. ePDCCH uses PDSCH resources for transmitting control
information unlike release 8 PDCCH which can only use control region of subframes
Network based Positioning: In release 11, support for uplink positioning is

added by utilizing Sounding reference signals for time difference measurements taken by
many eNBs.
Minimization of drive test (MDT): Drive tests are always expensive. To

decrease dependency on drive tests, new solutions introduced which are independent of
SON though much related. MDT basically relies on information provided by UE.
RAN overload control for Machine type communication: For machine type
devices new mechanism has been specified in release 11 where network in case of mass
communication from devices can bar some devices to send connection request to network
In Device Co Existence: Now a days, all mobile devices would usually carry
multi radio transceivers like for LTE, 3G, Bluetooth, WLAN etc. Now this co existence
results in interference. To mitigate this interference, release 11 has specified solutions as
mentioned below
 DRX based time domain solutions
 Frequency domain solutions
 UE autonomous denials
Smartphone Battery saving technique: Many applications on smart phones

generate background traffic which consumes battery power. Release 11 specifies a
method where UE can inform network whether it needs to be operated in battery saving
mode or normal mode and based on UE request network can modify DRX parameters

3.10 FURTHER ENHANCEMENT TO LTE ADVANCED (REL 12)

Release 12 includes further enhancement to LTE Advanced features standardized
in release 10 and 11. Some of the important enhancements are listed below
Small cells enhancements: Small cells were supported since beginning with
features like ICIC and eICIC in release 10. Release 12 introduces optimization and
enhancements for small cells including deployments in dense areas. Dual connectivity i.e.
inter-site carrier aggregation between macro and small cells is also a focus area
Carrier aggregation enhancements: Release 12 now allows carrier aggregation

between co-located TDD and FDD carriers. In addition to carrier aggregation between
TDD and FDD, there are also now three carrier aggregations possible for total of 60 Mhz
spectrum aggregated
Machine Type communication (MTC): Huge growth is expected in machine

type communication in coming years which can result in tremendous network signalling,
capacity issues. To cope with this, new UE category is defined for optimized MTC
operations
Wifi integration with LTE: With integration between LTE and Wifi, operators
will have more control on managing WiFi sessions. In release 12, the intent is to specify
mechanism for steering traffic and network selection between LTE and WiFI
LTE in unlicensed spectrum: An LTE operation in unlicensed spectrum is one

of the study items in release 12. Operations in Bandwidth rich unlicensed spectrum brings
many benefits to operators like increase in network capacity, load and performance
3.11 RELEASE 13 AND BEYOND: LTE ADVANCED PRO
3GPP publishes its specifications in the form of releases. These releases are
published regularly. A new release is published when a set of essential new features are
developed and finalized. Often a set of such releases is given a marketing name. As
shown in Figure, Rel. 8, 9 is called LTE; Rel. 10, 11, 12, LTE-Advanced; and Rel. 13 and
beyond, LTE-A Pro.
LTE-A Pro is the marketing name for a set of releases that cellular standards body
3GPP (3rd Generation Partnership Project) publishes.3GPP has devised a set of advanced
features to continue enhancing the capabilities of 4G LTE as part of Rel. 13 and onwards.
This upgrade in capabilities has been called ―LTE-Advanced Pro (LTE-A Pro),‖ which
you may also see referred to as 4.5G or Pre-5G.
Figure 27: LTE Advanced PRO

Some of the important enhancements are listed below

Carrier aggregation enhancements: The goal in release 13 is to support carrier

aggregation of upto 32 CC (component carriers) where as in release 10, the carrier
aggregation was introduced with support of only upto 5 CC.
Enhancements for Machine-Type communication (MTC): Continuing from

release 12, there are further enhancements in MTC, a new low complexity UE category is
being defined to provide support for reduced bandwidth, power and support long battery
life.
LTE in unlicensed enhancements: The focus in release 13 is the aggregation of

primary cell from licensed spectrum with secondary cell from unlicensed spectrum to
meet the growing traffic demand
Indoor Positioning: In release 13 there is work going on improving existing

methods of indoor positioning and also exploring new positioning methods to improve
indoor accuracy
Enhanced multi-user transmission techniques: Release 13 also covers potential

enhancements for downink multiuser transmission using superposition coding
MIMO enhancements: Upto 8 antenna MIMO systems are currently supported,

the new study in this release will look into high-order MIMO systems with up to 64
antenna ports.
3.12 BEYOND REL. 13
5G NR and LTE-A Pro are evolved in parallel. Rel. 15 introduces 5G NR, a new
unified radio interface that significantly improves performance, efficiency and scalability
of cellular networks.
Figure 28: 5G NR and LTE-A Pro are evolving in parallel

3.13 INTRODUCTION TO 5G
5G is the 5th generation mobile network. It is a new global wireless standard after
1G, 2G, 3G, and 4G networks. 5G enables a new kind of network that is designed to

connect virtually everyone and everything together including machines, objects, and
devices.
5G wireless technology is meant to deliver higher multi-Gbps peak data speeds,
ultra low latency, more reliability, massive network capacity, increased availability, and a
more uniform user experience to more users. Higher performance and improved
efficiency empower new user experiences and connects new industries.
3.14 5G STANDARDIZATION
As of 3G, the generational designation corresponds to a standard defined by the
3rd Generation Partnership Project (3GPP). Even though its name has ―3G‖ in it, the
3GPP continues to define the standards for 4G and 5G, each of which corresponds to a
sequence of releases of the standard. Release 15 is considered the demarcation point
between 4G and 5G. Complicating the terminology, 4G was on a multi-release
evolutionary path referred to as Long Term Evolution (LTE). 5G is on a similar
evolutionary path, with several expected releases over its lifetime.5G is defined by ITU-R
as IMT-2020.
Figure 29: 5G Standardisation

3.15 5G PERFORMANCE TARGET
As the preliminaries for the work for the new 5G mobile communications system,
the outline requirements were set in place. These were defined by the ITU as part of
IMT2020. ITU defined 5G requirements in terms of 8 parameters:
 A peak rate up to 20 Gbps per user,
 User experienced rate of 100 Mbps,
 Mobility support to 500 km/h,
 A latency of 1 ms,
 A density of a million connections per m2,
 Energy efficiency 100× of 4G
 Area Traffic Capacity 10 Mbits/sec/m2
 Spectral Efficiency 3 X of 4G

Figure 30: 5G Performance Target
3.16 5G KEY APPLICATION AREAS

The ITU-R has defined three main application areas for the enhanced capabilities
of 5G. Enhanced Mobile Broadband (eMBB), Ultra Reliable Low Latency
Communications (URLLC), and Massive Machine Type Communications (mMTC). Only
eMBB is deployed in 2020; URLLC and mMTC are several years away in most locations.
Figure 31: 5G Application Area

Enhanced Mobile Broadband (eMBB)
Uses 5G as a progression from 4G LTE mobile broadband services, with faster
connections, higher throughput, and more capacity. This will benefit areas of higher
traffic such as stadiums, cities, and concert venues.
Ultra-Reliable Low-Latency Communications (URLLC)

Human and Machine centric communication. URLLS refer to using the network
for mission critical applications that require uninterrupted and robust data exchange.
Vehicle-to-Vehicle communication, Industrial IoT, 3D Gaming are use case of URLLC.
Massive Machine-Type Communications (mMTC)
Machine-centric communication.MMTC would be used to connect to a large
number of devices. 5G technology will connect some of the 50 billion connected IoT
devices. Most will use the less expensive Wi-Fi. Drones, transmitting via 4G or 5G, will
aid in disaster recovery efforts, providing real-time data for emergency responders. Most
cars will have a 4G or 5G cellular connection for many services. Autonomous cars do not
require 5G, as they have to be able to operate where they do not have a network
connection.
3.17 5G NEW RADIO:
5G NR or 5G New Radio is the new radio air interface being developed for 5G
mobile communications. With the demanding requirements being placed upon the new
5G mobile communications standard, a totally new radio interface and radio access
network has been developed Called 5G New Radio or 5G NR.
The development of the 5G NR or 5G New Radio is key to enabling the 5G

mobile communications system to work and it provides a number of significant
advantages when compared to 4G.
5G NR has been developed from scratch taking the requirements and looking at
the best technologies and techniques that will be available when 5G starts to be deployed.
5G NR utilises modulation, waveforms and access technologies that will enable

the system to meet the needs of high data rate services, those needing low latency and
those needing small data rates and long battery lifetimes amongst others. The first
iteration of 5G NR appeared in 3GPP Release 15.
3.17.1 5G NR SPECTRUMS
The 5G new radio, 5G NR utilises a variety of different frequency bands. Like the
other mobile communications systems, the frequency allocations are located in a variety
of areas of the radio spectrum.
Frequency Range
Two different frequency ranges are available for the 5G technology and the
different ranges have been designated FR1 - frequency range 1 and FR2 - frequency range
2. The bands in frequency range 1, FR1 are envisaged to carry much of the traditional
cellular mobile communications traffic.
The higher frequency bands in range FR2 are aimed at providing short range very
high data rate capability for the 5G radio. With 5G wireless technology anticipated to
carry much higher speed data, the additional bandwidth of these higher frequency bands
will be needed.
Originally the FR1 band was intended to define bands below 6 GHz, but with
anticipated additional spectrum allocations, the FR1 range has now been extended to
7.125 GHz.

FREQUENCY RANGES, FR1 & FR2 FOR 5G NR
FREQUENCY RANGE DESIGNATION FREQUENCY RANGE (MHZ)

FR1 410 - 7125
FR2 24 250 - 52600
Figure 32: 5G Frequency Range

3.17.2 5G DUPLEXING MODE
Frequency Range 1 includes operating bands which support Frequency Division

Duplexing (FDD), Time Division Duplexing (TDD),Supplemental Downlink (SDL) and
Supplemental Uplink (SUL).
Whereas Frequency Range 2 supports only TDD. 3GPP has specified

mechanisms to allow dynamic changes to the uplink and downlink transmission pattern
used by TDD. FR2 24 250 - 52600
3.17.3 5G FREQUENCY BANDS

5G FR1 FREQUENCY BANDS
5G NR UPLINK BAND DOWNLINK BAND DUPLEX
FREQUENCY (MHZ) (MHZ) MODE
BAND
n1 1920 - 1980 2110 - 2170 FDD
n2 1850 - 1910 1930 - 1990 FDD
n3 1710 - 1785 1805 - 1880 FDD
n5 824 - 849 869 - 894 FDD
n7 2500 - 2570 2620 - 2690 FDD
n8 880 - 915 925 - 960 FDD
n12 699 - 716 729 - 746 FDD
n20 832 - 862 791 - 821 FDD
n25 1850 - 1915 1930 - 1995 FDD
n28 703 - 748 758 - 803 FDD

n34 2010 - 20225 TDD

n38 2570 - 2620 TDD
n39 1880 - 1920 TDD
n40 2300 - 2400 TDD
n41 2496 - 2690 TDD
n50 1432 - 1517 TDD
n51 1427 - 1432 TDD
n66 1710 - 1780 TDD
n70 1695 - 1710 TDD
n71 663 - 698 TDD
n74 1427 - 1470 TDD
n75 -- 1432 - 1517 SDL
n76 -- 1427 - 1432 SDL
n77 3300 - 4200 TDD
n78 3300 - 3800 TDD
n79 4400 - 5000 TDD
n80 1710 - 1785 -- SUL
n81 8800 - 915 -- SUL
n82 832 - 862 -- SUL
n83 703 - 748 -- SUL
n84 1920 - 1980 -- SUL
n86 1710 - 1780 -- SUL
Table 6. Frequency Range 1
5G NR UPLINK BAND DOWNLINK DUPLEX MODE

FREQUENCY (MHZ) BAND (MHZ)
BAND
n257 26 500 - 29500 26500 - 29500 TDD
n258 24 250 - 27 500 24 250 - 27 500 TDD
n260 37 000 - 40 000 37 000 - 40 000 TDD
n261 27 500 - 28 350 27 500 - 28 350 TDD
Table 7. Frequency Range 2
The frequency bands in FR1 utilise many of the same frequency bands as those
used for 4G and other mobile communications cellular services. It is envisaged that over
time, the channels and also the bands used for carrying 5G data will take over more of the
bands already allocated to mobile or cellular telecommunications. In this way, 5G
wireless technology will be able to carry the required traffic levels.
Bands have been set aside for frequency division duplex, FDD usage, or time
division duplex, TDD usage. For FDD usage, frequency bands are required for the uplink
and downlink, and therefore two bands are allocated. For TDD usage, only a single
channel is used for the link: time slots are allocated for the uplink and downlink rather
than different frequencies. As a result, for TDD only one band is needed.

In addition to the FDD and TDD bands, other bands have been allocated to
provide supplementary uplink and downlink capacity. The bands marked SDL are for
supplementary downlinks and SUL are for supplementary uplinks.
The frequency range 2, FR2 5G bands are now starting to gain momentum with
new development to make the microwave links viable for the large scale deployment that
will be needed.
Allocations are being made in many areas of the spectrum above 20 GHz as it is
relatively lightly used at the moment.
3.17.4 CARRIER AGGREGATION :
5G NR supports carrier aggregation to enable the system to provide the required

bandwidth for the very high speed data transfers. The specification allows for up to 16
component carriers to be aggregated using various combinations of inter-band and intra-
band carrier aggregation.
The feature can be used in a smart fashion to overcome some of the issues that
may occur not only with increased bandwidth, but also to overcome the issues of
increased path loss at higher frequencies.
In terms of the allocations above it will be seen that supplementary uplinks, SUL
and supplementary downlinks, SDL can be used.
3.17.5 CHANNEL BANDWIDTH:
Figure 33: 5G Channel Bandwidth

3.17.6 5G NR PARAMETERS SUMMARY
5G NR PARAMETERS FOR DIFFERENT FREQUENCY BANDS

5G NR PARAMETER FR1 FR2
Bandwidth options per carrier 5, 10, 15, 20, 25, 30, 40, 50, 60, 50, 100, 200, 400 MHz
70, 80, 90, 100 MHz
Subcarrier spacing 15, 30, 60 kHz 60, 120, 240 kHz
Maximum number of 3300 (FFT 4096)
subcarriers
Carrier Aggregation Up to 16 carriers
Modulation schemes QPSK, 16QAM, 64QAM, 256QAM, uplink also allows π/2-BPSK
(only for DFT-s-OFDM).
Radio frame length 10ms
Subframe duration 1ms
Duplex mode FDD, TDD TDD
Multiple access scheme Downlink: CP-OFDM
Uplink: CP-OFDM; DFT-s-OFDM
MIMO scheme maximum of 2 code words mapped to maximum of 8 layers in
downlink and to a maximum of 4 in uplink.
Table 8. 5G NR PARAMETERS FOR DIFFERENT FREQUENCY
BANDS
3.18 5G RADIO TECHNOLOGIES
5G also incorporates many technologies, many of which are new, to enable the it
to provide the very high levels of performance required of it. By utilising these techniques
the 5G New radio, 5G NR will be able to significantly improve the performance,
flexibility, scalability and efficiency of current mobile networks.
3.18.1 MASSIVE MIMO WITH BEAM-STEERING:
The antenna technologies for 5G have provided significant opportunities for

enhancement of the performance over 4G. Although MIMO was used with 4G LTE, the
technology has been taken further.
MIMO systems use multiple antennas at the transmitter and receiver ends of a
wireless communication system. Multiple antennas use the spatial dimension in addition
to the time and frequency ones, without changing the bandwidth requirements of the
system.
The multiple data streams have their own weightings which include phase offsets
to each stream to enable the waveforms to interfere constructively at the receiver. This
maximises the signal strength to the user whilst also minimising the signal and hence
interference to other users.
MU-MIMO on the downlink significantly improves the capacity of the gNB

antennas. It scales with the minimum of the number of gNB antennas and the sum of the
number of user devices multiplied by the number of antennas per UE device. This means
that using 5G MU-MIMO the system can achieve capacity gains using gNB antenna
arrays and much simpler UE devices.

Figure 34: Multiple Antenna Techniques
Massive MIMO (multiple input and multiple output) antennas increases sector
throughput and capacity density using large numbers of antennas and Multi-user MIMO
(MU-MIMO). Each antenna is individually-controlled and may embed radio transceiver
components.
Figure 35: Massive MIMO
The release 15 version of the 3GPP specifications for New Radio (NR) supports
MIMO in both the uplink and downlink directions.
The uplink supports 2x2 MIMO and 4x4 MIMO, whereas the downlink supports
2x2 MIMO. 4x4 MIMO and 8x8 MIMO.
The release 15 version of the specifications also supports Multi-User MIMO in

both the uplink and downlink directions.

Beam-steering technology has also been adopted to enable the transmitter and
receiver antenna beams to be focussed towards the mobiles with which they are
communicating. Each mobile can have its own beam, using advanced antenna technology,
and this focussed the transmitted power where it is required and reduces interference
between mobiles. This gives a significant improvement in performance.
3.18.2 BEAMFORMING
Beamforming, as the name suggests, is used to direct radio waves to a target. This
is achieved by shaping the radio waves to point in a specific direction. The technique
combines the power from elements of the antenna array in such a way that signals at
particular angles experience constructive interference, while other signals pointing to
other angles experience destructive interference. This improves signal quality in the
specific direction, as well as data transfer speeds. 5G uses beamforming to improve the
signal quality it provides. Beamforming can be accomplished using phased array
antennas.
Figure 36: Beamforming Antenna
3.18.3 WAVEFORM AND MODULATION:
An early decision was taken to use a form of OFDM as the waveform for phase
one of the 5G New Radio. It has been very successfully used with 4G, the more recent
Wi-Fi standards and many other systems and came out as the optimum type of waveform
for the variety of different applications for 5G. With the additional processing power
available for 5G, various forms of optimisation can be applied.
Basic concept of OFDM, Orthogonal Frequency Division Multiplexing. The

specific version of OFDM used in 5G NR downlink is cyclic prefix OFDM, CP-OFDM
and it is the same waveform LTE has adopted for the downlink signal.

5G adopted actual modulation formats dependent upon the link and these include
QPSK, 16QAM, 64QAM, 256QAM and for the uplink when DFT-OFDM is used, π/2-
BPSK can be used. For the future, other forms of waveform may be developed, but
currently the waveform is based around OFDM.
3.18.4 MULTIPLE ACCESS
Again a variety of access schemes were discussed, but for the 5G New Radio,
OFDMA was implemented. For the downlink CP-OFDM was used and in the uplink
either CP-OFDM or DFT-OFDM could be used.
3.19 5G NEXTGEN NG CORE NETWORK
The requirements for the network for 5G will be particularly diverse. In one
instance, very high bandwidth communications are needed, and in other applications there
is a need for exceedingly low latency, and then there are also requirements for low data
rate communications for machine to machine and IoT applications.
In amongst this there will be normal voice communications, Internet surfing and
all the other applications that we have used and become accustomed to using.
As a result the 5G NextGen network will need to accommodate a huge diversity in

types of traffic and it will need to be able to accommodate each one with great efficiency
and effectiveness. Often it is thought that type suits all approach does not give the
optimum performance in any application, but this is what is needed for the 5G network.
To achieve the requirements for the 5G network a number of techniques are being
employed. These will make the 5G network considerably more scalable, flexible and
efficient.
3.19.1 SERVICE BASED ARCHITECTURE :
The 5G System Service Based architecture specifies a set of Network Functions

(NF) and a common bus which inter-connects those Network Functions. The Service
Based architecture is applicable to the control plane section of the 5G Core Network.
Each service is a function and several functions can be implemented in a physical node or
a virtual machine

Figure 37: Service Based Architecture

Software defined networking, SDN:
Using software defined networks, it is possible to run the network using software
rather than hardware. This provides significant improvements in terms of flexibility and
efficiency. SDN separates the control and data planes and allows for network programmability
Network functions virtualisation, NFV :
When using software defined networks it is possible to run the different network
function purely using software. This means that generic hardware can be reconfigured to
provide the different functions and it can be deployed as required on the network.
Standard hardware is fast and cheap, No specialized hardware is required. All

functions can be virtualised in cloud and capacity can be created on demand.
Network slicing:
As 5G will require very different types of network for the different applications, a
scheme known as network slicing has been devices. Using SDN and NFV it will be
possible to configure the type of network that an individual user will require for his
application. In this way the same hardware using different software can provide a low
latency level for one user, whilst providing voice communications for using different
software and other users may want other types of network performance and each one can
have a slice of the network with the performance needed.
Figure 38: Network slicing
Slice = A logical network serving a particular application, business partner, or customer.

It is similar to Virtual Machines (VMs) on a computer. A network can be divided

in too many slices. Each slice looks to the user as a separate network with reserved
resources .
Edge computing
Edge computing is delivered by computing servers closer to the ultimate user. It
reduces latency and data traffic congestion.
3.20 5G DEPLOYMENT OPTIONS
With an already deployed 4G RAN/EPC in the field and a new 5G RAN/NG-Core
deployment underway, we can‘t ignore the issue of transitioning from 4G to 5G (an issue
the IP-world has been grappling with for 20 years). 3GPP officially spells out multiple
deployment options, which can be summarized as follows.
 Standalone 4G / Stand-Alone 5G
 Non-Standalone (4G+5G RAN) over 4G‘s EPC
 Non-Standalone (4G+5G RAN) over 5G‘s NG-Core
The second of the three options, which is generally referred to as ―NSA―, involves
5G base stations being deployed alongside the existing 4G base stations in a given
geography to provide a data-rate and capacity boost. In NSA, control plane traffic
between the user equipment and the 4G Mobile Core utilizes (i.e., is forwarded through)
4G base stations, and the 5G base stations are used only to carry user traffic. Eventually,
it is expected that operators complete their migration to 5G by deploying NG Core and
connecting their 5G base stations to it for Standalone (SA) operation. NSA and SA
operations are illustrated in Figure
Figure 39: SA and Non SA Deployment

Figure 40: 5G Deployment Options
3.21 CONCLUSION
5G is going to future technology as it has low latency and high efficiency.

E3-E4 Consumer Mobility Varoius Phases of BSNL CMTS Tenders
4 VARIOUS PHASES OF BSNL CMTS TENDER

 Various phases of BSNL CMTS Tenders
4.2 INTRODUCTION
In this chapter we will have details of various phases of CMTS tender by BSNL in
North, South, East and West zones since BSNL started its mobile services and highlights
of current CTMS tender. Network capacity phase wise vendor wise in various phases of
GSM projects in BSNL(in lakhs). For CMTS , tenders are done by BSNL CO New Delhi
on zonal basis (North, East, West, South)
Sl.No Name of Circle Sl.No Name of Circle
East Zone West Zone
1. ANDMAN & NIKOBAR 1 CHHATTISGARH
2. ASSAM 2 GUJARAT
3. BIHAR 3 MADHYA PRADESH
4. JHARKHAND 4 MAHARASHTRA
5. NORTH EAST-I
6. NORTH EAST-II
7. ORISSA
8. WEST BENGAL
9. KOLKATA TD
North Zone South Zone
1. HARAYNA 1 ANDHRA PRADESH
2. HIMACHAL PRADESH 2 TELANGANA
3. JAMMU & KASHMIR 3 KARNATAKA
4. PUNJAB 4 KERALA
5. RAJASTHAN 5 TAMILNADU
6. UTTAR PRADESH (E) 6 CHENNAI PHONES
7. UTTAR PRADESH (W)
8. UTTARAKHAND
Table 9. Various Zone and States
4.3 BSNL TENDER DIFFERENT PHASES
4.3.1 PHASE –I
This was the first tender of the BSNL CMTS , the tender was intended to procure
GSM lines. The supply in North and East zone was made by M/s Ericsson, in south by
M/s Motorola and in west by M/s Lucent through ITI. The supply was of 2G –GSM
equipment only.
4.3.2 PHASE –II AND II+
This was the second tender of the BSNL CMTS , the tender was intended to add-
the capacity of GSM/GPRS lines. The supply in North and East zone was made by M/s
Ericsson, in south by M/s Motorola and in west by M/s Lucent through ITI. The supply
was of 2G –GSM/GPRS equipment. The bidder were same as in phase-I
4.3.3 PHASE –III AND III+
This was the add-on of second tender of the BSNL CMTS , the tender was
intended to supply the extra capacity of GSM/GPRS lines. The supply in North and East

zone was made by M/s Ericsson, in south by M/s Motorola, West zone has not got any
supply in this phase. The supply was of 2G –GSM/GPRS equipment. The bidder were
same as in phase-I/II except in west zone
4.3.4 PHASE –IV ,IV+, IV++, IV+++
This was the new tender of the BSNL CMTS in 2004, the tender was intended to
supply the extra capacity of GSM/GPRS lines. The supply in South and East zone was
made by M/s Nortel, in North by M/s Nokia, West zone has not got any supply in this
phase. The supply was of 2G –GSM/GPRS equipment. In phase IV+, IV++ and IV +++
Ercisson and Motorola were the suppliers.
4.3.5 PHASE –V, V.1 AND V.2, V.2
This was the new tender of the BSNL CMTS in 2006, the tender was intended to supply
the IMPCS 2G/3G COMBO network. Phase-V.1-17.5 million, Phase-V.2 - 14 million,
Phase-V.3 - 14 million Total 45.5 million lines. The supply in North and East zone was
made by M/s Ericson, in South by M/s Huawei, West zone has supply from M/s Alcatel
in this phase. The supply was of 2G –GSM/GPRS equipment. In phase IV+, IV++ and IV
+++ Ericsson and Motorola were the suppliers. The details is as follows
Table 10. Details of Component for Phase V supply

Phase V.2 was for USO site supply for
4.3.6 PHASE VII, VII+
This was the new tender of the BSNL CMTS in 2011-12, the tender was intended
to supply the 2G/3G COMBO network. In Phase-VII the supplier was ZTE on pan India
Basis Circles were authorized to is Purchase Order (PO) by BSNLCO New Delhi as per
APO issued by Corporate office. The total supply was of 150 Lakhs ( 15 million) lines.
4.3.7 PHASE VIII.4
This was the new tender of the BSNL CMTS in 2015-16, the tender was intended
to supply the 2G/3G COMBO network along with upgradation and supply of 4G
equipment. In Phase-VII.4I the supplier was ZTE in North and East , Nokia in South and
West. Basis Circles were authorized to is Purchase Order (PO) by BSNLCO New Delhi
as per APO issued by Corporate office. The supplies detail is as follows
Vendor Capacity Vendor Capacity Vendor Capacity Vendor Capacity

2G-
2G-21.32 2G-41.81 2G-71.51
ZTE 55.453G- ZTE Nokia
3G-35.80 3G-55.49 Nokia WEST 3G-88.60
NORTH 71.854G- EAST SOUTH
4G-16.22 4G-30.16 4G-26.90
13.09
Table 11. Vendor and Capacity in Phase VIII.4

4.3.8 PHASE IX
Phase IX project for deployment of 4G network in BSNL, the tender is in the
planning phase. The tender is mainly for setting and upgrading to 4G Network.
4.4 VARIOUS BSNL CMTS TENDERS
The details of various phases of CMTS tender by BSNL in North, South, East and
West zones since BSNL started its mobile services and highlights of current CTMS
tender are given in table. Network capacity phase wise vendor wise in various phases of
GSM projects in BSNL(in lakhs)
Total
Sl Phase/
North East South West Phase
No. Zone
wise
Capa Capa Capa Capa
Vendor Vendor Vendor Vendor
city city city city
1 Ph I Ericsson 4.20 Ericsson 1.51 Motorola 5.78 ITI/Lucent 4.08 15.57
PH II
2 Ericsson 6.38 Ericsson 3.30 Motorola 8.03 ITI/Lucent 6.82 24.53
& II+
3 PH II+ Ericsson 2.71 Ericsson 1.17 Motorola 3.46 - 0.00 7.34
Pilot
project
4 0.00 Ericsson 0.41 0.00 0.00 0.41
redeplo
yment
10.9
5 PH III Ericsson 6.81 Ericsson 3.13 Motorola - 0.00 20.87
3
PH
6 Ericsson 4.55 Ericsson 3.78 Motorola 2.35 - 0.00 10.68
III+
7 PH IV Nokia 42.0 Nortel 30.0 Nortel 40.0 ITI/Alcatel 40.0 152.00
PH
8 Ericsson 8.70 Ericsson 6.23 Motorola 5.06 - 0.00 19.99
IV+
PH Nokia 20.0 Nortel 2.60
9 - 0.00 ITI/Alcatel 20.0 48.60
IV++ Ericsson 6.00 - 0.00
PH 17.4
10 Ericsson 7.63 Ericsson - - - - 25.04
IV+++ 1
27.0
Phase - - - - Nortel - -
11 5 50.05
IV.5
- - - - Motorola 23 - -
Phase 90.0
12 Ericsson 50 Ericsson 55 ITI/Huawei 90 ITI/Alcatel 285.00
V.1 0
Phase
31.9
13 V.2/U Ericsson Ericsson 5.29 - - - - 37.26
7
SO
Phase 42.1 40.1
14 ZTE 61.4 ZTE ZTE ZTE 6.29 150.00
VII 9 2
Phase 31.6 33.2
15 ZTE 15 ZTE ZTE 79.94
VII + 9 5
Ph
16 ZTE ZTE Nokia Nokia
VIII.4
Table 12. Various Phases of BSNL CMTS Tender

Table 13. Phase VIII.4 Tentative Node Schedule

4.5 CONCLUSION
Various phases of BSNL CMTS Tenders have been discussed.

E3-E4 Consumer Mobility Backhaul Media for Mobile Radio Network
5 BACKHAUL MEDIA FOR MOBILE RADIO NETWORK

(OFC/ OFC SYSTEMS/ MINI LINK) AND RRH
 Importance of backhaul media in 3G
 Various type of Backhaul media
 Choice of backhauling
 Concept of Cloud RAN
5.2 INTRODUCTION
The physical part of a communications network between the central backbone and
the individual local networks is known as backhaul. Mobile backhaul refers to the
transport network that connects the core network and the RAN (Radio Access Network)
of the mobile network. Recently, the introduction of small cells has given rise to the
concept of front haul, which is a transport network that connects the macro cell to the
small cells. Whilst mobile backhaul and front haul are different concept, the term mobile
backhaul is generally used to encompass both concepts.
Figure 41: Backhaul Concept

Cell phones communicating with a single cell tower constitute a local subnetwork;
the connection between the cell tower and the rest of the world begins with a backhaul
link to the core of the internet service provider's network (via a point of presence). A
backhaul may include wired, fiber optic and wireless components. Wireless sections may
include using microwave bands and mesh and edge network topologies that may use a
high-capacity wireless channel to get packets to the microwave or fiber links.
5.3 MOBILE BACKHAUL N/W
 Mobile backhaul is the transport network that connects the core network
and the RAN/Cell Site.
 The connection between the cell tower and the rest of the world begins
with a backhaul link to the core N/w.

 A backhaul may include wired, fiber optic and wireless components.
 Wireless sections may include using microwave bands and mesh and edge
network topologies
 Interconnection b/n core network elements is done through backbone N/w.
5.3.1 FRONT HAUL VS BACKHAUL
 Split RAN architecture has reshaped the traditional definitions of front

haul and backhaul.
 In its earliest incarnation, backhaul was simply described as the connection

between Cell Site to BSC/RNC (In 2G/3G)
 Front haul became a necessary addition when a new link connected

centralized BBU to individual RRH.
 Front haul is connection in RAN infrastructure between the Baseband Unit

(BBU) and Remote Radio Head (RRH).
 Front haul originated with LTE networks when operators first moved their
radios closer to the antennas.
 This new link was established to supplement to the backhaul connection

between the BBU and central network core.
5.4 IMPORTANCE OF MOBILE BACKHAUL
Wireless and fixed-line backhaul infrastructure is an essential component of the
mobile telecommunications network. Mobile networks are ubiquitous and support a mix
of voice, video, text and data traffic originating from and terminating to mobile devices.
All of this traffic must be conveyed between the mobile cellular base stations and the core
network. The 3G and 4G Long-Term Evolution (LTE) strive for more network capacity,
latency reduction, and the need to deliver an enhanced user experience. In the era of 5G,
where a network will be densified and more stringent requirement will be imposed,
mobile backhaul will become even more important.
5.5 MOBILE BACKBONE NETWORK
Mobile backbone network refers to the interconnection of core elements situated
at separate geographic locations. As the requirement of bandwidth is large, typically,
OFC is used in the backbone network. However, MW is also sometimes used in the
backbone network, particularly in those areas where laying fibre is not a feasible option
due to difficult terrain, time constraints or economic viability.
5.6 TECHNOLOGY CHOICES FOR MOBILE BACKHAUL

The most common network type in which backhaul is implemented is a mobile
network. A backhaul of a mobile network, also referred to as mobile-backhaul connects a
cell site towards the core network. The two main methods of mobile backhaul
implementations are fiber-based backhaul and wireless point-to-point backhaul. Other
methods, such as copper-based wire line, satellite communications and point-to-

multipoint wireless technologies are being phased out as capacity and latency
requirements become higher in 4G and 5G networks.
Figure 42: Mobile Backhaul Network Choices

The technological solutions used for backhaul, including both wireline and
wireless solutions are given below:
5.6.1 COPPER-LINE
Copper-based backhaul was the primary backhaul technology for 2G/3G. At the
heart of copper-based backhaul is the T1/E1 protocol, which supported 1.5 Mbps to 2
Mbps. This bandwidth can be boosted by using DSL over the copper pair and DSL is still
an option for mobile backhaul for indoor small cells, in-building and public venue small
cell networks.
5.6.2 FIBRE-OPTIC IN BACKHAUL MEDIA FOR MOBILE RADIO

NETWORK (OFC/OFC SYSTEMS)
This technology is the mainstay wired backhaul in MNO networks and second
overall only to microwave backhaul. Even though fibre has significant inherent
bandwidth carrying capability, several additional techniques can be used to offset any
bandwidth constraints and essentially rendering the fibre assets future-proof.

Figure 43: OFC Media and System Mobile Network Backhaul

These techniques include Wavelength Division Multiplexing (WDM) technology
which enables multiple optical signals to be conveyed in parallel by carrying each signal
on a different wavelength or colour of light. WDM can be divided into Coarse WDM
(CDWM) or Dense WDM (DWDM). CWDM provides 8 channels using 8 wavelengths,
while DWDM uses close channel spacing to deliver even more throughput per fibre.
Modern systems can handle up to 160 signals, each with a bandwidth of 10 Gbps for a
total theoretical capacity of 1.6 Tbps per fibre.
The traffic generated by LTE has accelerated the demand for Fiber to the Tower
(FTTT) and has required Mobile Network Operators (MNOs) to upgrade many aspects of
their backhaul networks to fibre-based Carrier Ethernet. The main limitations of fibre are
the cost and logistics of deploying fibre (ducts etc.). Also it can take several months to
provision a cell site with fibre optic backhaul. Fibre optic will remain as the main choice
for backhaul.
5.6.3 WIRELESS BACKHAUL (MICROWAVE MINI-LINK)
Despite fibre being the preferred choice for 3G/4G/5G backhaul, microwave
backhaul is the most used technology due to a combination of its capability and relative
ease of deployment (i.e. no need for trenches/ducting) making it a low-cost option that
can be deployed in a matter of days. Microwave backhaul solutions in the 7 GHz to 40
GHz bands, in addition to higher microwave bands such as V-band (60 GHz) and the E-
band (70/80 GHz) can be relied. Backhaul links using the V-band or the E-band are well
suited to supporting 5G due to their 10 Gbps to 25 Gbps data throughput capabilities.

Figure 44: Microwave Mini-Links for Mobile Communications

Microwave can be used in LOS or NLOS mode which makes it ideal to be used in
a chain, mesh or ring topologies to enable resilience and/or reach.
5.6.4 LOS VS. NLOS
LOS backhaul has the advantage of using a highly directed beam with little fading
or multi-path dispersion and enables efficient use of spectrum as multiple transceivers can
be located within a few feet of each other and use the same frequency to transmit different
data streams.
NLOS backhaul is much more ―plug and play‖ and so take less time with less
skilled labour to set up. NLOS backhaul OFDM technology (Orthogonal Frequency
Division Multiplexing) to relay information back to a central base station. NLOS
backhaul needs only to be within a range of the receiver unit with OFDM providing a
level of tolerance to multi-path fading not possible with LOS
5.6.5 SATELLITE BACKHAUL
Satellite Backhaul is a niche solution and used in fringe areas (e.g. remote rural
areas) and sometimes as an emergency/temporary measure (e.g. a disaster area. This
backhaul is used in developing markets and as a complementary role in developed
markets. The technology can deliver 150Mbps/10Mbps (downlink/.uplink). However,
latency is a challenge as there a round trip delay of circa 500-600ms for a geostationary
satellite. LEO (Low Earth Orbit) satellites have tried to address the latency issue (i.e.
using a much lower orbit of 1500km versus 36000km and resulting in a one way trip of
circa 50ms). However, LEO satellites are not geostationary and thus there is sometimes a
need to route traffic via multiple satellites.
5.6.6 FREE SPACE OPTICS (FSO)
Free Space Optics (FSO) is a newer low-latency technology that offers speeds
comparable to fibre optics that transmit voice, video and data with up to 1.5Gbps, and can
be deployed as backhaul to expand mobile network footprint with building-to-building
connectivity. The high bandwidth can be provided with a reception of light by deploying
free space optics technology.

BSNL is likely to use free space optics, a new line-of-sight outdoor wireless
technology, to overcome backhaul constraints in large arid areas of Rajasthan and Gujarat
plains.
5.6.7 WIFI BACKHAUL
There is marginal use of this technology for macrocell backhaul. The unlicensed
nature of the technology combined with the growing interference from increasing public
and private WLANs plus poor transmission ranges severely limits its deployment.
5.7 CHALLENGES IN MOBILE BACKHAUL
There are a number of market trends that result in new challenges and
requirements that must be met by the backhaul.
5.7.1 EVOLUTION OF LTE
Technical innovations occurring on LTE, which is known as LTE-Advanced Pro

or 4.5G which enable enhancements such as improved peak bandwidth and greater energy
efficiency for IoT connections. The peak bandwidth of 4.5G is around 1Gbps which is 8-
10x higher than standard LTE, and will enable (inter alia) support of video traffic at 4K
resolution to mobile devices.
5.7.2 EMERGENCE OF 5G
The 5G network will comprise both NR (New Radio) as well as a new 5G

Core Network (5GC). The advent of NR offers a leap in bandwidth speeds in comparison
to 3G and 4G via the utilisation of higher frequency spectrum. The higher frequencies
enable wider channel bandwidths at the access but also result in smaller cell sizes. Both
have implications for backhaul.
5.7.3 NETWORK SLICING
In 5G Network, one concept of ―network slicing‖ is introduced whereby the

physical network infrastructure can be partitioned into bespoke logical networks
(―slices‖) in the RAN and 5G core which are targeted to the needs of a specific
application or use case. Slicing will impact on the backhaul network.
5.7.4 SUBSCRIBER GROWTH
Backhaul strategy/evolution must cope with both an increase in subscriptions as

well as a large number of those subscriptions being ―high bandwidth‖ users.
5.7.5 MOBILE DATA TRAFFIC GROWTH
The increasing subscriber total plus increased access bandwidth usage of those
subscribers results in mobile data traffic increasing at a rate.
5.7.6 STRINGENT LATENCY REQUIREMENTS
Both 5G mission-critical applications and increased video streaming will result in

more stringent end-end latency requirements and impact on the backhaul latency budget.

If higher latency backhaul links are deployed (e.g. satellite links), then such backhaul
would only carry 2G/3G and non-latency sensitive LTE services.
5.7.7 NETWORK DENSIFICATION:
The increased demand for mobile broadband results in the number of macrocell.
The new macrocells include both 4G and 5G technologies. This results in extra traffic to
backhaul as well as additional challenges due to the smaller cell size for 5G NR.
5.8 ALTERNATIVE ARCHITECTURES FOR MOBILE
BACKHAUL OPTIMISATION
5.8.1 MULTI ACCESS EDGE COMPUTING
MEC (Multi-access edge computing) is where computing and intelligence

capabilities that were mostly centralized in the core network are provided at the edge of
the access network. MEC enables high bandwidth and ultra-low latency access to cloud
computing/IT services at the edge to be accessed by applications developers and content
providers.
MEC, while incurring a cost to implement core functions at the edge, can provide
opportunities to optimise backhaul demand via caching and/or local breakout. Caching
reduces the load on mobile backhaul and enhances the customer experience by storing
frequently accessed contents in the edge network. Customers can access the contents at a
lower latency (with less distance for signal to travel) and backhaul demand is reduced as
there is no need to reach further to the external network to obtain the contents. Local
breakout also enables the mobile backhaul to be optimised as the contents do not need to
travel to the core network and then to the internet. The caveat with local breakout is that
the transport network to connect the edge to the internet needs to be in place and therefore
won‘t optimise cost in certain scenarios.
5.8.2 CLOUD RAN
Cloud RAN is where some layers of radio access network are centralized to an
edge site rather than at the cell site, which allows some (or all) of the processing
capabilities to be focused at the edge site reducing the complexities at the cell site. This
architecture is suitable in the small cell era, where only a little space and cost constraint is
affordable at the cell site. While the architecture may not be suitable for traditional
macrocell base stations as they would need to process significant load of signal
transmitted from/received by various radio elements, heterogeneous networks with many
small cells would benefit from this architecture.
As shown in the figure below, Cloud RAN in its two forms (low-level and high-
level splits) significantly reduces complexities and capabilities at the cell site to be
concentrated in the edge site. The low-level split is where only the physical layer is
processed at the edge site while all the electronics are concentrated in the edge site. This
architecture allows easy installation and very low complexity at the cell site but comes at
a higher fronthaul cost as baseband signals would need to be transferred. On the other
hand, high-level split brings relatively less fronthaul cost but comes with more
complexity at the cell site than low-level split.

Figure 45: Cloud RAN Architecture

5.8.3 MOBILE BACKBONE NETWORK
Mobile backbone network refers to the interconnection of core elements situated
at separate geographic locations. As the requirement of bandwidth is large, typically,
OFC is used in the backbone network. However, MW is also sometimes used in the
backbone network, particularly in those areas where laying fibre is not a feasible option
due to difficult terrain, time constraints or economic viability.
5.8.4 TYPES OF MW RF CARRIERS
For PtP links, MW frequencies are generally assigned in chunks of 2x28 MHz,
known as MW carriers. There are two types of MW carrier viz. Microwave Access
(MWA) carriers and Microwave Backbone (MWB) carriers.
MWA carriers refer to the MW carriers in the frequency bands of 10 GHz and
beyond. These are assigned for short-haul systems which are used to carry traffic through
relatively shorter distances. MWA carriers are typically used in the mobile backhaul
networks (mainly in the pre-aggregation part). In India, currently 13 GHz (12.750-13.250
GHz), 15 GHz (14.5-15.5 GHz), 18 GHz (17.7-19.7 GHz) and 21 GHz (21.2-23.6 GHz)
bands are used for the assignment of frequencies for MWA carriers.
Band (GHz) 13 15 18 21
No. of carriers (2x28 MHz) 8 15 32 40
MWB carriers are assigned for relatively longer links. These are assigned for a
minimum link length of 15 Km. However, in the hilly terrains (including Assam, North-
East, Himachal Pradesh and Jammu and Kashmir LSAs), MWB carriers are assigned for
a minimum link length of 10 Km4. Normally carriers in the frequency bands below 10
GHz are assigned for MWB carriers. In India, currently 6 GHz (5.925-6.425 GHz) and 7
GHz (7.425-7.725 GHz) bands are used for the assignment of frequencies for MWB
carriers. MWB carriers are generally used in the backbone networks of the cellular
network. These can also be used in backhaul section if the distance of link length is more.
Global Microwave Bands

The frequency bands available for microwave backhaulare defined by ITU-R

Radio Regulations 2008 with a globalregion dependency. Below Table summarizes the
global bands (subject to regional variations), together with typical maximum link lengths.
Table 14. MW RF Carriers Frequency bands

Backhaul Requirement for different Access Technologies
Table 15. Backhaul Capacity

5.8.5 RRH
A remote radio head (RRH), also called a remote radio unit (RRU) in wireless
networks, is a remote radio transceiver that connects to radio base station unit via
electrical or wireless interface.
The RRH is termed ―Remote‖ as it is usually installed on a mast-top, or tower-top

location that is physically some distance away from the base station hardware which is
often mounted in an indoor rack-mounted location. In wireless system technologies such

as GSM, CDMA, UMTS, LTE this Radio equipment is remote to the

BTS/NodeB/eNodeB, and is also called Remote Radio Head.
This equipment will be used to extend the coverage of a BTS/NodeB/eNodeB like

rural areas or tunnels. They are generally connected to the BTS/NodeB/eNodeB via a
fibre optic cable using Common Public Radio Interface protocols.
Figure 46: RRH

Using Wireless (Microwave, Millimetre Wave, MMW, Free Space Optics, and
FSO) links instead of fibre allows the Remote Radio Head (RRH) to be connected
without need for fibre optics. By avoiding the needs for digging, trenches, leased circuits
from telcos, dark fibre or way-leaves for disrupting busy city streets, 4G/LTE networks
can be realised very quickly with installation taking hours rather than days, weeks or
months.
Figure 47: Backhaul for RRH

5.8.6 IMPORTANCE OF RRH
RRHs have become one of the most important subsystems of today's new
distributed base stations. The RRH contains the base station's RF circuitry plus analog-to-
digital/digital-to-analog converters and up/down converters. RRHs also have operation

and management processing capabilities and a standardized optical interface to connect to

the rest of the base station. This will be increasingly true as LTE and WiMAX are
deployed. Remote radio heads make MIMO operation easier; they increase a base
station's efficiency and facilitate easier physical location for gap coverage problems.
RRHs will use the latest RF component technology including Gallium nitride (GaN) RF
power devices and envelope tracking technology within the RRH RF power amplifier
(RFPA).
5.8.7 RRH PROTECTION IN FIBER TO THE ANTENNA SYSTEMS
Fourth generation (4G) and beyond infrastructure deployments will include the
implementation of Fiber to the Antenna (FTTA) architecture. FTTA architecture has
enabled lower power requirements, distributed antenna sites, and a reduced base station
footprint than conventional tower sites. The use of FTTA will promote the separation of
power and signal components from the base station and their relocation to the top of the
tower mast in a Remote Radio Head (RRH).
According to the Telcordia industry standard that establishes generic requirements

for Fiber to the Antenna (FTTA) protection GR-3177,the RRH shifts the entire high-
frequency and power electronic segments from the base station to a location adjacent to
the antenna. The RRH will be served by optical fiber and DC power for the optical-to-
electronic conversion at the RRH.
RRHs located on cell towers will require Surge Protective Devices (SPDs) to
protect the system from lightning strikes and induced power surges. There is also a
change in electrical overstress exposure due to the relocation of the equipment from the
base station to the top of the mast.
5.8.8 PROTECTION FROM LIGHTNING DAMAGE
RRHs can be installed in a low-profile arrangement along a rooftop, or can

involve a much higher tower arrangement. When installed at the highest point on a
structure (whether a building or a dedicated cell tower), they will be more vulnerable to
receiving a direct lightning strike and higher induced lightning levels, compared with
those installed in a lower profile manner below the upper edges of the building.
As noted in GR-3177, while surges can be induced into the RRH wiring for
lightning striking the nearby rooftop or even the base station closure, the worst case will
occur when a direct strike occurs to the antenna or its supporting structure. Designing the
electrical protection to handle this situation will provide protection for less damaging
scenarios... it can also be use in optical fiber communication but different type.
5.9 CONCLUSION
In order to have best of Network and throughput from it backhaul is of at most
importance. Introduction of cloud RAN has open the path for low latency network and
path for future radio technologies.

E3-E4 Consumer Mobility KPI Reports for 2G/3G/4G
6 KPI REPORTS FOR 2G/3G/4G

After completion of this chapter participant will able to understand:
 KPIs of 2G Network
 Impact of KPIs and Network Performance.
 KPI Threshold Values.
6.2 INTRODUCTION
Telecom Service Providers use Key Performance Indicators (KPIs) to judge their
network performance and evaluate the Quality of Service (QoS). Regulatory authority
also uses KPIs to monitor Quality of Service of different operator. The KPIs are actually
the statistical measure of network quality and encompass all the QoS parameters related
to Network Accessibility, Service Accessibility, and Network Retainability
Key Performance Indicators are a set of quantifiable measures used in GSM,

UMTS, HSPA, and LTE networks to gauge or compare performance in terms of meeting
mobile network‘s strategic and operational goals. KPIs vary between management,
marketing, operations and network engineering people depending on their priorities,
perspectives or performance criteria sometimes referred to as ―key success indicators
(KSI)‖.
6.3 KPI OF GSM
In GSM all the events being occurred over air interface are triggering different
counters in the Base Station Controller (BSC). The KPIs are derived with the help of
these counters using different formulations. RF Optimizer makes frequent use of
statistical data for routine optimization activities. This raw data, which is actually based
on counters, makes optimization tasks quite cumbersome as counters are in thousands.
So, to make the tasks simpler, counters are appended into formulae, whereas, each
formula reflects a specific performance indicator. All major performance indicators are
categorized as Key Performance Indicators (KPIs). The KPIs are available in report form
through OMC.
Following 2G network KPI optimizations are covered in this chapter:
 SDCCH congestion Rate
 SDCCH drop Rate
 TCH congestion/Blocking Rate
 Call Setup Success Rate
 TCH (call) drop Rate
 Handover Success Rate
 Paging Success Rate
 RACH Success Rate
 Data KPI improvement
6.3.1 SDCCH CONGESTION RATE
During Location Update and set up of MO and MT calls, MS usually seizes SDCCH
to exchange signalling. SMS is also sent/delivered through SDCCH channel in idle mode.

When BSC receives SDCCH request from MS, it checks SDCCH resource. If all
SDCCHs are occupied at that moment, SDCCH congestion takes place. Its day average
value should be ≤ 1%.
Causes and solutions:
(a) Large traffic volume exceeding network capacity
Solution: Increase cell capacity by adding more TRXs.
(b) Too many location update at LAC boundaries
Solution: (i) Adjust LAC selection and/or modify LAC boundaries
(ii) Adjust CRH (Cell Reselection Hysteresis)
(iii) Adjust parameter setting of periodic location update timer (T3212)
(c) Too much SMS traffic
Solution: (i) Implement dynamic SDCCH allocation mode
(ii) Increase SDCCH channels
(d) Hardware fault in TRX or transmission system (Abis link etc.)
Solution: (i) Replace the faulty hardware
(ii) Check and repair the transmission system
(e) Unreasonable setting of system parameters and RACH parameters
Solution:
(i) Increase RACH access threshold appropriately to cope with interference
(ii) Reduce Max Retrans appropriately
6.3.2 SDCCH DROP RATE:

When MS is already on SDCCH and in-between communication with Base station
SDCCH channel got disconnected abruptly then SDCCH Drop has occurred.
Process for Optimization:
Identify the Bad performing Cells for SDCCH Drop Rate. Then follow the below
mentioned Process after Analyzing detailed report
a) The Main Reasons for High SDCCH Drop Rate are improper Parameters
Configuration and Bad RF & Environmental factors.
b) First Audit for any parameters related discrepancies and define as per standard
parameters set.
c) Check for Neighbour Relations and correct if it is not proper.
d) Low Coverage: Through Drive Test Find out the low coverage patched and try to
improve the coverage.
e) Interference: Check for interference from repeaters, Intra-Network interference
due to aggressive reuse or improper Freq., Inter-Network can also be the case.
Find out the actual cause and rectify it.
f) Antenna System: High VSWR due to feeders, improper antenna configuration
(Ex. Sector cable Swap)
g) Check for Hardware Issue and rectify if you found any.
h) After the activity check the subsequent days report and repeat the procedure for
pin pointing the actual cause.
6.4 TCH CONGESTION/BLOCKING RATE
If during call attempt MS is not getting a TCH as all the available TCH in the cell
are already occupied, TCH congestion/blocking occurs. Its day average value should be ≤
2%.
Process for Optimization:

 Check TRX/Hardware Fault in the affected cell

 Check carried Traffic (Erlang) from BH Report and increase no. of TRX in
the cell (If possible). No. of TCH required according to traffic can be
analyzed from Erlang-B table (please see the table)
 Implement Half Rate/AMR-Half Rate if already maximum no. of TRX is
equipped.
Explore possibilities of sharing the traffic of affected cell with neighbouring cell
by:
 Antenna azimuth/tilt/height adjustment of affected/ neighbouring cells.
 HO margin adjustment for making logical slope to neighbouring cells.
 Directed Retry/Traffic handover may be enabled.
 In very exceptional cases power of affected cell may be reduced.
 Additional sector may be installed in the affected BTS.
 Dual band may be implemented in the affected BTS to increase no. of
TRX.
 Last option: Introduction of new BTS in the affected area
Table 16. Erlang B Table

6.4.1 CALL SETUP SUCCESS RATE (CSSR)
CSSR indicates the probability of successful calls initiated by MS. It is an
important KPI for evaluating the network performance. If CSSR is too low, the
subscribers are not likely to make calls successfully. Its value should be ≥95%
CSSR value depends on

I. SDCCH Assignment success Rate

II. SDCCH Drop Rate
III. TCH Assignment Success Rate
Process of optimisation
Find out the causes of a low CSSR.(Check whether a low CSSR is caused by
SDCCH/Immediate Assignment Success Rate problems, SDCCH Drop Rate problems, or
TCH Assignment Success Rate problems.) and accordingly following actions may be
taken
a) Minimise SDCCH Congestion (Refer SDCCH Congestion in the same chapter)
b) Minimise SCDDH Drop (Refer SDCCH Drop in the same chapter)
c) Minimise TCH Congestion (Refer TCH Congestion in the same chapter)
d) Check Hardware/Transmission Faults and Feeder Cable Swap (if any)
e) Check value of parameters like RXLEV_ACCESS_MIN/RACH Min Access
Level/Tx-integer etc.
6.4.2 CALL DROP RATE
Call drops are identified through SACCH messages. A Radio Link Failure counter
(RLT) value is broadcast on the BCH. The counter value may vary from network to
network. At the establishment of a dedicated channel, the counter is set to the broadcast
value (which will be the maximum allowable for the connection). The mobile decrements
the counter by 1 for every FER (unrecoverable block of data) detected on the SACCH and
increases the counter by 2 for every data block that is correctly received (up to the initial
maximum
value). If this counter reaches zero, a radio link failure is declared by the mobile and it
returns back to the idle mode.
If the counter reaches zero when the mobile is on a SDCCH then it is an SDCCH Drop. If
it happens on a TCH, it is a TCH drop.
Sometimes an attempted handover, which may in itself have been an attempt to
prevent a drop, can result in a dropped call.
When the quality drops, a mobile is usually commanded to perform a handover.
Sometimes however, when it attempts to handover, it finds that the target cell is not
suitable. When this happens it jumps back to the old cell and sends a Handover Failure
message to the old cell. At this stage, if the handover was attempted at the survival
threshold, the call may get dropped anyway. If on the other hand the thresholds were
somewhat higher, the network can attempt another handover. Call Drop Rate should be ≤
2%.
Causes of call drop
a) Blind spot, low coverage level.
b) Unavoidable interference can be the inter network interference, interference from
repeaters, or intra network interference resulting from aggressive frequency reuse.
c) Poor transmission quality and unstable transmission links over the Abis interface end
other interfaces.
d) Faulty hardware/high VSWR/ Feeder Cable swap
e) Unreasonable settings of handover parameters/during inter BSC/MSC handover.
f) If pre-emption is used in MSC then lower priority MS will face call drop.
g) Unreasonable setting of radio parameters.
a) Check radio parameters. Adjust unreasonable settings of radio parameters.
b) Proper frequency plan viz. achieve minimum interference level by proper BCCH
planning, HSN, MAIO planning.

c) Minimizing coverage holes by physical optimization (Orientation, Height, E.Tilt,

M.Tilt).
d) Setting Radio link timeout parameter as per inter site distance viz. for rural sites RLT
can be of higher value.
e) Similar for Rural site where uplink quality is poor, Rxlev Access min, Rach Access
min parameter can be set appropriately. Proper balance should be maintained for this
parameter else path imbalance will result and TCH drop will increase.
f) Minimize Abis and other interface fluctuation – Link stability plays very vital role.
g) Check and remove BTS/BSC hardware fault and Cable swap/high VSWR (if any).
h) During HO to neighbour cells should be having free TCH resources else call drop may
increase. For this proper half rate thresholds should be defined as per traffic pattern,
decongestion of these cells by capacity argument.
i) Proper Neighbour definition should be maintained – some handovers cannot be
performed and thus call drops.
6.4.3 HANDOVER SUCCESS RATE (HOSR)
Handovers are meant for maintaining call continuity when subscriber crosses over from
one cell to another cell. KPI to be monitored for handover performance in GSM is
―Handover Success Rate‖.
Handover Process: The overall handover process is implemented in the MS, BSS &
MSC.
 Measurement of radio subsystem downlink performance and signal strengths received
from surrounding cells, is made in the MS.
 These measurements are sent to the BSS for assessment.
 The BSS measures the uplink performance for the MS being served and also assesses
the signal strength of interference on its idle traffic channels.
 Initial assessment of the measurements in conjunction with defined thresholds and
handover strategy may be performed in the BSS. Assessment requiring measurement
results from other BSS or other information resident in the MSC, may be perform. In
the MSC.
 The MS assists the handover decision process by performing certain measurements.
 When the MS is engaged in a speech conversation, a portion of the TDMA frame is
idle while the rest of the frame is used for uplink (BTS receive) and downlink (BTS
transmit) timeslots.
 During the idle time period of the frame, the MS changes radio channel frequency and
monitors and measures the signal level of the six best neighbour cells.
 Measurements which feed the handover decision algorithm are made at both ends of
the radio link.
a) Identify the Bad performing Cells for HOSR
b) Take the detailed report showing cause & target cell
c) Check whether HO parameters are defined correctly.
d) BCCH & BSIC confusion i.e. check whether same BCCH and BSIC combination
is repeated in nearby cells.
e) Minimise TCH Congestion as TCH congestion in target cell results HO fail.
f) Unnecessary Handovers – more number of handovers, higher risk of facing
quality problem and even in call drop
g) Missing neighbour – Best server is not in there in neighbour list
h) Feeder cable swap
i) One way neighbour handover

j) If neighbour is defined through external cells (between cells in different OMC

servers e.g. 2G-3G HO/HO b/w cells of different vendors) - need to define correct
CGI, BCCH, BSIC etc. in external cells.
6.4.4 PAGING SUCCESS RATE
Paging Success rate is the percentage of valid page responses received by the system.
Paging Channel Congestion should be ≤ 1%.
a) Removal of non existing Cell site database created in BSCs
b) Correct LAC dimensioning; split LA if paging discard is due to big LA.
c) Define correct channel configuration for CCCH. Avoid combining SDCCH in the
BCH+CCCH timeslot.
d) Remove SDCCH congestion in network as page response is sent to network
through SDCCH.
e) Eliminate Abis /A interface congestion/error.
f) Correcting the various Paging/Location Update timers/parameters in
MSC/BSC/Cell.
g) Poor Paging Success rate is also observed due to poor RF environment (Site
outage/ Poor Signal Level etc.).
h) Use correct paging strategy according to network size and topology.
6.4.5 RACH SUCCESS RATE
Random Access Channel (RACH) is used by the MS on the ―uplink‖ to request for
allocation of an SDCCH. This request from the MS on the uplink could either be as a
page response (MS being paged by the BSS in response to an incoming call) or due to
user trying to access the network to establish a call. For all services there will CH REQ
(Channel Request) from MS and in the response of CH REQ if MS will get the IMM ASS
CMD (Signalling Ch) Access to system is successful. Nature of this Access REQ is
random so it is call Random Access Channel Request.
a) Identify the Bad performing Cells for RACH Success Rate
b) Take detailed report and analyze for no of failure of Request and failures.
c) The main reasons for bad RACH success rate could be access from very distant
place with very low coverage; Parameters Configuration discrepancies.
d) First Check for Parameters Configuration discrepancies and correct as per
standard parameter set.
e) The main parameters to be verified are:
I. ―MS MAX Retrans‖ allows the MS to retransmit again for AGCH by not
incrementing the RACH access failure counter. It can set depending upon Traffic
and Clutter.
II. ―Tx-Interger‖ will reduce the RACH collision and can improve RACH success
rate.
III. ―T3122‖ waiting time for next network access.
IV. ―RACH Min.Access Level (dbm)‖ very important parameter for low coverage
rural areas.
V. ―CCCH conf‖ & ―BS_AG_BLKS_RES‖ check properly defined or not? Because
if you have overload with AGCH ―IMM ASS‖ can‘t be send in the response of
CH REQ.
f) Check for Hardware Issues (Ex. BTS sensitivity has very crucial role to play here)
g) Check for Uplink Interference and quality.

i) Check for UL-DL imbalance and correct if any problem.

6.5 DATA KPI IMPROVEMENT
6.5.1 TBF SUCCESS RATE
Temporary Block Flow (TBF) is a physical connection used by the two Radio
Resource entities to support the unidirectional transfer of PDUs on packet data physical
channels. The TBF is allocated radio resource on one or more PDCHs and comprises a
number of RLC/MAC blocks carrying one or more LLC PDU. TBF Success Rate is when
during a data session, TBFs are successfully established on UL and DL.
a) Identify the Bad performing Cells for TBF Success Rate.
b) Identify the bifurcation of Poor TBF Success Rate: whether UL or DL is poor or it
is poor in both directions.
c) Take the detailed report showing (Ex. Total TBF Requests, Total TBF Success,
Failure reasons)
d) Identify the failure reasons after analyzing detailed report and follow the below
mentioned process.
Failure is mainly due to TBF Congestion or MS No response.
6.5.2 TBF CONGESTION:
i. Check the Static and Dynamic PDCH definition from BSC Configuration data) If you
find Zero Static or Dynamic PDCH, define the same.
ii. If PDCH definition is sufficient as per the guidelines, then check whether the TBF
requests are high. If requests are high, then we need to define more PDCHs in the
cell. But before defining more PDCHs, check whether the Voice Utilization is not
high and there is no TCH Congestion in the cell.
iii. Check Hardware/TRX alarms; Resolve if find any.
iv. Audit for any parameters related discrepancies and define as per standard parameters
set.
MS No Response: RF and Environmental Factors:
i. Low Coverage Areas (Try to reduce low coverage patches with physical
optimization; New sites)
ii. Interference/ Bad quality/ UL-DL Imbalance;
iii. Check the states for TRx on which PDCH is configured can be issue of TRx also;
Change TRx if you found random behavior of TRx.
6.5.3 AVERAGE GPRS/EDGE RLC THROUGHPUT
Throughput is the amount of data uploaded/downloaded per unit of time.
a) Identify the Bad performing Cells for Poor GPRS/EDGE Throughput.
b) Identify the bifurcation of Poor Throughput: whether UL or DL is poor or it is poor in
both directions.
c) Take the detailed report showing (Ex. Total TBF Requests, Coding Scheme
Utilization)
d) Identify the cells after analyzing detailed report and follow the below mentioned
process.
e) Take the configuration dump of the poor cells:
 Check The Static and Dynamic PDCH definition from BSC Configuration data)
 If you find Zero Static or Dynamic PDCH, define the same.

 If PDCH definition is sufficient as per the guidelines, then check whether the TBF
 Check whether there are enough Idle TS defined at the site. If not, definition to be
done.
f) Check whether it is due to poor radio conditions/interference; check C/I. Perform a
drive test to analyze the cell in more detail.
g) Check Gb Congestion/Utilization at the BSC/PCU.
h) Check Hardware/TRX alarms; Resolve if find any.
i) Audit for any parameters related discrepancies and define as per standard parameters
set.
6.5.4 DOWNLINK MULTI SLOT ASSIGNMENT SUCCESS RATE
User timeslot request based on traffic types and MS multi-timeslot capability and
the actual timeslot allocated by the system which can also be termed as Downlink
Multislot Assignment Success rate.
a) Identify the Bad performing Cells for Poor Poor DL Multislot Assignment.
b) Take the detailed report showing (Ex. Total TBF Requests, Failure in terms of TS
requests)
c) Identify the cells after analyzing detailed report and follow the below mentioned
process.
d) Take the configuration dump of the poor cells:
 Check The Static and Dynamic PDCH definition from BSC Configuration data)
 If you find Zero Static or Dynamic PDCH, define the same.
 If PDCH definition is sufficient as per the guidelines, then check whether the TBF
 Check the multiplexing thresholds and upgrade/downgrade reports.
e) Check whether it is due to poor radio conditions/interference; check C/I. Perform a
drive test to analyze the cell in more detail.
f) Check Gb Congestion/Utilization at the BSC/PCU.
g) Check Hardware/TRX alarms; Resolve if find any.
h) Audit for parameters related discrepancies and define as per standard parameters set.
6.6 3G UMTS KPI
6.6.1 3G KPIS ARCHITECTURE
Figure 48: 3G KPI Structure

RAN KPI Class :
Figure 49: 3G KPI Class

6.6.2 RAB ESTABLISHMENT SUCCESS RATE
This KPI describes the ratio of all successful RAB establishments to RAB
establishment attempts for UTRAN network and is used to evaluate service accessibility
across UTRAN. This KPI is obtained by the number of all successful RAB
establishments divided by the total number of attempted RAB establishments.
RAB Assignment is the last step of the service connection. If it is successfully

assigned, the connection to the user plane is successfully setup.
RAB setup procedure is the process that establishes the higher-layer connection
between UE and CN that is used to transfer the user data only (not signalling). When the
RNC receives the RAB ASSIGNMENT REQUEST allocates the necessary resources for
the requested service, after successful call admission. Resources include Codes, CE,
Power, IUB bandwidth. Then the RB is setup which is the UTRAN part of the RAB.
Upon successful completion of the RB setup, the RNC responds to the CN with
the RAB ASSIGNMET RESPOND message.

Figure 50: RAB Establishment

6.6.3 RRC CONNECTION ESTABLISHMENT SUCCESS RATE
This KPI describes the ratio of all successful RRC establishments to RRC
establishment attempts for UTRAN network, and is used to evaluate UTRAN and RNC or
cell admission capacity for UE and/or system load. This KPI is obtained by the number of
all successful RRC establishments divided by the total number of attempted RRC
establishments.
Figure 51: RRC Establishment

RRC setup procedure is the process that establishes the L3connection between UE
and RNC that is used for signalling traffic only. After RNC receives the RRC
CONNECTION
REQUEST, processes it and allocates relevant resources on L1, L2 and L3 ofthe air
interface for this signalling connection. The RNC notifies the UE for the prepared
configuration with the RRC CONNECTION SETUP message. The UE reports its
capabilities to the RNC with the RRCCONNECTION SETUP COMPLETE
6.6.4 CALL SETUP SUCCESS RATE/ SERVICE ACCESS SUCCESS RATE:
This KPI describes the ratio of successful call establishments. It is based on the
Successful RRC Connection Establishment Rate for callsetup purposes and the RAB
Establishment Success Rate for all RAB types. Both KPIs are multiplied.
Figure 52: RAB & RRC Establishment

The Call Set up Success Rate (CSSR) is one of the most important Key
Performance Indicators (KPIs) used by all mobile operators. The CSSR in general is a
term in telecommunications denoting the fraction of the attempts to make a call which
result in a connection to the dialled number.
6.6.5 UTRAN SERVICE ACCESS SUCCESS RATE
UTRAN service access success rate for idle mode UEs describes the ratio of all
successful UTRAN access to UTRAN access attempts for UTRAN network and is used
to evaluate service accessibility provided by UTRAN. Successful RRC set up repetition
and/or cell re-selections during RRC setup should be excluded, namely only service
related RRC setup should be considered.
This KPI is obtained by the Successful RRC Connection Establishment Rate for
UTRAN access purposes multiplied by the RAB Establishment Success Rate for all RAB
types.

6.6.6 UMTS PDP CONTEXT ACTIVATION SUCCESS RATE
This KPI describes the ratio of the number of successfully performed PDP context
activation procedures to the number of attempted PDP context activation procedures for
UMTS PS core network and is used to evaluate service accessibility provided by UMTS
and network performance to provide GPRS.
This KPI is obtained by successful PDP context activation procedures initiated by

MS divided by attempted PDP context activation procedures initiated by MS.
6.6.7 CALL DROP RATE
It is the most important indicators of the customers experience. It reflects the

retainability of the network.
The Call Drop Rate (CDR) is the fraction of the telephone calls which, due to
technical reasons, were cut off before the speaking parties had finished their conversation
and before one of them had hung up (dropped calls), this fraction is usually measured as a
percentage of all calls. This KPI describes the ratio of RAB release requests related to the
number of successful RAB establishment (per CS/PS domain).
Drops are derived from "IU Release Request" and "RAB Release Request
―messages sent from UTRAN to the CN as calculated by the formula:
6.6.8 CALL BLOCKING RATE :
This KPI indicate rate of blocked calls due to resource shortage. This KPI partially
reflects the degree of congestion in the cell.

6.7 MOBILITY KPI

6.7.1 SOFT HANDOVER SUCCESS RATE
This Indicate Radio link addition success rate. This KPI describes the ratio of
number of successful radio link additions to the total number of radio link addition
attempts.
This KPI is obtained by the number of successful radio link additions divided by
the total number of radio link.
Figure 53: Soft Handover

This indicator reflects the soft handover mobility in the RNC control area.
6.7.2 OUTGOING INTER RAT HANDOVER SUCCESS RATE (CS)
This KPI describes the ratio of number of successful inter RAT handover to the
total number of the attempted inter RAT handover from UMTS to GSM for CS domain.
This KPI is obtained by the number of successful inter RAT handover divided by
the total number of the attempted inter RAT handover from UMTS to GSM for CS
domain.

Figure 54: CS Outgoing Inter RAT Handover ( UMTS to GSM )

6.7.3 OUTGOING INTER RAT HANDOVER SUCCESS RATE (PS)
This KPI describes the ratio of number of successful inter RAT handover to the
total number of the attempted inter RAT handover from UMTS to GSM for PS domain.
This KPI is obtained by the number of successful inter RAT handover divided by
the total number of the attempted inter RAT handover from UMTS to GSM/GPRS for PS
domain respectively.
Figure 55: PS Outgoing Inter RAT Handover ( UMTS to GSM )

6.7.4 INTER RAT INCOMING HANDOVER ( PS )
This indicates the Inter-RAT handover mobility, the handover is from GPRS
system to UMTS system.
Figure 56: Incoming Inter RAT Handover ( GPRS to UMTS)
6.8 UTILISATION KPI

6.8.1 CS SERVICE TRAFFIC ERLANG
This indicator reflects the traffic Erlang of CS conversation service.
6.8.2 PS SERVICE THROUGHPUT
This indicator reflects total throughput of PS service.

6.8.3 UTRAN CELL AVAILABILITY.
A KPI that shows Availability of UTRAN Cell.Percentage of time that the cell is
considered available.
6.9 4G LTE KPI
As specified in the 3GPP TS 32.451 document, there are several types of KPI
parameters that are integral to any LTE network, depending on the target they measure:
 Accessibility
 Retainability
 Integrity
 Availability
 Mobility
Others can be added depending on the the network‘s need, such as:
 Utilization
 Traffic
 Latency
Accessibility
Accessibility is a measurement that allows operators to know information related
to the mobile services accessibility for the subscriber. The measurement is performed
through E-UTRAN‘s E-RAB service.
Retainability
Retainability measures how many times a service was interrupted or dropped
during use, thus preventing the subscriber to benefit from it or making it difficult for the
operator to charge for it. Therefore, a high retainability is very important from a business
stand point.The measurement is performed through E-UTRAN‘s E-RAB service.
Integrity
Integrity measures the high or low quality of a service while the subscriber is
using it.The measurement is performed through E-UTRAN‘s delivery of IP packets.
Availability
Availability measures a service‘s availability for the subscriber. The measurement
is performed by determining the percentage of time that the service was available for the
subscribers served by a specific cell. The measurement can also aggregate data from more
cells or from the whole network.

Mobility
Mobility measures how many times a service was interrupted or dropped during a
subscriber‘s handover or mobility from on cell to another. The measurement is performed
in the E-UTRAN and will include Intra E-UTRAN and Inter RAT handovers.
KPIs for LTE RAN (Radio Access Network)
LTE KPI INDICATORS
 RRC setup success rate

 ERAB setup success rate
 Call Setup Success Rate
Accessibility KPI Are used to measure properly of whether services requested by
users can be accessed in given condition, also refers to the
quality of being available when users needed. eg. user request
to access the network, access the voice call, data call, ......
 Call drop rate

 Service Call drop rate
Retainability KPI
Are used to measure how the network keep user's possession or
able to hold and provide the services for the users
 Intra-Frequency Handover Out Success Rate
 Inter-Frequency Handover Out Success Rate
 Inter-RAT Handover Out Success Rate (LTE to
Mobility WCDMA)
KPI
Are used to measure the performance of network which can
handle the movement of users and still retain the service for the
user, such as handover,...
 E-UTRAN IP Throughput
 IP Throughput in DL
Integrity  E-UTRAN IP Latency

KPI
Are used to measure the character or honesty of network to its
user, such as what is the throughput, latency which users were
served.
 E-UTRAN Cell Availability
Partial cell availability (node restarts excluded)
Availability
KPI
Are used to measure how the network keep user's possession or
able to hold and provide the services for the users
 Mean Active Dedicated EPS Bearer Utilization
Utilization
KPI Are used to measure the utilization of network, whether the
network capacity is reached its resource.
Table 17. LTE KPI

6.9.1 RRC SETUP SUCCESS RATE
RRC setup success rate is calculated based on the counter at the e-NodeB when
the e-NodeB received the RRC connection request from UE. Number of RRC connection
attempt is collected by the e-NodeB to the measurement at point A, and the number of
successful RRC connection calculated at point C. Here's an illustration:
Figure 57: RRC Setup
Table 18. RRC Setup Success Rate

6.9.2 ERAB SETUP SUCCESS RATE
ERAB setup success rate KPI shows the probability of success ERAB to access all
services including VoIP in a cell or radio network. KPI is calculated based counter ERAB
connection setup attempt (point A) and successful ERAB setup (point B). The
explanation is as given in the following illustration:

Figure 58: ERAB Setup
6.9.3 CALL SETUP SUCCESS RATE
Call Setup Success Rate KPI call setup indicates the probability of success for all
service on the cell or radio network. KPI is calculated by multiplying the RRC setup
success rate KPI, S1 signalling connection success rate KPI, and ERAB success rate KPI.
The table below describes the definition Call Setup Success Rate:
Table 19. CSSR

6.9.4 CALL DROP
VoIP call drop arise when VoIP ERAB release is not normal. Each ERAB
associated with QoS information. Here's an illustration of two procedures being done to
release ERAB namely: ERAB release indication and the UE context release request:

Figure 59: ERAB Setup
6.9.5 INTRA-FREQUENCY HANDOVER OUT SUCCESS RATE
Intra-Frequency Handover Success Rate Our KPI shows intra-frequency handover

success rate of local cell or radio network to the intra-frequency neighboring cell or radio
network. Intra-frequency HO included in a single cell e-NodeB or different e-NodeB.
Intra-frequency HO scenario shown in the figure below:
Figure 60: Intra-Frequency Handover Out

No attempt HO calculations at point B. When E-NodeB sending RRC connection
reconfiguration message to the EU, he will do the handover. E-NodeB will count the
number of times the HO attempt at the source cell. HO calculation of success is at point
C. The HO E-NodeB count the number of the source cell when E-NodeB receive RRC
connection reconfiguration message complete of the EU. Here's a scenario intra-
frequency handover inter E-NodeB

Figure 61: Intra-Frequency Handover inter E-NodeB

Handover attempt occurs at point B, when the source E-NodeB (S-e-NodeB)
sends RRC connection reconfiguration message to the UE. He decided to conduct inter E-
NodeB HO. in this KPI, the source and the target cell work on the same frequency. The
number of the attempt HO calculated at the source cell. The number of successful HO
occurs at point C. During HO, HO amount which success is measured in the cell sauce.
This measurement appears typing S-e-NodeB received a UE context release message
from the target eNode B (T-e-NodeB), or the UE context release command from the
MME, which shows that the UE-e-NodeB T has successfully attach at the T-e-NodeB.
The following scenarios illustrate intra frequency B HO - inter E-NodeB:
Figure 62: Intra-Frequency Handover inter E-NodeB

Following the definition of Intra Frequency Out Handover Success Rate KPI:

6.9.6 INTER-RAT HANDOVER OUT SUCCESS RATE (LTE TO WCDMA)
Inter RAT Handover Out Success rate shows the success rate KPI HO from LTE
cell or radio network to a WCDMA cell.
Here's a scenario out inter RAT handover success rate:
Figure 63: out inter RAT handover

Inter RAT handover success rate out

6.9.7 E-UTRAN IP THROUGHPUT
A KPI that shows how E-UTRAN impacts the service quality provided to an end-
user. Payload data volume on IP level per elapsed time unit on the Uu interface. IP
Throughput for a single QCI:
Figure 64: E-UTRAN IP Throughput

To achieve a throughput measurement that is independent of bursty traffic pattern,
it is important to make sure that idle gaps between incoming data is not included in the
measurements. That shall be done as considering each burst of data as one sample.
ThpVolDl is the volume on IP level and the ThpTimeDl is the time elapsed on Uu for
transmission of the volume included in ThpVolDl.

Figure 65: E-UTRAN IP Throughput

6.9.8 E-UTRAN IP LATENCY
A measurement that shows how E-UTRAN impacts on the delay experienced by

an end-user. Time from reception of IP packet to transmission of first packet over the Uu.
To achieve a delay measurement that is independent of IP data block size only the first
packet sent to Uu is measured. To find the delay for a certain packet size the IP
Throughput measure can be used together with IP Latency (after the first block on the Uu,
the remaining time of the packet can be calculated with the IP Throughput measure).
Figure 66: E-UTRAN IP Latency

T_Lat is defined as the time between receiption of IP packet and the time when
the e-NodeB transmits the first block to Uu. Since services can be mapped towards
different kind of E-RABs, the Latency measure shall be available per QoS group.
AVAILABILITY KPI:

6.9.9 E-UTRAN CELL AVAILABILITY.
A KPI that shows Availability of E-UTRAN Cell.Percentage of time that the cell is
considered available.
As for defining the cell as available, it shall be considered available when the e-
NodeB can provide E-RAB service in the cell.
6.10 CONCLUSION
It is very important to manage KPI of radio network in order to have best of radio
network performance.

E3-E4 Consumer Mobility Mobile Sales Managment and Sancharsoft
7 MOBILE SALES MANAGEMENT (BCCS, FRANCHISE

MANAGEMENT, SALES CHANNEL MANAGEMENT
AND SANCHARSOFT)
After completion of this chapter participants will understand:
 Billing process in CMTS
 Billing System Components
 Billing Procedures
 BSNL Sales Structure
 Sancharsoft
7.2 BASIC FEATURES OF MOBILE BILLING NETWORK
 The GSM Cellular network includes a state of art billing and customer care system
supporting several customer friendly features. The Network is identified as local
access in the entire licensed service area as against the SDCA based local area. The
components of the Mobile Billing have different elements like airtime charges,
roaming charges, messaging charges, and value added service charges apart from
PSTN charges for inter network traffic.
 There are other differences like the concept of a prepaid and post paid. It is envisaged
that the volumes in case of prepaid services will be more than the post-paid services.
Further there would be a dealer and distributor network in place, which would be a
significant activity in terms of interaction with the billing system.
 While considering the design, structure and organizational framework, there is a need
to have a system that incorporates efficient practices. It is very important to
incorporate the responsibilities attached to the activities of commercial and financial
nature at appropriate levels.
7.3 BCCS HARDWARE
 The Mobile network consists of zonal Billing and Customer Care System (BCCS)
catering to more than one licensed service area. The BCCS will have CSR (Customer
Service Representative) terminals that will be stationed in different locations across
the circle. A CSR terminal can also be networked through a Local Area Network to
enable a number of persons to key in data and work in the system. These terminals
have capabilities to interact with the BCCS in respect of provisioning, billing,
collections and trouble ticketing.
 While CSR terminals can provide varied functions, access to these functions is
controlled through defining the roles of each terminal and also depending on level of
staff and officers manning such terminals. Normal functions such as data feeding,
creation of account, trouble ticketing and generation of duplicate bill shall only be
available at front-end Basic Level CSRs. All other functions such as service
provisioning, activation, billing etc. shall be handled at terminals designated as High
Level CSRs.
7.4 MOBILE BILLING AND CUSTOMER CARE COMPARED TO
BASIC SERVICES
The activities will be dependent on the nature of system design and operations.
This essentially consists of a centralized Billing and Customer Care System (BCCS)
through which are linked a number of CSR terminals located all over the circle and across
different circles in a zone. These terminals have the facility to enable multifarious
activities like provisioning, creation of customer information, billing, interacting with

billing system, collections, reports, trouble ticketing, querying on various aspects. Unlike
basic services, various commercial, billing and accounting functions are integrated in a
single system using shared common database of customers, service subscriptions etc. This
would enable overcoming the inherent coordination problems faced hitherto, by virtue of
having easy access to the common database for various functional needs from the CSR
terminals. This facilitates CMTS business units to have an organization and a system,
which can be managed by a flat and a non-hierarchical set up.
7.5 BASIC CONCEPTS
 Network Access to BCCS from CSR.
 Network access from CSR terminals can be segmented to serve a particular part of the
service area, a group of MSISDN (Mobile Subs) etc on the basis of the specific
criteria. This feature would enable CSRs to be assigned to deal with specific
geographical segments.
 CSR would have functional segmentation, assigning specific functions to particular
CSR terminals. For example, a CSR could be assigned only for order entry and
querying on bills.
 Regulated and buffered access for the channel partners, as and when so decided.
(Channel partners are the Dealers and Distributors appointed for promoting CMTS).
7.6 ACTIVITIES AND RESPONSIBILITY CENTRES
 GSM Mobile network includes a state-of art Billing and Customer Care System
(BCCS) supporting several customer friendly features. Apart from capturing the
billing related data, the BCCS also integrates a data communications network with
Customer Support Representative (CSR) terminals spread across the entire zone.
CSR terminals are conceived to be the gateways for accessing the sophisticated
facilities built into the BCCS for providing quick and complete customer care. Some
of the salient features of the CSR are:
 On-line creation of Account and support for hierarchical account creation with parent-
child relationship.
 On line creation, suspension, withdrawal of service including provisioning, addition,
modification, suspension and withdrawal of a host of supplementary and value added
services.
 Complaint management.
 Contract management
7.7 ROLE OF CUSTOMER SERVICE CENTERS (CSCS)
 CSCs of BSNL would provide excellent visibility for the mobile service.
 CSCs are to serve as direct sales outlets of BSNL but not to be predominant avenues
for BSNL mobile products. There has to be synergy in operations with Channel
partners.
 Service and product marketing, to a large extent, would be channel driven.
 Channel partners to provide first level customer care with well-defined multi-level
escalation procedures.
 CSC locations to facilitate market intervention by BSNL and to regulate the conduct
of the channel partners.
 CSC to play a vital role in the Brand building exercise and not primarily as sales
outlet.
7.8 ROLE OF CSRS
Basic level CSR in CSCs shall address primary customer needs i.e. receipt of
order forms and feeding them, handling customer queries for services, sale of prepaid

cards, issuance of duplicate bills, trouble ticketing etc and handling other requests for
facility provisioning and counseling on tariff plans. Higher-level CSR shall address in
addition to basic functionalities, the service provisioning aspects, activation, billing etc
and transactions with Channel partners.
7.8.1 CSR LOCATION
 Basic level CSR to be located in the CSCs. These CSRs shall be under control of an
officer/official not below the rank of Group C.
 Higher level CSRs to be located at the SSA HQs. These terminals will handle
responsible activities, which are elaborated subsequently. They will also provide
support for the channel partners. The extent of deployment shall match the response
time specified for the channel partners. These CSRs shall input the data received
from channel partners in batch mode. These CSRs shall be under control of an officer
not below the rank of Group B. An officer with suitable aptitude and credentials may
be selected.
7.8.2 CSR FUNCTIONALITIES:
 Any terminal connected to BCCS through CSR can be designated to handle any type
of Commercial, Billing & Accounting and Customer Care activities / functionalities.
The functionalities will include commercial & customer care activities like receipt of
application forms, feeding them, activation of accounts after verification of credit
limits, activation of pre paid cards, handling of customers‘ queries and trouble
ticketing on services and tariff and billing functionalities like printing of bills, issue of
duplicate of bills, bill modifications / corrections wherever necessary, receipt and
accounting of payments, watching of payments and taking follow up action wherever
payments are not made, authorising disconnections for non payments and
reconnections, follow up action for recovery of outstanding dues of disconnected lines
and, preparation of accounting statements to a limited extent, customers‘ record
updation regarding payments etc.
 Considering the accessibility to all types of functionalities from CSR terminals, access
to information based on the level and role assigned to the user, would be restricted
through suitable login and password.
7.9 CIRCLE (LICENSE AREA) LEVEL
The circle for CMTS Services would normally be the license area. In many cases,
the area of CMTS circle would be different from that of basic services. Since CMTS
Circle is identified as SBU (Strategic Business Unit) there will be a responsibility centre
at the Circle Level which will get sub-ledger reports for all units generated by the system,
giving information on monthly billings, collections, revenue per line, revenues from pre-
paid cards, statements for revenue sharing with other service providers/carriers etc,
collection efficiency, reduction of outstanding, clarification on billing and collection
matters. Co ordination and control unit for mobile operations comprising GM (Mobile
services), DGM (Finance) of CMTS, Marketing and Commercial officers shall form part
of the same to review and handle all issues relating to billing and collection mechanism.
This set up will also carry out revenue-tariff correlation analysis and propose tariff
rebalancing / product repositioning / product repackaging proposals to Corporate office
for consideration. Circles will also propose implementation schedule (i.e. dates of
launching of alternative packages and their currency). Different tariff plans approved for
various circles shall be implemented on dates and during periods as approved by
corporate office.

7.10 COMMERCIAL PROCEDURES

Commercial procedure would involve acquisition of customer, their registration,
handling of address audit/verification and on satisfactory completion of the same to
activate with suitable service provisioning. Each of these issues is discussed in the
following paragraphs:
7.10.1 REGISTRATION
The registration of any customer is through a prescribed order form duly filled in
and signed by the applicant The order form contains the following details:
 Customer name
 Billing address
 Tariff plan
 Deposit / Payment information
 Demographic information as prescribed
 Optional services opted for i.e. STD, ISD, Roaming etc.
 Whether an Individual/Corporate/Government (Central/state) etc.
 Purpose of use (Business / Personal)
 Hand set information
 Income Tax Permanent Account Number
 Details of existing services of BSNL being availed of.
 Photograph of the applicant
 Particulars of the introducer/ local reference.
7.10.2 PROCEDURE FOR REGISTRATION BY CSR/CHANNEL PARTNERS
The order form shall be accepted only at CSRs / designated outlets located in the
SSA, where the prospective customer wants to get the connection registered. The
prospective customer‘s order for prepaid/postpaid can be classified as under:
 Already a BSNL customer and has produced the latest bill with proof of payment, and
has no outstanding dues.
 Credential needs to be established through authentic central and state government
identity documents like PAN, ration card, Driving license, Passport etc.
 The outlet issues receipt acknowledging the order and hands over the SIM.
 Where the credentials are beyond doubt, the activation request may be accepted at
Higher Level CSR terminal from a designated mobile phone whose CLIP
authenticates the source of request.
 Where address audit/verification with basic service Commercial / TRA unit is
involved, the same is to be done expeditiously by the outlet and confirmation obtained
within 24 Hrs.
 The order forms duly recommended by the dealer‘s network regarding the credentials
of the customer shall reach the designated CSR terminal for activation on daily basis.
 The payments collected by dealers shall be remitted to the CSR on a daily basis. All
collections received by Dealers during the day shall be deposited by with CSR latest
by 12:00 Hrs. next morning, who in turn shall remit all collections of the center
including receipts from Dealers to AO (Cash) on the same day.
 Reconciliation of connections activated and payments collected shall in no case be
delayed beyond 24 hours and will be done by Higher Level CSR who will send a
weekly report to AO (CMTS). AO (CMTS) shall carry out a test check on monthly
basis and submit a report to the IFA / GM (CMTS).
 An acknowledgement for registration of the connection shall be issued in the first bill
through a message to this effect and the payment of the first bill is considered as the

acknowledgement for receipt. A registration confirmation will be sent through SMS

after activation.
 All activations must take place within the same day of receipt of Cheque / DD / Cash
at any of the CSRs.
7.10.3 VERIFICATION
 A process of post verification of customers is essential for all customers depending on
the category
 The process of verification in each of these cases is further elaborated below:
 The customers seeking connection categorized under 3.2.2 (a) above are existing
BSNL customers who have established their identity and credibility through a copy of
the payment receipt of latest bill. The connection of such customers can be activated
forthwith giving a credit limit equivalent to security deposit amount (or as fixed by
BSNL from time to time). However, address audit and paying habit verification with
TRA/Commercial Wing need to be got done in a time frame of not more than 24
hours and services as asked for can further be provided. The credit earlier limited to
the security deposit amount (or as fixed by BSNL from time to time) may be updated
after this verification as per Para 3.5.
 In case of 3.2.2(b) above, a process of post-verification of customers must be
introduced. This service can be outsourced in addition to internal efforts by way of
verification of fixed line details, credit card, PAN card, etc. Address verification and
credit worthiness can be got done by such agencies, who have done similar work for
Credit Card Organisations / other specialized agencies working in this field. Such
agencies must submit the verification report within 24 hours from the time of
assignment.
 The system shall permanently store the information about the official & dealer/agent
who screens and passes the customer details verification.
7.10.4 SECURITY DEPOSIT
Appropriate Security Deposits (for optional facilities like
STD/ISD/National/International Roaming and Other services) as required to be taken
from time to time as per corporate office orders shall be collected to minimize losses on
account of defaults in payments. Appropriate accounts of the Security Deposits thus
collected, shall be maintained on a monthly ledger basis, in the same manner and details
as for fixed line deposits, so as to depict BSNL‘s liability on this account.
7.10.5 CREDIT LIMITS
Post address verification Credit limit of a customer may be fixed as given in the
table below or as prescribed from time to time, for the period, till the report of the credit
rating agency is received. This limit is restricted to the credit limit opted for by the
customer.
Individual 1 x SD
Business 3 x SD
Corporate 4 x SD
7.10.6 SD: SECURITY DEPOSIT
 However this credit limit shall be altered, on a written request from the customer and
after verification of past payment habits, credentials based on the customer profile and
recommendations on the credit limit given by the Credit Rating Agency. This limit is
restricted to the credit limit opted for by the customer.
 The system shall be so configured so as to maintain full details of approval of Credit
limits higher than that recommended above including the particulars of the system

operator—login. GM (CMTS) shall accord the approval for such enhancement of

credit limits in consultation with IFA to GM (CMTS).
7.10.7 MODE OF PAYMENT OF REGISTRATION AMOUNT
Payment may be accepted by cash/cheque(local clearance only)/DDs/Credit Card /
Debit cards at both the company‘s and dealer‘s outlet. In case of cheque payment credit
limit will be equal to security deposit or Rs.1000/- whichever is lower. In case cheque
bounces the following steps are to be adopted by the concerned CSR, who shall receive
the information from AO (Cash):
 SMS message is to be sent to the defaulter within 24 hours asking him to make
cash/DD payment within next 48 hours.
 Only cash or DD shall be accepted for this payment from the customer.
 Services of the defaulting customer shall be disconnected if payment is not received
within the prescribed time.
 The re payment shall be made only at the same SSA where customer had originally
paid the cheque.
 In cases where the bounced cheques were received from dealer/ distributor, the onus
of loss, if any, shall lie with the channel partner.
7.10.8 PROVISIONING
 The applications received at various customer service centres and dealers shall be sent
to the Higher Level CSR, wherein the functions of provisioning, billing and
accounting would converge with reference to all such customer service centre and
dealers falling in their jurisdiction.
 All commercial records uniquely to be identified by a customer code which is also
assigned by the billing system for each of the post paid customers shall be kept at
SSA HQs under the custody of a Gazetted officer at least of Group ‗B‘.Electronic
copy of the same may also be stored for any future references.
 If the customer service centre is located in the same city the order forms shall be
delivered twice a day at an identified time, irrespective of the volumes. For
outstations cases the order form shall be delivered at least on a daily basis. The order
forms along with the documents can also be faxed by basic level CSR of the
concerned area so that the higher level CSR can complete the activation.
 After receiving the forms, the following shall be done:
1. Application scrutiny
2. Address verification
3. Customer credit worthiness
4. Fixation and alteration of credit limit
Validating and acceptance of the data and information in the system has to be
carried out by an official of Group B and above.
 In due course terminals can be provided at various customer service centres and even
at dealers‘ premises for feeding in the information. However accepting the
information into the system will be the responsibility of the officer concerned at
Higher Level CSRs. Provisioning would be done after the original order form of
prospective customers are received along with the requisite documents for
registrations at the Higher level CSR. For registrations by Basic Level CSRs the
provisioning will also be done on receipt of documents by fax (to be followed with
original). Help of Courier service etc. can be availed for quicker delivery to ensure
timely provisioning. The Basic level CSR will send documents by fax to be followed
with original, duly signed and authenticated. The cases where activation is done based
on fax messages, the original documents has to reach the Higher Level CSR within 48

hours. This will be the responsibility of the Originating CSR. However, if the
documents are not received, within the stipulated time frame, the Higher Level CSR
must immediately follow up with Basic Level CSR and take further necessary action.
 The higher-level CSR will ensure that the gap between activation of a connection and
address audit / credit verification does not exceed 48 Hrs and keep a record of the
same. GM (CMTS) or any officer so designated by him may carry out a periodical
check of the same and take follow up action on the same.
 Cases where the address verification report and Credit Rating Report is not
affirmative, the connection should be closed with the approval from GM (CMTS).
7.11 BILLING CYCLES AND DIS-CONNECTIONS
7.11.1 BILLING
 The periodicity of billing shall be monthly. Interim bill / hot bills may be raised by
Accounts Officer based on such need as may arise either on account of usage or
request by the customer.
 Bills shall be generated dated 1st of each month taking the CDRs (Call Detail
Records) up to 2400 Hrs on the last date of the previous calendar month.
 The bills will be generated at the Zonal BCCS and will be printed at TRA of SSA
concerned. The bills may also be alternatively printed at the level of Circle, if so
decided by the circle concerned.
 The Accounts Officer (TR) will check the bills printed on a sample basis. After
checking, the bills shall be dispatched. The maximum time between bill printing and
dispatch shall be 48 Hrs.
 SMS message shall be sent to all customers informing them of bill dispatch and
amount of the Bill Due date for payments will be 15th of the same month. The same
will be done by the AO concerned responsible for bill printing and dispatch.
 Second SMS shall be sent on 18th day of the month, in the form of a reminder to the
customers whose payments have not been received till that date
7.11.2 CHARGING OF RENT
 Charges for airtime and facilities like roaming, CLIP and any other value added
services should be billed in arrears, or as per the policy of BSNL decided upon from
time to time.
 Rental charges shall be billed in advance for the period of one billing cycle, i.e. one
month. However rental charges from the date of provisioning to the last day of the
previous month has to be necessarily charged in arrears.
7.11.3 INCENTIVE / SURCHARGE ON PAYMENTS
 To encourage early payments, healthy payment habits and to ensure effective revenue
realization mechanism, the customer may be given an early payment incentive as per
the policy of BSNL to be decided upon from time to time.
 In case of payments after 15th i.e. the due date, a surcharge at prescribed percentage of
billed amount can be levied.
 Customer can also make part payment. In case of part payments the surcharge will be
levied on the balance amount.
 No incentive will be due on part payments.
 Incentive / surcharge will be included in the next bill.
 The bills shall accordingly present all relevant details of charges (i.e. normal,
discounted and with surcharge) together with concerned dates.
7.11.4 BILL FORMAT
There will be one bill format for the entire country.

 The bill will carry information with reference to monthly fixed charges, usage
charges, discounts and incentives if any, misc. charges, pending payments, if any,
taxes and levies if any. Breakup of the net amount claimed must be disclosed on the
bill.
 Bills will carry bar code, the format of which will be the same as the format that has
been used for the fixed services.
 The bill format will also have a specific area for advertising and marketing schemes
such as, reward schemes to encourage customers‘ loyalty to BSNL.
7.12 COLLECTION OF BILLS
The following modes of payments will be used.
7.12.1 CASH PAYMENTS
 At Collection centers of BSNL presently in operation during the normal working
hours.
 Through authorized nationalized / private banks till the due date of payments as and
when authorized.
 Post offices till the due date of payments. (Annexure VI)
7.12.2 CHEQUE PAYMENTS
Cheque depositing machines shall be encouraged on a large scale, as a convenient
service for payment facility round the clock. Banks: Nationalized and private banks.
 Banks shall receive payments and remit the same in a similar manner as per prevailing
practice in case of fixed line services. However, the vouchers and statements shall be
remitted in a pre-determined format—acceptable to the billing system in a soft copy.
 In such locations where the available banker is not in a position to give the data in
required format, manual lists carrying all details already specified for fixed line
telephones shall accompany vouchers to be remitted to BSNL.
 Wherever the banks included in the collection scheme have corporate account of
BSNL, the money shall be credited to BSNL through the account. In other cases the
daily collections shall be remitted by way of a bankers‘ cheque on a daily basis.
 Drop boxes for cheque payments shall be encouraged at various locations like the
ATMs of banks, Railway Stations, customer service centers, Telephone exchanges,
BSNL mobile dealers, STD PCOs and other secure places. There shall be separate
drop boxes preferably with different colors to segregate the bills of basic and mobile
services.
 Bill collection through dealers: The dealer could have drop boxes for cheque
collection and they shall forward cheques on daily basis along with a signed list to
AO (Cash), BSNL. In case of receipts of payments by cheque on common counters
for PSTN and mobile services, separate cheques will have to be drawn for the time
being. This may however be changed after such integration of two databases.
 Payment through Post Offices: The payments can be accepted through Designated
Post Offices up to the due date.
 Payment through Internet: Payment of bills through Internet shall also be accepted in
the same manner as has already been introduced for fixed line.
 Payment through debit and credit cards: Payments shall also be accepted through
credit cards. The customers shall be given the options for direct debiting of bills to the
credit cards after giving a mandate to this effect.
 Payment by post: Cheque payments through post shall also be accepted. Customers
may send such cheques to AO (Cash) of the concerned of the SSA, who in turn remits
the same to bank and sends a statement to AO (CMTS) / CSR designated for updating
customer database i.e. data entry of paid vouchers.

 Payment at ATMs: Payments shall also be accepted at ATMs of certain banks, with
whom an agreement to this effect shall be entered into by BSNL.
 Payment through ECS: Payments through ECS shall be accepted wherever the facility
is available with the banks.
7.13 REALIZATION / DISCONNECTION / RECONNECTION
All activities of disconnection and restoration shall be carried out from the same
terminal of Higher Level CSR, which is enabled for activation.
a) Payment updation in customer’s record.
 AO (Cash) of the SSA shall accept payments from customers at various designated
points / centers under his control, and mobile collections list from other collection
channels, and account for the same on daily basis in the collection cash / bankbook.
AO (cash) will send on daily basis a list of mobile services collections to Higher
Level CSRs and AO (CMTS) for validation and updation of customer records
respectively.
 AO (TR)/CSR shall ensure payment up-dation in customer‘s record, on daily basis on
receipts of such lists from AO (Cash). (Annexure 8)
 AO (Cash) will send a daily Cheque Dishonour Statement to the Higher Level CSR
who in turn will send the intimation to the Lower level CSR. The same information
shall also be sent to AO CMTS. The CSR/AO (CMTS) shall accordingly modify /
update the payment particulars in the system. (Annexure 7)
b) Disconnections for Non Payment: To be monitored and authorized by AO
(CMTS)
 SMS message, as a reminder shall be given to the customer on 18th day. In case of
non-receipt of payments by 21st day, the outgoing facility will be withdrawn, and
customer will be intimated through a SMS. If payment is not received by 26th day, the
incoming facility will also be withdrawn.
 Services shall be withdrawn immediately upon receipt of written request from the
customer to this effect.
 A credit limit shall be fixed for all customers based on the calling profile and calls
may be restricted based on his/her credit limit/ option.
 A record of disconnection activity shall be maintained on the system itself, and a
report of the activity shall be generated on monthly basis for revenue monitoring by
management.
 In case of cheque dishonor the process already described vide 3.6 a to 3.6 c above
shall be followed. However the Outgoing or any other optional facilities provided to
the customer shall be immediately withdrawn on the receipt of Cheque Bounce
information.
c) Reconnection after clearance of dues
 In case of payments being received at basic level CSRs who are not enabled for
restoration, the information of receipt will immediately be sent by fax to Higher Level
CSR, who may immediately restore the facility and intimate AO (TR) accordingly.
 Whenever the full payment is received through other channels , the AO (TR) will
authorize the officer of the activation center of the Concerned SSA to reactivate the
connection and ensure the reconnection during the same day. Reconnection charges if
any shall be included in the next bill.
d) Follow up of outstanding dues in closed cases.
 Existing procedure for recovery of outstanding dues will be generally followed in
closed cases of mobile services as well.

 In case of defaults in excess of Rs. 10,000, a BSNL official duly authorized must visit
the customer‘s premises within 15 days and submit a report.
e) Write off of outstanding dues in closed cases.
The existing procedures for Fixed Line operations of BSNL shall apply mutates
mutandis.
7.14 BILLING AND OTHER COMPLAINTS
The AO (CMTS) will deal with the bill related, payment or adjustment
related complaints. In case of mixed complaints, AO or CO depending on the main cause
of the complaint will handle the complaints.
7.15 CLOSURES AND REFUNDS
 A request for closure / surrender may be received from the customer on a plain paper
at any of the CSRs or at the Dealers‘ location.
 The application shall be forwarded to higher level CSR on the same day.
 The Number shall be immediately closed by Higher-level CSR on receipt of such
application, after due authentication of the request, and the application will be
forwarded to AO (CMTS) for processing refunds.
 AO (CMTS) shall process a final bill and close the accounts within one week.
 The AO (CMTS) will issue sanction for refunds, wherever due, within two weeks
from the date of closure, or issue of next bill, whichever is earlier. In case of customer
having roaming facility, the refund must be made within 4 weeks after adjusting
roaming charges. The AO (Cash) will honour such sanctions and account for the same
in the book of accounts. The next higher authority to the sanctioning authority shall
review a monthly review of refunds sanctioned. The entire process shall be completed
within 4 weeks from the date of closure.
7.16 COMMISSION TO DEALERS / DISTRIBUTORS /
FRANCHISEES
Commission to channel partners shall be decided as per policy laid down by
BSNL Corporate Office from time to time. AO (CMTS) shall examine the amounts due
based on the inputs from the Billing System or the Marketing Units. GM / DGM / In
charge Marketing of the CMTS Unit as the case may be, shall sanction the commission to
be paid.
7.17 COMPLIANCE OF SALES / SERVICE TAX
As regards the compliance of the provisions of Sales / Service Tax Act and the
rules framed there under, AO (CMTS) shall take all necessary steps as per instructions
issued from time to time by the Corporate Office / Zonal office / circle Office. The AO
(Cash), SSA will remit the service tax collected from time to time and maintain full
records of the same.
7.18 INTERCONNECT SETTLEMENT
A designated officer will coordinate for Interconnect Settlement with other
Network operators/ Service Providers, including receiving and sending roaming details
from and to other operators, wherever direct links are established with BSNL CMTS
Circles and roaming agreements exist. After obtaining necessary details, the settlements
shall be processed by AO CMTS. AO CMTS will ensure proper accounting settlements
with all other operators/service providers.
7.19 CONTROL MECHANISM FOR PREPAID CARDS
 Pre paid services shall be offered through Intelligent Network platform. The
recharging of the account shall be done through rechargeable coupons, each having
specific amount. The rechargeable coupons, when printed, are equivalent to cash and

shall be handled scrupulously and accounted for meticulously. The coupons as and
when printed though not equivalent to cash, do represent value and shall be handled
scrupulously, with the same concern as cash, stamps and cheques and shall be
accounted for meticulously.
 In order to have an effective control of the system, there needs to be material and
financial accounting simultaneously. The steps that are required to be followed are as
follows:
1. Each and every coupon printed in BSNL must bear a unique Number.
2. The printing of pre-paid coupons will be at the IN platform in each zone / circle (if
security aspects permits). Since there will be a large number of distribution points the
Systems Manager(s) at the IN platform or Network Support Services (NSS) will deal
with each circle as a unit.
3. NSS shall maintain complete physical record of the printing and distribution, in the
format as prescribed at annexure I and II
4. One copy of the report mentioned above shall be sent to AO (CMTS) of the circle by
NSS in charge, in respect of coupons printed by them.
5. Marketing will also be preparing a statement as described in Annexure III describing
the consolidation of issues/Sales to CSRs, and other channel partners.
6. All CSRs will send daily sales information to AO (Cash) of the SSA, who in turn will
consolidate the statement for the entire SSA, and send the information to AO (CMTS)
For this purpose CSR and AO (Cash) shall follow annexure iv.
7. Marketing in charges shall prepare a statement on daily basis detailing the sales
effected, and balance of stock as described in Annexure V and send the same to AO
(CMTS).
8. Distributors, who may be authorized for sale of pre paid cards, shall be issued cards
against their demand, after full payment of the net value of cards.
9. Distributors who may be authorized for sale of pre paid cards, shall submit the
particular of sales, giving all information as mandated by statutory requirements to be
duly endorsed by BSNL from time to time, to the marketing in charge / channel co
coordinator. Such records shall be maintained by concerned marketing divisions in
their offices, under control of marketing in charge / channel co coordinator.
10. Marketing strategy may involve giving away of pre paid coupons as gifts. For this
purpose, on the basis of sanction of competent authority, pre paid coupons will be
given to designated officers of marketing / other units as imprest and shall be
accounted for accordingly, by AO (Cash). Full particulars shall be given to AO
(CMTS) for cards issued for promotional purposes and should be accounted for as
marketing expenses.
11. All designated officers who are issued Pre paid cards for promotional purposes under
various schemes, shall submit detailed statement clearly showing the utilization of
cards, along with the name of scheme, S No of cards, denomination and person /
agency to whom it was issued, along with account of imprest. One copy of such
statement shall also be maintained by marketing wing for assessment of various
schemes. These shall be accounted for AO (CMTS) through a journal entry.
12. IFA of the circle will arrange to conduct quarterly audit of card generation system,
and also physical verification of stocks with the marketing wing.
13. IFA of the circle will also arrange to conduct a physical audit of the inventories like
Handset, SIM cards that are procured and utilized for the operational needs of CMTS.
Necessary control mechanism for SIM Cards may be devised by GM CMTS /
Circle in the above lines and shall be reviewed periodically.

7.20 SUB LEDGER ACCOUNT

 There will have to be a sub ledger as in case of fixed line telephone services to give
analysis of outstanding for various units. The components of sub-ledger would be
different in case of mobile services. The format of sub ledger shall be as give in
Annexure B. The CAO (CMTS) at the Zonal Billing Centers shall generate all
accounting statements on a monthly basis and remit the same to corporate office by
10th of succeeding month. AO (CMTS) of the circles shall prepare sub ledger
statements in the prescribed format, based on accounting reports from the BCCS
system and statements received from all AO (Cash) of SSAs, and submit the same to
Corporate office by 10th of succeeding month.
 Separate Collection and remittance accounts for mobile services has to be maintained
by AO (Cash).
7.21 ACCOUNTING
The Units where Accounting will have to be done
The Accrual method of accounting, in keeping with the Accounting Standards will
be followed for accounting Income and Expenditure of the CMTS Segment. Basic
accounting records and trial balances will be prepared at all cost and revenue centers.
Thus the following units will be maintaining accounts and preparing Trial Balances on a
monthly basis. These accounts will be compiled periodically for preparation of
company‘s financial statements, as per statutes.
 AO CMTS
 AO Cash
14.2 Separate and independent Collection and Operation Accounts have to be
maintained by AO Cash and AO CMTS, for the CMTS operations. For accounting
purpose CMTS will be treated as a separate segment.
7.22 OTHER REPORTS
Circles shall make available the information of mobile services, by due dates, as
may be needed by corporate office in the format prescribed.
7.23 BSNL SALES STRUCTURE AND CHANNELS

Initially BSNL did not have a well-defined exclusive sales structure. The concept
of commercial officer, CSCs and Marketing agents was expanded by introduction of
franchisees with the launch of BSNL mobile services in October 2002. Since then, a
strong need was felt to strengthen sales channels in BSNL and also to create sales role
specific job structure in BSNL. In October 2009, as part of Project Shikhar, a new sales
setup has been designed. Consumer mobility and Consumer Fixed Access verticals have
dedicated GM/DGM rank officers at Corporate as well as Circle level to plan, manage
and effect retail sales. The following are sales channels of BSNL:
7.23.1 FRANCHISEES:
BSNL has put in place Franchisee Sales & Distribution policy 2009.A
comprehensive Sales & Distribution Policy is also being worked out. Franchisees are
appointed through EOI route by respective SSAs. Salient features of this scheme are:
• Well defined geographical area for franchisee called as primary area
• Exclusive franchisee showroom as per design specified by BSNL
• Franchisees to appoint Feet on Street (FoS)
• Franchisee shop to open 0800h to 2200h
• Financial penalty for not meeting cut off performance score

• Franchisee can appoint any number of sub franchisees/retailers on nonexclusive

basis.
Franchisees play a very important role in serving customers across the country and
improve BSNL visibility. BSNL is yet to build the reach comparable to competitors. In
order to motivate franchisees, time to time reward scheme are introduced.
7.23.2 DIRECT SELLING AGENTS (DSA’S):

Any 10th pass can become a DSA. Retired BSNL employees/spouses can also
become DSAs. The OBJECTIVES is to sell BSNL services door to door extending
ultimate convenience to BSNL customers. Any number of DSAs can be appointed by
SSA Heads.
7.23.3 ANY OTHER RETAIL OUTLETS:
Any other outlets such as shopping malls, post offices etc. can also be appointed
as DSA to sell BSNL services with the approval of concerned CGM. BSNL has also
allowed to appoint Service Centre Agents (SCA) of Common Service Centres (CSC) of
Department of Information Technology being setup in rural areas across the country as
DSAs. DIT is setting up 1,12,000 CSCs and is expected to strengthen BSNL‘s reach.
7.23.4 EPIN FRANCHISEES:
BSNL has also appointed EPIN franchisees across the country. All recharge
vouchers, sancharnet card, VCC card etc. have a secret PIN for use of respective service.
These PINs are sold in bulk to appointed franchisees. Any Indian Registered company /
Registered Cooperative Society / Registered NGO fulfilling prescribed criteria can
become Circle level or All India level franchisee. For Circle level franchisees, the
commission structure depends on the type of agreement i.e. exclusive or non-exclusive.
All India franchisees are appointed on non-exclusive basis. These franchisees can sell
these PINs through point of sales terminal or through PC connected to main server of
franchisee.
7.23.5 BUSINESS ASSOCIATES (BA’S):
These are now handled by Enterprise Business/Business Development units. Their
primary job is to sell Data services but they are allowed to sell complete range of BSNL
services to act as single window Total telecom Solution provider to enterprise customers.
7.23.6 WEB SELF CARE (WSC):
Sales are possible through link provided on BSNL website www.bsnl.co.in . VCC
card, Call Now, FLPP and mobile recharge vouchers can be purchased with the help of
Internet banking account of certain banks such as ABN, AXIS, BoB, BoI, BoP, IDBI,
PNB, SBI, UBI etc.
7.23.7 SALES TEAMS:
Heads of SSA have to appoint a suitable BSNL executive preferable CSC
incharge to act as single window interface for the franchisees. Nodal officer is required to
maintain inventory, stock register and reconcile revenue and sales made by franchisees.
Minimum three months inventory has to be stocked by SSAs. In October 2008, BSNL
decided to appoint sales staff in each SSA.Each circle has been asked to appoint 250-300
sales teams. Each team comprises of 4-6 Telephone mechanics, TOAs lead by
JTO/SDE/Sr SDE rank officer. 4-6 such teams have to report to an officer of AGM rank
who has to be allocated specific sales targets by SSA Head. Existing line staff accepting

sales duty is being designated as Retailer Manager. Special teams are being appointed
under Project Udaan and Project Vijay. Very lucrative reimbursement schemes have been
put in place. For example under Project Vijay, travel & meal allowance varying from Rs
1300-Rs 2600 is allowed to sales team member depending on their quantum of work.
Similarly for Udaan sales team leader & sales associates Rs 1400/- per month is allowed
towards meal & travel expenses.
Sales software in CRM module of CDR project: As part of BSNL
CDR/Convergent billing project under commissioning, a centralized CRM module having
sales features is also being put in place for handling all BSNL service as a single window
concept. Functions like lead generation, lead qualification, selling to a retail new/existing
customer will be available.
7.24 SANCHARSOFT?
Sancharsoft is a web application created for the management of SIM, Recharge
Coupons & Top up Cards of Mobile Services of BSNL.
 It is an Inventory Management Package.
 Management Reports are hosted on intranet.bsnl.co.in.
7.24.1 SANCHARSOFT: TECHNICAL DETAILS
It is a web based package created on MS IIS platform using asp (MS Active
server pages technology & Javascript). All the CSR clients can access to the web service
and can login using their username & password. All Dealers, DSA‘s and Retailers can
use the service via secure network when extended to them.
7.24.2 OBJECTIVES OF SANCHARSOFT
Sancharsoft is a tool for Management of
 CMTS Sales and Distribution Network.
 Franchises and Retailers performance Monitoring. • DSA and BSNL
Shoppe Performance Monitoring.
 Other Channel Partners like BPCL, Handset Vendors.
 Franchise and Retailers Database Management and Reporting.
 Payment of Commission.
 Reconciliation of Recharge Vouchers with revenue realized.
 Reconciliation of CTOPUP revenue realized v/s CTOPUP carried out.
 Monitoring of Inventory levels with Franchisee, Retailers and DSA/PCOs.
7.24.3 CAPABILITIES OF SANCHARSOFT.
 Sales and Distribution.
 Auto Activation, deactivation and swapping of prepaid cards.
 Recharge voucher enabling, Damaged card blocking.
 Franchisee, Retailer and Other channels Performance Monitoring.
7.24.4 LIMITATION OF SANCHARSOFT

 Accounting- it is an inventory package to facilitate the invoice.
 Real time utilization of Infrastructure details like equipped capacity etc.
Can‘t handle other products like Landline, Broadband.
7.24.5 THREE KEY MODULES OF SANCHARSOFT.
SIM Module


(Activations, CAF-Customer Application Form) SIM Allotment upto POS
(Point Of Sale) and Retailer Network.
 Invoice Generation.
 SIM Activation.
 CAF Monitoring, CAF Information Storage and retrieval.
 Dynamic Stock and Sale Report.
Recharge Module
 Opening Balance Coupon Loading (one time only during Change Over) •
Ease of Distribution and Sales.
 Expiry / missing cards blocking.
C-TOP Module.
 CTOP UP Sales from nearest CSC.
 Cash receipt/revenue reports.
 Sales Reconciliation.
 Performance Monitoring.
 Balance and status of any CTOP number to Franchises / CSC / FMT /
RMC. FMT-Franchisee Manager Team, RMC- Retailer Manager
Coordinator) curator
7.24.6 BENEFITS OF SANCHARSOFT.
1. SIM Module
 (Activations, CAF-Customer Application Form)
 At a glance report of BSNL S&D (Sales and Distribution).
 CAF and SIM Tracking.
 Available cards stock with Retailers / Franchisees.
 Commission and Retention bonus reports.
 Direct activation by retailer possible.
 CAF submission due, Retailer Activation Report, CAF Collection from
retailer by courier can be implemented.
2. Recharge Module.
 Ease of Sales and Distribution down the line to Franchisee and
 Retailers.
 Auto Voucher enabling, blocking etc.
 Franchisee / Retailers Target monitoring.
 Easier and Faster replacement of damaged cards.
3. C-TOP Module.
 Sales Report and Balance Report of Franchisee to FMT.
 Sales and Balance Report of Retailers to Franchisee.
 Overall performance of Franchisee including CTOP sales / Voucher sales.
 Easier Access to CTOP – i.e. Sales form CSC instead of SSA HQ.
 Direct SIM commission remittance to CTOP number – for Franchisee /
Retailer.
7.24.7 SANCHARSOFT MENU
The various menus used for Prepaid, Recharge / Topup cards are:
 Home
 Prepaid
 Recharge

 Replacement
 Stock
 Re-printing
 Reports
 Query
 Dealer sales
7.24.8 SANCHARSOFT EXAMPLE WINDOW
Figure 67: Sancharsoft

Prepaid Menu
 Normal
 Prepaid by choice
 Discount sale.
Recharge Menu
 Coupons
 CTOPUP Standard
 CTOPUP Flexi
 Delete Uploaded.
 Coupon Blocking
 Offline sales.
Replacement Menu
 SIM Cards
 Replacement – Recharge / Top-Up coupons
 Stock Menu
 Stock return
 Stock Diversion
 Stock indent
 Reprinting
 Prepaid
 Replacement
 CTOPUP recharge
 PCO/DSA invoice

 Stock return
Reports
 Daily statement
 Consolidated sales
 Stock
7.25 CONCLUSION
Billing and sanchsoft are important tool for Sales and Distribution.

E3-E4 Consumer Mobility 3G Mobile Network
8 3G MOBILE NETWORK
8.1 LEARNING OBJECTIVES:
After completion of this chapter student will able to understand:
 The Universal Mobile Communication Services (UMTS) and its
benefits over the 2G mobile Communication
 Technologies used in UMTS
 Wideband Code Division Multiple Access technology
 WCDMA Radio network system architecture.
 UMTS core network elements
 Various domains in 3G Core Network
8.2 INTRODUCTION
UMTS is the convergence of mobile communications, Information Technology
(IT) and multimedia technologies. The benefit of UMTS is richer, more powerful
communication. UMTS is a collection of radio and network technologies that provide:
 better spectrum efficiency,
 high data transmission rates (up to 2 Mbit/s),
 worldwide roaming capability,
 the capability to offer new multimedia applications and services,
 interoperability with both fixed and mobile telecommunications
services.
UMTS is the natural evolution from GSM and other second generation (2G)
mobile systems. It provides interconnection with 2G networks as well as other terrestrial
and satellite-based networks.
8.3 UMTS STANDARD
UMTS is an International Mobile Telecommunications - 2000 (IMT-2000) 3G
system. The other main IMT–2000 system proposed by the ITU is CDMA 2000.
Figure 68: 3G Standardization Environment

8.4 Overview of UMTS release architectures
This section provides a general description of the current standard UMTS release
architectures. UMTS architectures provide a smooth transition from second generation
telecommunications systems by slowly phasing in new software and new network
elements.

a) 3GPP currently defines standards for the following UMTS releases

b) 3GPP Release 99 (R99),
c) 3GPP Release 4 (Next Generation Network (NGN) architecture),
d) 3GPP Release 5 (all-IP core network).
Note : Release 2000 (R00) is split into ―Release 4‖ and ―Release 5‖.
Figure 69: Summary of 3GPP network architectures

8.5 3GPP Release 99 (R99)
3GPP Release 99 (R99) includes the following network elements:
a) Radio Access Networks
b) Base Station Subsystem (BSS) for access to GSM services which includes:
c) Base Transceiver Stations (BTS),
d) Base Station Controller (BSC).
Universal Terrestrial Radio Access Network (UTRAN) for access to UMTS services and
including:
 Node Bs,
 Radio Network Controller (RNC).
8.5.1 CORE NETWORK:
Circuit-Switched Core Network (CSCN) includes elements that support circuit
switched connections. Circuit-switched connections are connections where the operator
has full and exclusive use of the circuit until the connection is released. CSCN elements
for R99 include:
a) Mobile services Switching Center (MSC),
The MSC is the interface between the Radio Access Network (RAN) and fixed
networks. It provides mobility management, call control and switching functions to
enable circuit-switched services to and from mobile stations.
b) Gateway Mobile services Switching Center (GMSC),
The GMSC interfaces with the fixed networks, handles subscriber location
information from the HLR and performs routing functions to and from mobile
stations. GMSC functionality can be contained in all or some of the MSCs of the
network, depending on network configuration.
c) InterWorking Function (IWF),
The IWF provides interworking functionality between a Public Land Mobile Network
(PLMN) and fixed networks (such as ISDN, PSTN and PDN). The IWF converts
protocols used in the PLMN to those used in the corresponding fixed network.

8.5.2 PACKET-SWITCHED CORE NETWORK (PSCN)

PSCN includes elements that support packet switching technology. Packet-
switching technology routes packets of user data independently of one another. No
dedicated circuit is established. Each packet can be sent along different circuits depending
on the network resources available. PSCN elements for R99 include:
a) Serving GPRS Support Node (SGSN),
The SGSN and the GGSN are the interface elements between the RAN and fixed
networks. The SGSN provides mobilitiy management, session management and
transfer and routing functions to enable the transfer of packet-switched data services.
b) Gateway GPRS Support Node (GGSN),
The GGSN handles subscriber location information and provides packet data transfer
capabilities to and from mobile terminals.
c) Border Gateway (BG),
The BG provides connectivity, and interworking and roaming capabilities between
two different PLMNs. Common Core Network elements are elements used by both
the CSCN and PSCN.
Common elements for R99 include:
a) Home Location Register (HLR),
The HLR is the permanent database for mobile subscriber information. The HLR is in
charge of mobile subscriber management.
b) Visitor Location Register (VLR),
The VLR manages mobile subscribers in the home PLMN and those roaming in a
foreign PLMN. The VLR exchanges information with the HLR.
c) Authentication Center (AuC),
The AuC provides authentication and encryption functions for system security
d) Equipment Identity Register (EIR),
The EIR stores information on mobile equipment identities.
e) SMS MSCs.
SMS MSCs enable the transfer of messages between the Short Message Service
Center and the PLMN.
Figure below gives an illustration of 3GPP Release 99 network architecture.
Figure 70: 3GPP Release 99 architecture


3GPP Release 4 implements the NGN architecture in the core network, separating
the control and user planes. This enables a true separation of control and connection
operations, and provides the independence of applications and services from basic
switching and transport technologies. 3GPP Release 4 (R4) introduces the following new
network elements in addition to R99 elements:
8.6.1 CORE NETWORK IN R4
Circuit Switched Core Network
a) MSC server
The MSC server provides call control and mobility management functions for an
MSC. It also holds subscriber service data information and provides connection
control for media channels in a CS-MGW.
GMSC server
The GMSC server provides call control and mobility management functions for a
GMSC.
b) Circuit-Switched-Media Gateway (CS-MGW)
The CS-MGW is an interface between the UTRAN and the Core Network. The CS-
MGW supports both UMTS and GSM media. CS-MGW terminates bearer channels
from circuit-switched networks and media streams from packet networks. It supports
media conversion, bearer control and payload processing. The figure below gives an
illustration of 3GPP Release 4 network architecture.


3GPP Release 5 implements a unified IP backbone infrastructure which enables
high performance services and functions. 3GPP Release 5 (R5) introduces the following
new network elements in addition to R99 and R4 elements:
8.7.1 CORE NETWORKIN R5
Common Core Network elements:
 Home Subscriber Server (HSS),
 Internet protocol Multimedia (IM) subsystem.
The IM subsystem consists of all Core Network elements that use the services
provided by the PSCN to offer multimedia services. The IM subsystem primarily includes
the Call Server Control Function (CSCF), Media Gateway Control Function (MGCF) and
the Multimedia Resource Function (MRF).
The following figure gives an illustration of 3GPP Release 5.

8.8 UMTS technology
The main technological difference between 2G and 3G systems is the new
multiple access technique in the Radio Access Network (RAN) that increases bandwidth

and efficiency. This technology is called Code Division Multiple Access (CDMA). 3G
standards organizations have selected three CDMA radio interface technologies for 3G
networks:
a) WCDMA which uses Frequency Duplex Division (FDD) mode,
b) TD-CDMA which uses Time Division Duplex (TDD) mode,
c) CDMA 2000 which is seen as the natural evolution for operators with
existing IS-95 networks.
8.9 WCDMA – A DEVELOPMENT FROM GSM AND CDMA

There has been a tremendous growth in wireless communication technology over
the past decade. The significant increase in subscribers and traffic, new bandwidth
consuming applications such as gaming, music down loading and video streaming will
place new demands on capacity. The answer to the capacity demand is the provision of
new spectrum and the development of a new technology – Wideband CDMA or
hereinafter referred to as WCDMA.
Naturally, there are a lot of differences between WCDMA and GSM systems, but
there are many similarities as well. The GSM Base Station Subsystem (BSS) and the
WCDMA Radio Access Network (RAN) are both connected to the GSM core network for
providing a radio connection to the handset. Hence, the technologies can share the same
core network. Furthermore, both GSM BSS and WCDMA RAN systems are based on the
principles of a cellular radio system. The GSM Base Station Controller (BSC)
corresponds to the WCDMA Radio Network Controller (RNC). The GSM Radio Base
Station (RBS) corresponds to the WCDMA RBS, and the A-interface of GSM was the
basis of the development of the Iu-interface of WCDMA, which mainly differs in the
inclusion of the new services offered by WCDMA. The significant differences, apart from
the lack of interface between the GSM BSCs and an insufficiently specified GSM Abis-
interface to provide multi-vendor operability, are more of a systemic matter. The GSM
system uses TDMA (Time Division Multiple Access) technology with a lot of radio
functionality based on managing the timeslots. The WCDMA system on the other hand
uses CDMA which means that both the hardware and the control functions are different.
Examples of WCDMA-specific functions are fast power control and soft handover.
8.9.1 CODE DIVISION MULTIPLE ACCESS AND WCDMA

Code Division Multiple Access (CDMA) is a multiple access technology where
the users are separated by unique codes, which means that all users can use the same
frequency and transmit at the same time. WCDMA is a step further in the CDMA
technology. It uses a 5 MHz wide radio signal and a chip rate of 3.84 Mcps, which is
about three times higher than the chip rate of CDMA2000 (1.22 Mcps).
The main benefits of a wideband carrier with a higher chiprate are:

a) Support for higher bit rates
b) Higher spectrum efficiency thanks to improved trunking efficiency (i.e. a better
statistical averaging)
c) Higher QoS
8.9.2 RADIO NETWORK FUNCTIONALITY

For optimal operation of a complete wireless system i.e. from handset to radio
access network (RAN) several functions are needed to control the radio network and the

many handsets using it. All functions described in this section, except for Handover to
GSM, are essential and therefore necessary for a WCDMA system.
8.9.3 POWER CONTROL
The power control regulates the transmit power of the terminal and base station,
which results in less interference and allows more users on the same carrier. Transmit
power regulation thus provides more capacity in the network. With a frequency re-use of
1, it is very important to have efficient power control in order to keep the interference at a
minimum. For each subscriber service the aim is that the base station shall receive the
same power level from all handsets in the cell regardless of distance from the base station.
If the power level from one handset is higher than needed, the quality will be excessive,
taking a disproportionate share of the resources and generating unnecessary interference
with the other subscribers in the network. On the other hand, if power levels are too low
this will result in poor quality. In order to keep the received power at a suitable level,
WCDMA has a fast power control that updates power levels 1500 times every second. By
doing that, the rapid change in the radio channel is handled. To ensure good performance,
power control is implemented in both the up-link and the down-link, which means that
both the output powers of the handset and the base station are frequently updated.
Power control also gives rise to a phenomenon called ―cell breathing‖. This is the
trade-off between coverage and capacity, which means that the size of the cell varies
depending on the traffic load. When the number of subscribers in the cell is low (low
load), good quality can be achieved even at a long distance from the base station. On the
other hand, when the number of users in the cell is high, the large number of subscribers
generates a high interference level and subscribers have to get closer to the base station to
achieve good quality.

Figure 74: Cell Breathing
8.9.4 SOFT AND SOFTER HANDOVER

With soft handover functionality the handset can communicate simultaneously
with two or more cells in two or more base stations. This flexibility in keeping the
connection open to more than one base station results in fewer lost calls, which is very
important to the operator. To achieve good system performance with a frequency re-use
of 1 and power control, soft and softer handover is required. Soft and softer handover
enables the handset to maintain the continuity and quality of the connection while moving
from one cell to another. During soft or softer handover, the handset will momentarily
adjust its power to the base station that requires the smallest amount of transmit power
and the preferred cell may change very rapidly. The difference between soft and softer
handover is that during soft handover, the handset is connected to multiple cells at
different base stations, while during softer handover, the handset is connected to multiple
cells at the same base station.
Figure 75: Soft Handoff
8.9.5 HANDOVER TO GSM (INTER-SYSTEM HANDOVER)

When WCDMA was standardized a key aspect was to ensure that existing
investments could be re-used as much as possible. One example is handover between the
new (WCDMA) network and the existing (GSM) network, which can be triggered by
coverage, capacity or service requirements. When a subscriber moves out of the

WCDMA coverage area, a handover to GSM has to be conducted in order to keep the
connection. Handover between GSM and WCDMA can also have a positive effect on
capacity through the possibility of load sharing. If, for example, the numbers of
subscribers in the GSM network is close to the capacity limit in one area, handover of
some subscribers to the WCDMA network can be performed. Another function that is
related to inter-system handover is the compressed mode. When performing handover to
GSM, measurements have to be made in order to identify the GSM cell to which the
handover will be made. The compressed mode is used to create the measurement periods
for the handset to make the required measurements. This is typically achieved by
transmitting all the information during the first 5 milliseconds of the frame with the
remaining 5 milliseconds being used for measurements on the other systems.
Figure 76: Inter-frequency handover (intra-system handover)

The need for inter-frequency handover occurs in high capacity areas where
multiple 5 MHz WCDMA carriers are deployed. Inter-frequency handover, which is
handover between WCDMA carriers on different frequencies, has many similarities with
GSM handover, for example the compressed mode functionality.
8.9.6 CHANNEL TYPE SWITCHING

In WCDMA there are different types of channels that can be used to carry data in
order to maximize the total traffic throughput. The two most basic ones are common
channels and dedicated channels. Channel type switching functionality is used to move
subscribers between the common and the dedicated channel, depending on how much
information the subscriber needs to transmit. The dedicated channel is used when there is
much information to transmit, such as a voice conversation or downloading a web page. It
utilizes the radio resources efficiently as it supports both power control and soft handover.
The common channel, on the other hand, is less spectrum efficient. One benefit is that the
common channel reduces delays as many subscribers can share the same resource. Hence
it is the preferred channel for the transfer of very limited information.
8.9.7 ADMISSION CONTROL

As there is a very clear trade-off between coverage and capacity in WCDMA
systems, the admission control functionality is used to avoid system overload and to
provide the planned coverage. When a new subscriber seeks access to the network,
admission control estimates the network load and based on the new expected load, the

subscriber is either admitted or blocked out. By this the operator can maximize the
network usage within a set of network quality levels, i.e. levels depending on what kind
of service/information the subscriber wants to use.
8.9.8 CONGESTION CONTROL

Even though an efficient admission control is used, overload may still occur,
which is mainly caused by subscribers moving from one area to another area. If overload
occurs, four different actions can be taken. First, congestion control is activated and
reduces the bit rate of non real-time applications, to resolve the overload. Second, if the
reduced bit rate activity is not sufficient, the congestion control triggers the inter- or intra-
frequency handover, which moves some subscribers to less loaded frequencies. Third,
handover of some subscribers to GSM and forth action is to discontinue connections, and
thus protect the quality of the remaining connections.
8.9.9 SYNCHRONIZATION
One of the basic requirements when WCDMA was standardized was to avoid
dependence on external systems for accurate synchronization of base stations. This has
been achieved by a mechanism, where the handset, when needed, measures the
synchronization offset between the cells and reports this to the network. In addition, there
is also an option to use an external source, such as GPS, for synchronizing the nodes, i.e.
to always provide the best solution both asynchronous and synchronous nodes are
supported/
8.10 BASIC ARCHITECTURE CONCEPTS OF WCDMA RADIO

SYSTEM
In this section some fundamental views of the WCDMA Radio Access Network
will be presented. This includes the WCDMA RAN architecture itself, the radio interface
protocol architecture, the Radio Access Bearer concept and the role of the transport
network in a WCDMA RAN.
8.10.1 RADIO ACCESS NETWORK (RAN) ARCHITECTURE

The main purpose of the WCDMA Radio Access Network is to provide a
connection between the handset and the core network and to isolate all the radio issues
from the core network. The advantage is one core network supporting multiple access
technologies. The WCDMA Radio Access Network consists of two types of nodes:
The Radio Base Station handles the radio transmission and reception to/from the
handset over the radio interface (Uu). It is controlled from the Radio Network Controller
via the Iub interface. One Radio Base Station can handle one or more cells.
8.10.2 RADIO NETWORK CONTROLLER (RNC)
The Radio Network Controller is the node that controls all WCDMA Radio
Access Network functions. It connects the WCDMA Radio Access Network to the core
network via the Iu interface. There are two distinct roles for the RNC, to serve and to
control. The Serving RNC has overall control of the handset that is connected to
WCDMA Radio Access Network. It controls the connection on the Iu interface for the
handset and it terminates several protocols in the contact between the handset and the
WCDMA Radio Access Network. The Controlling RNC has the overall control of a
particular set of cells, and their associated base stations.

When a handset must use resources in a cell not controlled by its Serving RNC,
the Serving RNC must ask the Controlling RNC for those resources. This request is made
via the Iur interface, which connects the RNCs with each other. In this case, the
Controlling RNC is also said to be a Drift RNC for this particular handset. This kind of
operation is primarily needed to be able to provide soft handover throughout the network.
8.10.3 RADIO ACCESS BEARERS

The main service offered by WCDMA RAN is the Radio Access Bearer (RAB).
To establish a call connection between the handset and the base station a RAB is needed.
Its characteristics are different depending on what kind of service/information to be
transported. The RAB carries the subscriber data between the handset and the core
network. It is composed of one or more Radio Access Bearers between the handset and
the Serving RNC, and one Iu bearer between the Serving RNC and the core network.
3GPP has defined four different quality classes of Radio Access Bearers:
 Conversational (used for e.g. voice telephony) – low delay, strict ordering
 Streaming (used for e.g. watching a video clip) – moderate delay, strict
ordering
 Interactive (used for e.g. web surfing) – moderate delay
 Background (used for e.g. file transfer) – no delay requirement
Figure 77: 3G Architecture

Both the Conversational and Streaming RABs require a certain reservation of
resources in the network, and are primarily meant for real-time services. They differ
mainly in that the Streaming RAB tolerates a higher delay, appropriate for one-way real-
time services.
The Interactive and Background RABs are so called ‗best effort‘, i.e. no resources
are reserved and the throughput depends on the load in the cell. The only difference is
that the Interactive RAB provides a priority mechanism. The RAB is characterized by
certain Quality of Service (QoS) parameters, such as bit rate and delay. The core network

will select a RAB with appropriate QoS based on the service request from the subscriber,
and ask the RNC to provide such a RAB.
8.11 UMTS Core Network

The Universal Mobile Telecommunication System (UMTS) Core Network (CN)
can be seen as the basic platform for all communication services provided to UMTS
subscribers. The basic communication services include switching of circuit-switched calls
and routing of packet data. The 3G Partnership Project (3GPP) also introduces a new
subsystem called the ‗‗IP Multimedia Subsystem‘‘ (IMS). The IMS opens up the Internet
Protocol (IP)-based service world for mobile use by seamlessly integrating the mobile
world and the Internet world and providing sophisticated service mechanisms to be used
in the context of mobile communications. The CN maps end-to-end Quality of Service
(QoS) requirements to the UMTS bearer service. When inter-connecting with other
networks, QoS requirements also need to be mapped onto the available external bearer
service. The gateway role of the UMTS CN in creating an end-to-end service path is
illustrated in Figure. The external bearer does not fall within the scope of UMTS system
specifications and this may create some local problems if the QoS requirements to be
satisfied between the UMTS and external network do not match.
Between the Mobile Termination (MT) and the CN the QoS is provided by the
radio access bearer. The radio access bearer hides QoS handling over the radio path from
the CN. Within the CN, QoS requirements are mapped to its own bearer service, which in
turn is carried by backbone bearers on top of the underlying physical bearer service. A
challenge to CN implementation is that the operator is pretty much free to choose how to
implement physical backbone bearers. These bearers rely on the physical transmission
technologies used between CN nodes. Typical transmission technologies, like PDH and
SDH, with Pulse Code Modulation (PCM) channeling or with Asynchronous Transfer
Mode (ATM) cell-switching are used. In 3GPP R5 the emphasis is on replacing these
technologies by the Internet Protocol (IP) wherever and whenever possible, since making
this transport network uniform simplifies the functionality of higher protocol layers.
The UMTS represents a kind of philosophy for use in production of a universal
core that is able to handle a wide set of different radio accesses. Looking back at the
network evolution, we see there are three types of recognised radio accesses as far as
3GPP R5 is concerned: WCDMA/HSDPA, GSM/EDGE and, possibly, complementary
access. Of these, WCDMA/HSPDA and GSM/EDGE are implemented, while
complementary access is under study. The core part of the UMTS network does not
evolve in as straightforward a way as the radio network due to both the CN‘s traditional
infrastructure basis and its advanced technologies, which may have a number of different
impacts on the evolution of the core part of the UMTS.
The following figure shows the conceptual nature of the UMTS CN: the radio
accesses drawn as continuous lines are the ones used at the outset and the others are
regarded as access candidates as time goes by.

Figure 78: 3G Core Network
8.11.1 UMTS CORE NETWORK ARCHITECTURE

3GPP R99 introduced new mechanisms and capacity increases for the access
network side. Starting with 3GPP R4 and its actual realisation in 3GPP R5 the CN has
undergone major changes. In this chapter we will introduce, albeit briefly, the main
characteristics of 3GPP R5. As shown in Figure the UMTS CN consists of equipment
entities called ‗‗domains‘‘ and ‗‗subsystems‘‘ whose purpose is to describe the traffic
characteristics the equipment takes care of. Based on this division, the UMTS CN
contains the following entities:
a) Circuit Switched (CS) domain.
b) Packet Switched (PS) domain.
c) IP Multimedia Subsystem (IMS).
d) BroadCast (BC) domain.

Figure 79: Core Network Structure

The difference between a domain and a subsystem as far as the CN is concerned is
as follows:
The CN domain is an entity directly interfacing one or more access networks. This
interface is called ‗‗Iu‘‘. Due to the nature of traffic and to identify the domain, the Iu is
very often subscripted: for example, IuCS is the interface between an access network and
the CS domain and delivers CS traffic; IuPS is the interface for PS traffic purposes; and
IuBC is the interface that carries a broadcast/multicast type of traffic. CN subsystems do
not have a direct Iu-type interface with access networks. Instead, they utilise other,
separately defined interfaces to connect themselves to one or more CN domains. Figure is
not exhaustive but aims to illustrate the most important interfaces within the UMTS CN.
In this figure, the bold lines indicate user traffic (user plane) and thinner lines
indicate signaling connections (control plane). As far as the CN is concerned, there are
some items that need to be pointed out:
The connections drawn in the figure represent logical, direct connections. In
reality, however, the connections have other ways of connecting due to transport network
solutions.
The CS Media Gateway (CS-MGW) and the Gateway Mobile Services Switching
(GMSC) server can be combined into one physical entity. In this case the entity is simply
called the ‗‗GMSC‘‘. If the CS domain structure follows 3GPP R99, the CS-MGW and
MSC Server could be combined into one physical entity. In this case the entity is called
the MSC/VLR (Visitor Location Register).
If the Serving GPRS Support Node (SGSN) and MSC/VLR are combined into
one physical entity it is called the UMSC (UMTS MSC).

Figure 80: Core Network Entities that Are Common to All

Domains and Subsystems
In addition to domains the CN contains some functionalities that are common to
all CN domains and subsystems. These common functionalities are mainly collected in an
entity called the ‗‗Home Subscriber Server‘‘ (HSS).
In the 3GPP R5 architecture, the HLR and AuC are considered HSS subsets, but
they still provide the same functionalities
Figure 81: Logical Diagram about HSS functionalities and interfaces to

CN domains
In addition to the HSS, the Equipment Identity Register (EIR) is a functionality
common to all domains and subsystems. The EIR stores information about end-user
equipment and the status of this equipment. To do this, it makes use of three ‗‗lists‘‘: put
roughly, the white list contains information about approved, normal terminal equipment;

the black list stores information about stolen equipment; and the grey list contains serial
number information about suspect equipment. Of these lists, the black and grey ones are
normally implemented—it is unusual for the white list to be used. The EIR maintains
these lists and provides information about user equipment to the CN Domain on request.
If the EIR indicates that the terminal equipment is blacklisted, the CN domain refuses to
deliver traffic to and from that terminal. In case the terminal equipment is on the grey list,
the traffic will be delivered but some trace activity reporting may occur.
8.11.2 CS DOMAIN
The aim of CS-MGW–MSC server division is to separate the control and user
plane from each other within the CS domain. This introduces scalability to the system,
since a single MSC server could control many CS-MGWs. Another advantage of this
distributed CS domain architecture is that it opens up the possibilities for user plane
geographical optimisation. For instance, an operator could locate CS-MGWs freely within
its network and, by proper routing arrangements, it will be possible to arrange things in
such a way that the user plane goes through the network geographically in the shortest
possible way. The CS-MGW may also contain various conversion packages, which would
give the operator the possibility of considering optimised transport network arrangements.
For example, using the CS-MGW concept the operator could convert the CS domain
backbone to use IP instead of other transport network mechanisms between the access
network edge CS-MGW and the legacy Public Switched Telephone Network (PSTN)
edge gateway.
Figure 82: UMTS CN CS
The 3GPP-R4-distributed CS domain architecture defines MSC division, where

call control functionality and the VLR are brought into an entity called the ‗‗MSC
server‘‘. Respectively, user plane connectivity and related items (e.g., network inter-
working) are brought into an entity called the ‗‗Media Gateway‘‘ (MGW). The CN as a
whole contains all kinds of gateways and, thus, it is recommended to add the lettering
‗‗CS‘‘ in front of MGW to make it crystal clear that we are speaking about the Circuit
Switched domain Media Gateway (CS-MGW).
8.11.3 PS DOMAIN
The two main elements of the PS domain are types of mobile network-specific
servers are Serving GPRS Support Node (SGSN) and Gateway GPRS Support Node

(GGSN). SGSN contains the location registration function, which maintains data needed
for originating and terminating packet data transfer. These data are subscription
information containing the International Mobile Subscriber Identity , various temporary
identities, location information, Packet Data Protocol (PDP) addresses (de facto but not
necessarily IP addresses), subscripted QoS and so on.
The tool for data transfer within the PS domain is called the ‗‗PDP context‘. In
order to transfer data, the SGSN must know with which GGSN the active PDP context of
a certain end-user exists. It is for this purpose that the SGSN stores the GGSN address for
each active PDP context. Note that one SGSN may have active PDP contexts going
through numerous GGSNs.
Figure 83: PS Domain Structure

The GGSN also holds some data about the subscriber. These data may also
contain the IMSI number, PDP addresses, location information and information about the
SGSN that the subscriber has registered. As far as the PS domain architecture is
concerned, the SGSN and GGSN as such are insufficient. Packet traffic require additional
elements/functionalities for addressing, security and charging. Figure aims to illustrate
the most relevant functionalities within the PS domain.
For security reasons operators now use dynamic address allocation for end-users.
These addresses can be allocated in many ways, but the normal way to do this is to use
Dynamic Host Configuration Protocol (DHCP) functionality/server. Depending on the
operator‘s configuration, the DHCP allocates either IPv4 or IPv6 addresses forthe end-
user‘s terminal equipment.
Actually, the PS domain is, in a way, a sophisticated intranet. In order to address
the various elements within this intranet, the Domain Name Server (DNS) is needed. The
DNS within the PS domain is responsible for addressing PS domain elements. For
example, when an SGSN establishes traffic to a certain GGSN, the SGSN requests the
required GGSN address from the DNS.
When a user has gained a dynamically allocated address and the connection has
been established between the SGSN and GGSN, the user is ready to access services that
are made accessible by the operator. Service access is arranged through Access Point
Names (APNs) which can be freely defined but very often are service-specific. For
instance, one APN could be the ‗‗Internet‘‘ and through this APN the user is able to start
Internet-browsing. Another APN could be, say, the ‗‗WAP‘‘ and this APN leads the end-
user to browse WAP menus made available by the operator. One GGSN may contain tens
of thousands of APN definitions: they could be company/corporate specific, they could

lead to any place, any network, etc. If the operator does not want to have this kind of
access control, a so-called ‗‗wild card‘‘ APN can be brought into use. In this case end-
user preferences as such are allowed and the operator just provides the connection.
Since security is an issue, the GGSN has a FireWall (FW) facility integrated.
Every connection to and from the PS domain is done through the FW in order to
guarantee security for end-user traffic.
There are many networks that contain a PS domain and roaming between these
networks is a most vital issue as far as business is concerned. The PS domain contains a
separate functionality in order to enable roaming and to make an interconnection between
two PS domains belonging to separate networks. This functionality is called the ‗‗Border
Gateway‘‘ (BG). GPRS Roaming Exchange (GRX) is a concept designed and
implemented for General Packet Radio Service (GPRS) roaming purposes. For charging
data collection purposes the PS domain contains a separate functionality called the
‗‗Charging Gateway‘‘ (CGW). The CGW collects charging data from PS domain
elements and relays them to the billing centre to be post-processed. Charging is also the
main factor behind some GRX roaming arrangements. A very typical way of doing this is
when a user is visiting a GPRS-capable network: the GGSN for GPRS connection is
arranged from the home network of the user. By doing this the home network operator is
in a position to collect charging data related to this GPRS connection.
This arrangement also relinquishes control about APNs to the home network
operator. Referring to the APN explanation above, this ‗‗home network GGSN‘‘
arrangement does not allow wild card APNs. If a visited network GGSN was used during
roaming, wild card APNs are allowed, respectively.
As Figure states, the PS domain maintains various connections. First, it maintains
the IuPS interface towards access networks. Through this interface UTRAN and GERAN
are connected. When GERAN is connected to the network in this way, it is said that the
network uses GERAN Iu mode. There is still a possibility to use a framerelay- based Gb
interface for GERAN connection. In this case it is said that the network uses GERAN Gb
mode. UTRAN is restricted to using the Iu interface for PS domain connections. Possible
complementary accesses and their interconnection mechanisms are under study.
Second, the PS domain has a connection to CN common functionalities, like HSS
and EIR. Through these connections the PS domain handles information related to the
tasks.The PS domain is the network platform for sophisticated multimedia
services enabled and maintained by the IMS. Thus, the PS domain contains interfaces
towards the IMS.
8.12 CONCLUSION
WCDMA is very successful technology due to its robust radio network design. By
virtue of WCDMA and frequency reuse the capacity and of WCDMA system is increased
tremendously. But with the introduction of Data on mobile WCDMA has lost its shine as
it deliveries very less data rates. Thus WCDMA has been migrated to newer technologies
such as LTE and LTE Advance.

9 4G MOBILE NETWORK
 LTE Network Component
 4G Core Network
 Elements of 4G Core
 Functionalities of 4G Core Network Elements
9.2 THE NEED FOR 4G – LTE- GROWTH OF MOBILE DATA
For many years, voice calls dominated the traffic in mobile telecommunication
networks. The growth of mobile data was initially slow, but in the years leading up to
2010 its use started to increase dramatically. To illustrate this, Figure shows Cisco Visual
Networking Index: Global Mobile Data Traffic Forecast Update, 2016–2021 of the total
traffic being handled by networks throughout the world, in exabytes (1million terabytes)
per month. The figure covers the period from January 2016 to July 2021, during which
time the amount of data traffic increased by a factor of over 100.. For example, Figure
shows forecasts by Analysys Mason of the growth of mobile traffic in the period from
2011 to 2016. Note the difference in the vertical scales of the two diagrams. In part, this
growth was driven by the increased availability of 3.5G communication technologies.
More important, however, was the introduction of the Apple iPhone in 2007, followed by
devices based on Google‘s Android operating system from 2008. These smartphones
were more attractive and user-friendly than their predecessors and were designed to
support the creation of applications by third party developers. The result was an explosion
in the number and use of mobile applications, which is reflected in the diagrams. As a
contributory factor, network operators had previously tried to encourage the growth of
mobile data by the introduction of flat rate charging schemes that permitted unlimited
data downloads. That led to a situation where neither developers nor users were motivated
to limit their data consumption. As a result of these issues, 2G and 3G networks started to
become congested in the years around 2010, leading to a requirement to increase network
capacity.
Figure 84: Cisco Visual Networking Index: Global Mobile Data Traffic Forecast Update,
2016–2021

Figure 85: Forecasts of voice and data traffic in worldwide mobile telecommunication
networks, in the period from 2011 to 2016. Data supplied by Analysys Mason.
In the next section, we review the limits on the capacity of a mobile
communication system and show how such capacity growth can be achieved.
Capacity of a Mobile Telecommunication System In 1948, Claude Shannon
discovered a theoretical limit on the data rate that can be achieved from any
communication system [5]. We will write it in its simplest form, as follows:
C = B log2 (1 + SINR) (1.1)
Here,
SINR is the signal to interference plus noise ratio, in other words the power at the
receiver due to the required signal, divided by the power due to noise and interference.
B is the bandwidth of the communication system in Hz,
C is the channel capacity in bits per sec .
It is theoretically possible for a communication system to send data from a
transmitter to a receiver without any errors at all, provided that the data rate is less than
the channel capacity.
In a mobile communication system, C is the maximum data rate that one cell can
handle and equals the combined data rate of all the mobiles in the cell. The results are
shown in Figure , using bandwidths of 5, 10 and 20 MHz. The vertical axis shows the
channel capacity in million bits per second (Mbps), while the horizontal axis shows the
signal to interference plus noise ratio in decibels (dB):
SINR(dB) = 10 log10 (SINR)

Figure 86: Shannon capacity of a communication system, in BW of 5, 10 and 20 MHz.

9.2.1 INCREASING THE SYSTEM CAPACITY
There are three main ways to increase the capacity of a mobile communication
system, which we can understand by inspection of Equation and Figure The first, and the
most important, is the use of smaller cells. In a cellular network, the channel capacity is
the maximum data rate that a single cell can handle. By building extra base stations and
reducing the size of each cell, we can increase the capacity of a network, essentially by
using many duplicate copies of Equation.
The second technique is to increase the bandwidth. Radio spectrum is managed by
the International Telecommunication Union (ITU) and by regional and national
regulators, and the increasing use of mobile telecommunications has led to the increasing
allocation of spectrum to 2G and 3G systems. However, there is only a finite amount of
radio spectrum available and it is also required by applications as diverse as military
communications and radio astronomy. There are therefore limits as to how far this
process can go.
The third technique is to improve the communication technology that we are
using. This brings several benefits: it lets us approach ever closer to the theoretical
channel capacity, and it lets us exploit the higher SINR and greater bandwidth that are
made available by the other changes above. This progressive improvement in
communication technology has been an ongoing theme in the development of mobile
telecommunications and is the main reason for the introduction of LTE.
9.2.2 ADDITIONAL MOTIVATIONS
Three other issues are driving the move to LTE. Firstly, a 2G or 3G operator has
to maintain two core networks: the circuit switched domain for voice, and the packet
switched domain for data. Provided that the network is not too congested, however, it is
also possible to transport voice calls over packet switched networks using techniques such
as voice over IP (VoIP). By doing this, operators can move everything to the packet
switched domain, and can reduce both their capital and operational expenditure.
In a related issue, 3G networks introduce delays of the order of 100 milliseconds
for data applications, in transferring data packets between network elements and across
the air interface. This is barely acceptable for voice and causes great difficulties for more
demanding applications such as real-time interactive games. Thus a second driver is the
wish to reduce the end-to-end delay, or latency, in the network.

Thirdly, the specifications for UMTS and GSM have become increasingly
complex over the years, due to the need to add new features to the system while
maintaining backwards compatibility with earlier devices. A fresh start aids the task of
the designers, by letting them improve the performance of the system without the need to
support legacy devices.
9.3 FROM UMTS TO LTE
Figure 87: Technology Evolution

9.4 HIGH LEVEL ARCHITECTURE OF LTE
In 2004, 3GPP began a study into the long term evolution of UMTS. The aim was
to keep 3GPP‘s mobile communication systems competitive over timescales of 10 years
and beyond, by delivering the high data rates and low latencies that future users would
require. Figure shows the resulting architecture and the way in which that architecture
developed from that of UMTS.
In the new architecture, the evolved packet core (EPC) is a direct replacement for
the packet switched domain of UMTS and GSM. It distributes all types of information to
the user, voice as well as data, using the packet switching technologies that have
traditionally been used for data alone. There is no equivalent to the circuit switched
domain: instead, voice calls are transported using voice over IP. The evolved UMTS
terrestrial radio access network (E-UTRAN) handles the EPC‘s radio communications
with the mobile, so is a direct replacement for the UTRAN. The mobile is still known as
the user equipment, though its internal operation is very different from before. The new
architecture was designed as part of two 3GPP work items, namely system architecture
evolution (SAE), which covered the core network, and long term evolution (LTE), which
covered the radio access network, air interface and mobile. Officially, the whole system is

known as the evolved packet system (EPS), while the acronym LTE refers only to the
evolution of the air interface. Despite this official usage, LTE has become a colloquial
name for the whole system, and is regularly used in this way by 3GPP.
Figure 88: Evolution of the system architecture from GSM and UMTS to LTE.
9.4.1 LONG TERM EVOLUTION

The main output of the study into long-term evolution was a requirements
specification for the air interface, in which the most important requirements were as
follows.
LTE was required to deliver a peak data rate of 100 Mbps in the downlink and 50
Mbps in the uplink. This requirement was exceeded in the eventual system, which
delivers peak data rates of 300 Mbps and 75 Mbps respectively.
For comparison, the peak data rate of WCDMA, in Release 6 of the 3GPP
specifications, is 14 Mbps in the downlink and 5.7 Mbps in the uplink. (We will discuss
the different specification releases at the end of the chapter.) It cannot be stressed too
strongly, however, that these peak data rates can only be reached in idealized conditions,
and are wholly unachievable in any realistic scenario.
A better measure is the spectral efficiency, which expresses the typical capacity of
one cell per unit bandwidth. LTE was required to support a spectral efficiency three to
four times greater than that of Release 6 WCDMA in the downlink and two to three times
greater in the uplink. Latency is another important issue, particularly for time-critical
applications such as voice and interactive games. There are two aspects to this.
Firstly, the requirements state that the time taken for data to travel between the
mobile phone and the fixed network should be less than five milliseconds, provided that
the air interface is uncongested. Secondly, that mobile phones can operate in two states:
an active state in which they are communicating with the network and a low-power

standby state. The requirements state that a phone should switch from standby to the
active state, after an intervention from the user, in less than 100 milliseconds. There are
also requirements on coverage and mobility. LTE is optimized for cell sizes up to 5 km,
works with degraded performance up to 30 km and supports cell sizes of up to 100 km. It
is also optimized for mobile speeds up to 15 km per hr, works with high performance up
to 120 km per hr and supports speeds of up to 350 km per hr. Finally, LTE is designed to
work with a variety of different bandwidths, which range from 1.4MHz up to a maximum
of 20 MHz. The requirements specification ultimately led to a detailed design for the LTE
air interface.
Summarizes its key technical features, and compares them with those of WCDMA.
9.4.2 SYSTEM ARCHITECTURE EVOLUTION

The main output of the study into system architecture evolution was a
requirements specification for the fixed network , in which the most important
requirements were as follows.
The evolved packet core routes packets using the Internet Protocol (IP) and
supports devices that are using IP version 4, IP version 6, or dual stack IP version
4/version 6. In addition, the EPC provides users with always-on connectivity to the
outside world, by setting up a basic IP connection for a device when it switches on and
maintaining that connection until it switches off. This is different from the behaviour of
UMTS and GSM, in which the network only sets up an IP connection on request and tears
that connection down when it is no longer required.
The EPC is designed as a data pipe that simply transports information to and from
the user: it is not concerned with the information content or with the application. This is
similar to the behaviour of the internet, which transports packets that originate from any
application software, but is different from that of a traditional telecommunication system,
in which the voice application is an integral part of the system. Because of this, voice
applications do not form part of LTE: instead, voice calls are controlled by some external
entity such as the IP multimedia subsystem (IMS). The EPC simply transports the voice
packets in the same way as any other data stream.
Unlike the internet, the EPC contains mechanisms to specify and control the data
rate, error rate and delay that a data stream will receive. There is no explicit requirement
on the maximum time required for data to travel across the EPC, but the relevant
specification suggests a user plane latency of 10 milliseconds for a non roaming mobile,
increasing to 50 milliseconds in a typical roaming scenario [8]. To calculate the total

delay, we have to add the earlier figure for the delay across the air interface, giving a
typical delay in a non roaming scenario of around 20 milliseconds.
The EPC is also required to support inter-system handovers between LTE and
earlier 2G and 3G technologies. These cover not only UMTS and GSM, but also non
3GPP systems such as cdma2000 and WiMAX. Tables below summarize the key features
of the radio access network and the evolved packet core, and compare them with the
corresponding features of UMTS.
Key features of the radio access networks of UMTS and LTE
Table 20. Key features of the core networks of UMTS and LTE
9.5 FROM LTE TO LTE-ADVANCED
9.5.1 THE ITU REQUIREMENTS FOR 4G
The design of LTE took place at the same time as an initiative by the International
Telecommunication Union. In the late 1990s, the ITU had helped to drive the
development of 3G technologies by publishing a set of requirements for a 3G mobile
communication system, under the name International Mobile Telecommunications (IMT)
2000. The 3G systems noted earlier are the main ones currently accepted by the ITU as
meeting the requirements for IMT-2000.
The ITU launched a similar process in 2008, by publishing a set of requirements
for a fourth generation (4G) communication system under the name IMT-Advanced [9–
11]. According to these requirements, the peak data rate of a compatible system should be
at least 600 Mbps on the downlink and 270 Mbps on the uplink, in a bandwidth of 40
MHz. We can see right away that these figures exceed the capabilities of LTE.

9.6 LTE NETWORK ARCHITECTURE
Figure 89: LTE Network Architecture
Main Functions of Evolved Node B (eNB)

 It is the only network element defined as part of EUTRAN.
 It replaces the old Node B / RNC combination from 3G.
 It terminates the complete radio interface including physical layer.
 It provides all radio management functions
 An eNB can handle several cells.
 To enable efficient inter-cell radio management for cells not attached to
the same eNB, there is a inter-eNB interface X2 specified. It will allow to
coordinate inter-eNB handovers without direct involvement of EPC during
this process.
Mobility Management Entity (MME)
 It is a pure signaling entity inside the EPC.
 LTE uses tracking areas to track the position of idle UEs. The basic
principle is identical to location or routing areas from 2G/3G.
 MME handles attaches and detaches to the LTE system, as well as tracking
area updates
 Therefore it possesses an interface towards the HSS (home subscriber
server) which stores the subscription relevant information and the
currently assigned MME in its permanent data base.
 A second functionality of the MME is the signaling coordination to setup
transport bearers (LTE bearers) through the EPC for a UE.
 MMEs can be interconnected via the S10 interface

 It generates and allocates temporary ids for UEs

Serving Gateway (SGW)
 The serving gateway is a network element that manages the user data path
( bearers) within EPC.
 It therefore connects via the S1-U interface towards eNB and receives
uplink packet data from here and transmits downlink packet data on it.
 Thus the serving gateway is some kind of distribution and packet data
anchoring function within EPC.
 It relays the packet data within EPC via the S5/S8 interface to or from the
PDN gateway.
 A serving gateway is controlled by one or more MMEs via S11 interface.
 At a given time, the UE is connected to the EPC via a single Serving-GW
Packet Data Network (PDN) Gateway
 The PDN gateway provides the connection between EPC and a number of
external data networks.
 Thus it is comparable to GGSN in 2G/3G networks.
 A major functionality provided by a PDN gateway is the QoS coordination
between the external PDN and EPC.
 Therefore the PDN gateway can be connected via S7 to a PCRF (Policy
and Charging Rule Function).
 If a UE is connected simultaneously to several PDNs this may involved
connections to more than one PDN-GW
9.7 VOICE OVER LTE (VOLTE)
Voice over LTE, or VoLTE is the standards definition for the delivery of services
currently provided via Circuit Switch networks - mainly voice and SMS - over the Packet
Switched only network of LTE, leveraging the core network IP Multimedia Sub-System
(IMS). When mobile networks deploy LTE radio access technology, conformity to the
VoLTE profile provides operators with assurance of interworking between their LTE
network and the devices that connect to it, as well as providing for the expected user
experience of voice Multi-Media Telephony service and SMS. In combination with
Policy Control, IMS provides for the required QoS appropriate for voice service using
LTE radio access technology, thereby providing the user experience of voice calls that
subscribers expect. Moreover, VoLTE is designed to fully integrate with the existing user
experience that is currently implemented with circuit switched voice devices, and
therefore whether the call is a circuit switched call or a VoLTE call is transparent to the
end user (including when moving in and out of LTE coverage) and is dependent only on
which radio access technology to which the user is attached. At the same time, using new,
wideband codecs can provide higher voice quality and enhance the user experience.

Figure 90: VoLTE Architecture
9.8 CONCLUSION
In this chapter we have studied about LTE Technologies. LTE along with VoLTE
is perfect match for modern day voice and data.

E3-E4 Consumer Mobility Concept of SON
10 CONCEPT OF SON
 Concept of SON
 SON Implementation
 Issues in SON implementation
 SON Data Creation
 Automatic handover in SON
10.2 INTRODUCTION
Self Organising Network (SON) is a collection of procedures (or functions) for
automatic configuration, optimization, diagnostication, and healing of cellular networks.
It is considered to be a major necessity in future mobile networks and operations mainly
due to possible savings in capital expenditure (CAPEX) and operational expenditure
(OPEX) by introducing SON.
The drivers for SON are:

 The number and complexities of networks, nodes, elements and
parameters
 Existence of multi-technology, multi-vendor and multi-layer operations
within the network
 Traffic growth and capacity management
 Consistent quality and service availability
 The need for knowledge-based and interactive networks
Figure 91: Network without SON Capability

Figure 92: Network with SON Capability
Figure 93: Benefits of SON

The main benefits of introducing SON functions in cellular networks are as
follows.
 Reduced installation time and costs.
 Reduced OPEX due to reductions in manual efforts in connection with
monitoring, optimizing, diagnosing, and healing of the network.
 Reduced CAPEX due to more optimized use of network elements and
spectrum.
 Improved user experience.
 Improved network performance
10.3 SELF ORGANIZING NETWORKS (SON) CONCEPT
The SON functions are usually categorized into three main groups: Self-
configuration, self-optimization, and self-healing. It should be noted that a given SON
function can belong to more than one of these categories.

Figure 94: Functions of SON
Figure 95: 3GPP SON FRAMEWORK

Network Lifecycle
Planning Deployment Optimization Maintenance
Self-Planning Self-Configuring Self-Optimizing Self-Healing

- Automatically derive - Plug-n-Play Hardware - Automatic Neighbor - Auto Cell
few Radio - Self-Configuration Relation Outage
parameters for eNBs Radio Parameters Optimization Detection
which will be . Initial PCI, - Mobility - Auto Cell
established. Robustness Outage
. Initial NR,
- Reduce amount of . Initial PRACH configuration Optimization Compensation
- Mobility Based
manual pre- - Automatic IP Acquisition Load balancing
planning - Automatic Neighbor Lists
Activities - RACH optimization
- Automatic - Energy Cost
- Reduce self- Connectivity
configuration Optimizatio
establishment n
errors - Self-test and - Coverage &
S/W download Capacity
Optimization
Figure 96: SON Technology
10.3.1 SELF CONFIGURATION
The Self-configuration SON is a collection of algorithms that aims at reducing the

amount of human intervention in the overall installation process by providing ―plug and
play‖ functionality in network elements such as the E-UTRAN NodeBs (eNBs). This will
result in faster network deployment and reduced costs for the operator in addition to a
more integral inventory management system that is less prone to human errors. This
process involves three key operations: set-up, authentication and radio configuration.
Self-configuration is a broad concept which involves several distinct functions

that are covered through specific SON features, such as automatic software management,
self test, Physical cell ID configuration (PCI), and automatic neighbor relations (ANR).
The latter function is not only used during installation but is also an important part during
normal operations.
The self-configuration should take care of all soft- configuration aspects of an

eNB once it is commissioned and powered up for the first time. It should detect the
transport link and establish a connection with the core network elements, download and
upgrade to the latest software version, set up the initial configuration parameters
including neighbor relations, perform a self-test, and finally set itself to operational mode.
In order to achieve these goals, the eNB should be able to communicate with several
different entities.

Figure 97: Self Configuration Procedure

The self-configuration actions will take place after the eNBs physically installed,
plugged to the power line and to the transport link. When it is powered on, the eNB will
boot and perform a self test, followed by a set of self-discovery functions, which include
the detection of the transport type, tower-mounted amplifier (TMA), antenna, antenna
cable length and auto-adjustment of the receiver-path.
After the self-detection function, the eNB will configure the physical transport link
autonomously and establish a connection with the DHCP/DNS (dynamic host configura-
tion protocol/domain name server) servers, which will then provide the IP addresses for
the new node and those of the relevant network nodes, including serving gateway,
mobility management entity (MME), and configuration server. After this, the eNB will be
able to establish secure tunnels for operations administration and maintenance (OAM),
S1, andX2linksandwillbereadytocommunicatewiththeconfiguration server in order to
acquire new configuration parameters.
One of the OAM tunnels created will communicate the eNB with a dedicated
management entity, which contains the software package that is required to be installed.
The eNB will then download and install the corresponding version of the eNB software,
together with the eNB configuration file. Such configuration file contains the
preconfigured radio parameters that were previously planned. A finer parameter
optimization will take place after the eNB is in operational state (self-optimization
functions).
The self-configuration SON functions were among the first standardized by 3GPP
(release 8) and have been more or less stable since then. From the roadmaps of different
vendors it can be concluded that self-configuration SON is available and mature. These
SON features will be extremely useful in the rollout phase to reduce the installation time
compared with ordinary installation procedures, and also later when new eNBs are added

to increase the network capacity. The actual decrease in OPEX is not easy to give since
the corresponding installation without any (self) automatic features is difficult to foresee.
The self configuration procedures for LTE presents three automated processes:
Self configuration of eNB, Automatic Neighbour Relations (ANR) and Automatic
Configuration of Physical Cell ID (PCI).
10.3.2 SELF CONFIGURATION OF ENB
This is relevant to a new eNB trying to connect to the network. It is a case where
the eNB is not yet in relation to the neighbour cells, but to the network management
subsystem and the association of the new eNB with the serving gateway (S-GW). It is the
basic set-up and initial radio configuration. The stepwise algorithm for self configuration
of the eNB is outlined:
1. The eNB is plugged in/powered up.
2. It has established transport connectivity until the radio frequency transmission is
turned on.
3. An IP address is allocated to it by the DHCP/DNS server.
4. The information about the self configuration subsystem of the Operation and
Management (O & M) is given to the eNB.
5. A gateway is configured so that it connects to the network. Since a gateway has
been connected on the other side to the internet, therefore, the eNB should be able
to exchange IP packets with the other internet nodes.
6. The new eNB provides its own information to that self configuration subsystem
so that it can get authenticated and identified.
7. Based on these, the necessary software and information for configuration (radio
configuration) are downloaded.
8. After the download, the eNB is configured based on the transport and radio
configuration downloaded.
9. It then connects to the Operation Administration Management (OAM) for any other
management functions and data-ongoing connection.
10. The S1 and X2 interfaces are established.
10.3.3 AUTOMATIC NEIGHBOUR RELATIONS (ANR)
ANR is an automated way of adding/deleting neighbour cells. ANR relies on user

equipment (UE) to detect unknown cells and report them to eNBs. Its operation can be
summarized into: measurements, detection, reporting, decision (add/delete cell) and
updating.

Figure 98: ANR with help of UE Measurement

The step-by-step ANR procedure is outlined:
1. During measurements, the UE detects PCI from an unknown cell.
2. The UE reports the unknown PCI to the serving eNB via Radio Resource
Controller (RRC) reconfiguration message.
3. The serving eNB requests the UE to report the E-UTRAN Cell Global ID (ECGI)
of the target eNB. The eNB is able to detect devices faster that way.
4. The UE reports ECGI by reading the broadcast channel (BCCH) channel.
5. Based on the ECGI, the serving eNB retrieves the IP address from the Mo- bility
Management Entity (MME) to further set-up the X2 interface, since an initial X2
interface set-up would have happened during the target eNB‘s self configuration.
6. Function is extended to inter-RAT and inter-frequency cases with suitable
messaging.
10.3.4 ANR WITH OPERATION ADMINISTRATION & MANAGEMENT
(OAM) SUPPORT
ANR with OAM support is a more centralized system of operation. The OAM is
the management system of the network. ANR procedures with OAM support are outlined:
 The new eNB registers with OAM and downloads the neighbour
information table which includes the PCI, ECGI and IP addresses of the
neighbouring eNBs.
 The neighbours update their own tables with the new eNB information.
 The UE reports the unknown PCI to the serving eNB.
 The eNB sets-up the X2 interface using the neighbour information table
formed previously.

10.3.5 AUTOMATIC CONFIGURATION OF PHYSICAL CELL

IDENTIFICATION (PCI).
The automatic configuration of physical cell ID (PCI) for eNBs in LTE was
standardised in 3GPP release 8 as part of ―eNB self configuration.‖ PCI is a locally
defined identifier for eNBs with a restricted range (up to 504 values) and must be reused
throughout the network. The PCI numbering of eNBs must locally be unique so that the
UEs may be able to communicate and possible perform handovers. The goal of PCI
configuration is to set the PCI of a newly introduced cell. The PCI is contained in the
SCH (synchronization channel) for user equipment (UE) to synchronize with the cell on
the downlink. When a new eNB is established, it needs to select PCIs for all the cells it
supports. Since the PCI parameters have a restricted value range, the same value needs to
be assigned to multiple cells throughout the network and must be configured collision
free, that is, the configured PCI needs to be different from the values configured in all the
neighbouring cells.
In today‘s algorithms for automatic PCI assignments, conflicts may occur in the
way they are allocated. Therefore, to achieve the aim of SON, work is currently being
done to ensure automatic configuration of PCIs become a part of the standardized
configuration.
PCI configuration must satisfy two rules:

 Collision Free: The PCI of one cell should not be the same as those of his
neighbor cells.
 Confusion Free: The PCI of the neighbor cells should not be the same.
PCI B PCI B
PCI A PCI A PCI A PCI B
PCI A PCI A PCI B PCI C
Collision Based Collision Free Confusion Based Confusion Free

Figure 99: PCI Solution
10.3.6 SELF OPTIMIZATION
SON self-optimization functions are aiming at maintaining network quality and

performance with a minimum of manual intervention from the operator. Self-optimization
functions monitors and analyzes performance data and automatically triggers
optimization action on affected network element(s) when necessary. This significantly
reduces manual interventions and replaces them with automatic adjustments keeping the
network optimized at all times. Self-optimizing SON functions make it possible to
introduce new automatic processes that are too fast, and/or too complex to be
implemented manually. This will improve the network performance by making the

network more dynamic and adaptable to varying traffic conditions and improve the user
experience.
Self configuration alone is not sufficient to guarantee effective management of the

end-to-end network, the need for knowledge-based end-to-end monitoring is also very
crucial. After configurations, automated processes/algorithms should be able to regularly
compare the current system status parameters to the target parameters and execute
corrective actions when required. This process ensures optimum performance at all times.
This process is known as Self Optimization.
Some of the most important self-optimization SON use cases are:
(i) Physical cell ID(PCI);
(ii) Automatic neighbour relations(ANR);
(iii) Inter-cell Interference coordination(ICIC);
(iv) Mobility robustness optimization(MRO);
(v) Mobility load balancing optimization (MLB).
The two first use cases, PCI and ANR, may as well be categorized as self-
configuration algorithms since they will be part of initial configuration procedures, but
will also play an important part in normal operation and therefore may be viewed as being
self optimization procedures.
10.3.7 PHYSICAL CELL ID CONFIGURATION (PCI)
The PCI automatic configuration was one of the first SON functions to be
standardized by 3GPP. The self- configuration feature seems to be quite mature and all of
the main vendors have this function implemented in their eNBs. Some vendors report
tests with 100% handover success rate in networks where new eNB are introduced and
the Automatic PCI Optimization are applied. The physical cell ID configuration is a SON
function that should be implemented at eNB rollout.
10.3.8 AUTOMATIC NEIGHBOUR RELATIONS (ANR)
One of the more labour intense areas in existing radio technologies is the handling
of neighbour relations for handover. A neighbour relation is information that a neighbour
cell is a neighbour to an eNB. Each eNB holds a table of detected neighbour cells which
are used in connection with handovers. Updating automatic neighbour relations (ANR) is
a continuous activity that may be more intense during network expansion, but is still a
time consuming task in mature networks. The task is multiplied with several layers of
cells when having several networks to manage. With LTE, one more layer of cells is
added; thus, optimization of neighbour relations may be more complex. Due to the size of
the neighbouring relation tables in radio networks, it is a huge task to maintain the
neighbour relations manually. Neighbour cell relations are therefore an obvious area for
automation, and ANR is one of the most important features for SON. To explore its full
potential, ANR must be supported between network equipment from different vendors.
ANR was therefore one of the first SON functions to be standardized in 3GPP.

10.3.9 INTER-CELL INTERFERENCE COORDINATION (ICIC).
The main idea behind inter-cell interference coordination (ICIC) is to coordinate

transmissions in different cells in such a way that the inter-cell interference and/or the
effect of it is reduced. With the currently proposed solutions this is achieved by letting
each cell omit using some of the spectrum resources (frequency/time slots/power) in order
to reduce interference. Omitting to use spectrum resources implies that some capacity is
lost, so the gains obtained by operating in an environment with less interference must
more than compensate for this loss. The most important gain that can be achieved by
ICIC is the ability to provide a more homogeneous service to users located in different
regions of the network, especially by improving the cell-edge performance.
Mutual interference may occur between the cells in an LTE network. Interference
unattended to leads to signal quality degradation. Inter-cell interference in LTE is
coordinated based on the Physical Resource Block (PRB). It involves coordinating the
utilization of the available PRBs in the associated cells by introducing restrictions and
prioritization, leading to significantly improved Signal to Interference Ratio (SIR) and the
associated throughput. This can be accomplished by adopting ICIC RRM (Radio
Resource Management) mechanisms through signalling of Overload Indicator (OI), High
Interference Indicator (HII), or downlink transmitter power indicator.
Multi-layer heterogeneous network layout including small cell base stations are
considered to be the key to further enhancements of the spectral efficiency achieved in
mobile communication networks. It has been recognized that inter-cell interference has
become the limiting factor when trying to achieve not only high average user satisfaction,
but also a high degree of satisfaction for as many users as possible.
Figure 100: ICIC Use Case

The servicing operator for each cell carries out interference coordination, by
configuring the ICIC associated parameters such as reporting thresholds/periods and
prioritized resources. The ICIC SON algorithm is responsible for the automatic setting
and updating of these parameters.
The ICIC SON algorithm work commenced in Release 9 but was not completed
here. It is targeted at self configuration and self optimization of the control parameters of
ICIC RRM strategies for uplink and downlink. To achieve interference coordination, the
SON algorithm leverages on exchange of messages between eNBs in different cells
through the X2 interface. The SON algorithm enables automatic configuration/adaptation
with respect to cell topology, it requires little human intervention and leads to optimized
capacity in terms of satisfied users.
10.3.10 MOBILITY ROBUSTNESS / HANDOVER OPTIMIZATION (MRO).
Handover coordination is very necessary in ensuring seamless mobility for user

devices within a wireless network. In 2G/3G systems, setting handover parameters is a
manual and time consuming task and sometimes too costly to update after initial
deployment. Mobility Robustness Optimization (MRO) automates this process to
dynamically improve handover operations within the network, provide enhanced end user
experience and improved network capacity.
To achieve this aim, the question to be critically answered is ―What triggers

handover?‖ Therefore, 3GPP categorize handover failures into:
 Failures due to too late handover triggering
 Failures due to too early handover triggering
 Failures due to handover to a wrong cell
Figure 101: Too Late Handover

Figure 102: Too Early Handover
Figure 103: Wrong Handover

Also, unwanted handovers may occur subsequent to connection set-up, when cell-
reselection parameters are not in agreement with the handover parameters.
Therefore, the MRO algorithm is aimed at detecting and minimizing these failures
as well as reducing inefficient use of network resources caused by unnecessary handovers
and also reducing handovers subsequent to connection set-up.
As specified by 3GPP, enabling MRO requires that:
a) The relevant mobility robustness parameters should be automatically
configurable by the eNB SON entities;
b) OAM should be able to configure a valid range of values for these
parameters; and
c) The eNB should pick a value from within this configured range, using
vendor- specific algorithms for handover parameter optimization.

For efficient/effective MRO, there must be linkage to policies to ensure other

parameters/QoE is not affected. This implies that all parameter modifications must align
with other similar interacting SON algorithms (such as Load Balancing). Therefore, there
is a need for communication between SON algorithms to resolve probable conflicts and
ensure stability.
During roll-out of an LTE network, there will be areas having limited LTE
coverage. Enabling handover from LTE to existing 2G/3G systems will therefore become
an important feature. In this scenario, it will be very important to maintain a low drop rate
for UEs moving from LTE to 2G/3G.
A SON MRO mechanism was introduced in release 10 for the purpose of

detecting unnecessary inter-RAT handover. During the handover preparation the source
RAT (LTE) requests optionally the target RAT (GSM/UMTS) to perform UE
measurements of the source RAT. The measurements start following the successful
handover, and the measurement duration is one of the parameters provided by the source
RAT (max 100 seconds). The measurements stop if a new inter-RAT HO takes place
during this time interval.
If during this period the UE measurements shows that the source RAT quality
remains better than a configurable threshold, the target RAT will report to the source
RAT that the handover could have been avoided. The source RAT may then take
corrective action, for example, adjust the handover threshold or increase time-to-trigger
setting for handovers to the concerned inter-RAT target cell.
MRO is very useful in the LTE network deployment process, reducing the need
for extensive drive-testing. Since the LTE coverage often will be spotty in the beginning,
inter- RAT MRO will also be very useful. For networks in operation MRO will ensure
that the handover thresholds are optimal at all times and remove the need for manual task
such as drive- testing, detailed system log, and post processing.
The benefits of MRO will be especially useful in HetNets, which are more
dynamic where small cells appear and disappear. However, MRO solutions for HetNets
are still not fully developed.
MRO is not critical for the operation of LTE networks today. The networks are
usually stable macro networks with low to moderate traffic load, and most of the
terminals are PC dongles and hence usually stationary when used. However, MRO will
become more important as the penetra- tion of handheld terminals becomes larger, the
traffic load increases and micro-, pico-, and femto-cells are introduced in the network. It
will be beneficial to include MRO in LTE networks from the start but it will not be a
critical function when the network is a stable macro network, but will offer reduced
installation time and reduced OPEX costs. As the number of small cells in the network
increase, MRO will be become more important and an MRO function capable of handling
HetNet scenarios should be included.
10.3.11 MOBILITY LOAD BALANCING OPTIMIZATION (MLB)
The OBJECTIVES of mobility load balancing (MLB) is to intelligently spread

user traffic across the system‘s radio resources in order to optimize system capacity while
maintaining quality end-user experience and performance. Additionally, MLB can be

used to shape the system load according to operator policy, or to empty lightly loaded
cells which can then be turned off in order to save energy. The automation of this
minimizes human intervention in the network management and optimization tasks.
Basic functionality of mobility load balancing was defined in Release 9. Release

10 added enhancements that addressed inter-RAT scenarios and inter-RAT information
exchange.
Support for mobility load balancing consists of one or more of following

functions:
(i) load reporting;
(ii) load balancing action based on handovers;
(iii) adapting handover and/or reselection configuration.
Figure 104: Mobility Load Balancing

Triggering of each of these functions is optional and depends on implementation.
Current implementations of the MLB function are relatively simple. Moving load
between cells are achieved by adjusting the handover thresholds and hence the position
of the cell boundaries. As this can affect the handover performance, this must be
coordinated with the MRO SON function. This can, for example, be achieved by letting
the MRO function define an allowed interval for the handover threshold. The MLB
function can then adjust the handover threshold within this interval.
One of the weaknesses of current MLB implementations is that the UEs that are
moved from one cell to another do not usually constitute the optimal choice and can even
cause problems in the target cell. For example, moving an UE that uses a lot of capacity
can cause overloading in the target cell. This will lead to new MLB-based handovers and,
if necessary precautions are not taken, even to ping-pong effects.

It should be notated that estimating what load an UE will represent in the new cell
is not straightforward. The radio conditions in the new cell will be different from what it
was in the original cell, hence the radio resources (i.e., the air time) required for a certain
capacity will also be different. In the downlink the estimation can be done based on
RSRP/RSRQ (reference signal received quality) reports from the UE. However, similar
information is not available for uplink and extended information exchange between the
eNBs is required.
MLB of idle mode UEs is more difficult than for active mode UEs. There is
currently no way to know exactly on which cell an idle mode UE is camping. The only
time the system becomes aware of the exact cell an UE is in, while in idle mode, is
when the tracking area of the user changes and a tracking area update message is sent by
the UE. Therefore, while parameters that control how and when a UE performs cell
reselection (idle handover) are modi- fiable, there is no direct measurement mechanism
for the system to determine when there are ―too many‖ idle users. In current
implementations the idle mode load balancing is usually done by adjusting the cell
reselection parameters for the idle users based on the current active user condition.
The load balancing can be operated in different ways. One possibility is to only
activate MLB when a cell becomes congested. Another possibility is to let MLB be a
more continuous process trying to keep the load in different cells balanced at all times. In
the latter case careful consideration should be given to the network signalling load.
Currently, the rear eliminated knowledge on the advantages and disadvantages of
operating MLB in different ways, and further studies and field trials should be performed.
The way of operation should be configurable by the operator through the network
management system.
To increase the effectiveness of the MLB function, especially in HetNet scenarios

with many small cells, it will be necessary to develop more advanced algorithms. One
potential improvement is to choose which UEs should be moved from one cell to another
more carefully. The choice could be based on such parameters as capacity and QoS
requirements, possibly including predicted values for these parameters based on historical
information. The decision on what cells UEs should be moved to and from could also be
performed more optimally, for example, based on current and historical statistical data on
the load in different cells.
Basing the MLB related decisions on more information requires extended

exchange of data between eNBs, which requires standardization of the necessary
signalling support. Another area for improvement of MLB is its interworking with other
SON functions, especially with MRO. In most cur-rent MLB implementations, MRO has
priority and MLB has to adapt to the adjustments done by MRO. This significantly limits
the MLB operation. For inter-RAT and inter-frequency handovers, MLB should probably
have priority over MRO.
MLB also significantly overlap with the traffic steering and must be coordinated
closely with this function.
In newly deployed LTE networks the traffic load will be modest and there will be
little need for load balancing between LTE cells and between LTE and 2G/3G cells. As
traffic increases, the usefulness of the MLB function also increases. It is therefore not
necessary to include MLB in LTE deployments from the start. The usefulness of MLB

increases as the network load increase and becomes important when the network develops
in to a HetNet with many small cells.
10.3.12 COVERAGE AND CAPACITY OPTIMIZATION.
Coverage and Capacity Optimization (CCO) is a self optimization technique used

in managing wireless networks according to coverage and capacity. CCO measures the
health of the network and compares with performance target and policies as defined by
individual operators. It has been identified by 3GPP as a crucial optimization area in
which the SON algorithm determines the optimum antenna configuration and RF
parameters (such as UL power control parameters) for the cells that serve a particular area
and for a defined traffic situation, after the cells have been deployed.
For successful implementation of CCO SON algorithms, there is need to take into
serious consideration, the difference between coverage optimization and capacity
optimization. Coverage optimization involves identifying a ―hole‖ in the network and
then adjusting parameters of the neighbouring cells to cover the hole. However, in-
creasing cell coverage affects spectral efficiency negatively due to declining signal
power, which results in lesser capacity. It is therefore not possible to optimize coverage
and capacity at the same time, but a careful balance and management of the trade- offs
between the two will achieve the optimization aim.
Adapting to network changes (such as addition/removal of eNBs and change in

user distribution) manually is costly and time consuming. Hence, the CCO algorithms
operate endlessly, gathering measurements and executing actions if needed. CCO is a
slow process in which decisions are made based on long-run statistics.
Below is a list of functions the CCO algorithm is to perform as identified by

3GPP; but 3GPP does not specify how to perform these functions but are operator-
defined:
• E-UTRAN coverage holes with 2G/3G coverage.
• E-UTRAN coverage holes without any other coverage.
• E-UTRAN coverage holes with isolated island coverage.
• E-UTRAN coverage holes with overlapping sectors.
10.3.13 RANDOM ACCESS CHANNEL (RACH) OPTIMIZATION.
RACH configuration within a network has major effects on the user experience
and the general network performance. RACH configuration is a major determinant for
call setup delays, hand-over delays and uplink synchronized state data resuming delays.
Consequently, the RACH configuration significantly affects call setup success rate and
hand-over success rate. This configuration is done in order to attain a desired balance in
the allocation of radio resources between services and the random accesses while
avoiding extreme interference and eventual degradation of system capacity. Low
preamble detection probability and limited coverage also result from a poorly configured
RACH. The automation of RACH configuration contributes to excellent performance
with little/no human intervention; such that the algorithm monitors the current conditions
(e.g. change in RACH load, uplink interference), and adjusts the relevant parameters as
necessary. RACH parameter optimization provides the following benefits to the net-
work:
• Short call setup delays resulting in high call setup rates

• Short data resuming delays from UL unsynchronized state

• Short handover delays resulting in high handover success rate
More generally, RACH optimization provides reduced connection time, higher
throughput, and better cell coverage and system capacity. All the UE and eNB mea-
surements are provided to the SON entity, which resides in the eNB. An eNB exchanges
information over the X2 interface with its neighbours for the purpose of RACH
optimization. The PRACH Configuration is exchanged via the X2 setup and eNB
configuration update procedures. An eNB may also need to communicate with the O&M
in order to perform RACH optimization.
10.3.14 ENERGY SAVING
Mobile network operators are very keen on finding network energy saving
solutions to minimize power consumption in telecommunication networks as much as
possible. This will lead to reduced OPEX (since energy consumption is a major part of an
operator‘s OPEX) and enable sustainable development on the long- run. Energy saving is
very crucial today, especially with the increasing deployment of mobile radio network
devices to cope with the growing user capacity.
OPEX due to energy consumption within a network can be significantly

controlled by: a) the design of low-powered network elements; b) temporarily powering
off un- used capacity; and c) working on the power amplifiers, since they consume
majority of the available energy in a wireless network.
The normal practice is the use of modems to put the relevant network elements in
stand-by mode. These modems have a separate management system. To achieve an
automated system of saving energy, the network elements should be able to remotely
default into stand-by mode using the minimum power possible when its capacity is not
needed, and also switch-off stand-by mode remotely when needed, without affecting user
experience.
The energy saving solutions in the E-UTRAN, which are being worked on by
3GPP, to be used as the basis for standardization and further works are: Inter-RAT energy
savings; Intra-eNB energy savings; and Inter-eNB energy savings 3GPP has also
stipulated the following conditions under which any energy saving solutions should
operate, since energy savings should ideally not result in service degradation or network
incompetence:
 User accessibility should be uncompromised when a cell switches to
energy saving mode.
 Backward compatibility and the ability to provide energy savings for Rel-
10
 Network deployment that serves several legacy UEs should be met.
 The solutions should not impact the physical layer.
 The solutions should not impact the UE power consumption negatively.
10.3.15 SELF-HEALING
Self-healing functionality was not initially defined a part of the 3GPP SON
functionality, but it was taken into the SON standards in release 9 and 10, by 3GPP .

Self-healing is a collection of SON procedures which detects problems and solves

or mitigates these to avoid user impact and to significantly reduce maintenance costs. Self
healing involves automatic detection and localization of failures and the application of the
necessary algorithms to restore system functionality. Self- healing is triggered by alarms
generated by the faulty network elements. If it finds alarms that it might be able to correct
or minimize the effects of, it gathers more necessary correlated information (e.g.,
measurements, testing results, and so forth), does deep analysis, and then trigger the
appropriate actions.
The two major areas where the self-healing concept could be applied are as
follows.
(1) Self-diagnosis: create a model to diagnose, learning from past experiences.
(2) Self-healing: automatically start the corrective actions to solve the
problem.
Making use and analyzing data from the current optimization tools (alarm
supervision system, OAM system, network consistency checks), optimizers can decide
if network degradation occurs, which is the most likely cause, and then perform the
needed corrections to solve the problem. The experience of optimizers in solving such
problems in the past, and the access to a database of historic solved problems is very
useful to improve the efficiency in finding solutions.
This whole optimization process could be enhanced in two steps as follows.

(i) Diagnosis model creation based on the experience of already solved
problems, using a database with faults and their symptoms. Automatic
troubleshooting action can be done without human intervention.
(ii) Self-test results from the periodic execution of consistency checks would
help during the self diagnosis phase, to address better the healing process.
In the recommendation three different Self-healing SON functions are defined:
(i) cell outage,
(ii) self-recovery of network element (NE) software and
(iii) self-healing of board faults.
10.3.16 CELL OUTAGE.
This SON function has two basic components, namely, Cell Outage Detection
(COD) and Cell Outage Compensation (COC) .
COD uses a collection of evidence and information to determine if a particular

cell is not working correctly. The equipment usually detects faults in itself automatically.
But in a situation where the detection system itself is faulty and has therefore failed to
notify the OAM, such unidentified faults of the eNBs are referred to as sleeping cells.
Cell Outage Detection and Compensation automatically handles these eNB failures by
combining several individual mechanisms to determine if an outage has occurred, and
then compensating for the failures after soft recovery techniques fail to restore normal
service. The automated detection mechanism ensures the operator knows about the fault
before the end user. The SON compensation system temporarily mitigates the problem.
10.4 3GPP SON EVOLUTION
Self Organizing Networks (SON) developed by 3GPP, using automation, ensures
operational efficiency and next generation simplified network management for a mobile

wireless network. The introduction of SON in LTE therefore brings about optimum
performance within the network with very little human intervention.
3GPP standardization in line with SON features has been targeted at favouring
multi- vendor network environments. Many works are on-going within 3GPP to define
generic standard interfaces that will support exchange of common information to be
utilized by the different SON algorithms developed by each vendor. The SON
specifications are being developed over the existing 3GPP network management
architecture defined over Releases 8, 9, 10 and beyond.
Release 8 marked the first LTE network standardization; therefore, the SON
features here focused on processes involved with initial equipment installation and
integration. Release 8 SON activities include:
 eNB Self Configuration: This involves Automatic Software Download and
dynamic configuration of X2 and S1 interfaces.
 Automatic Neighbour Relation (ANR)
 Framework for PCI selection
 Support for Mobility Load Balancing
Release 9 marked enhancements on Release 8 LTE network; therefore, SON tech-
niques in Release 9 focused on optimization operations of already deployed networks.
Release 9 SON activities include:
 Automatic Radio Network Configuration Data Preparation
 Self optimization management
 Load Balancing Optimization
 Mobility Robustness/Handover optimization (MRO)
 Random Access Channel (RACH) Optimization
 Coverage and Capacity optimization (CCO)
 Inter-Cell Interference Coordination (ICIC)
Release 10 SON in LTE activities include enhancements to existing use cases and
definition of new use cases as follows:
 Self optimization management continuation: CCO and RACH
 Self healing management: Cell Outage Detection and Compensation
 OAM aspects of Energy saving in Radio Networks
 LTE self optimizing networks enhancements
 Enhanced Inter-Cell Interference Coordination (eICIC)
 Minimization of Drive Testing
 UTRAN SON management: ANR
 LTE SON coordination management
 Inter-RAT Energy saving management
 Further self optimizing networks enhancements: MRO, support for Energy
saving.

 Enhanced Network-Management-Centralized CCO

 Multi-vendor plug and play eNB connection to the network.

 The 3GPP SON standardization is a work in progress and is expected to
cover all focus areas of wireless technology evolution, as it relates to
network management, optimization and troubleshooting in multi-tech,
multi-cell, multi-actor and heterogeneous networks.
10.5 CONCLUSION
Manual tuning of radio network is not possible as it involve lot parameter
management and leads to false decision and poor network. SON is the best practice, but
data inputted must be correct.

E3-E4 Consumer Mobility Network Optimization Using DTT reports
11 NETWORK OPTIMIZATION USING DTT REPORTS

AND SON DATA MANAGEMENT
 Radio Network Optimization
 Optimization of the cost and guaranteeing the network service quality
 Efficient utilization of resources
 Drive Test Tool and Parameters
 SON architecture and data management
11.2 RADIO NETWORK OPTIMIZATION
Once some hundreds of sites are on air, it becomes necessary to perform
optimization on the network in order to maximize benefits while minimizing capital and
operation costs for operators. This section, in fact, deals with all aspects of optimizing a
GSM network starting from standard operations and ending with specific trials, studies
and fine-tuning. Before the network is commercially launched, the radio network
optimization process starts and then continues during the life of the network.
Depending on the type of network management system, either in the BSC or in the
BTS, each cell reports thousands of statistics about all relevant behaviors (number of
attempts, failures, successes, during call, handover, setup, etc.). These statistics are
reported to the Network Management System (NMS) as counters. To facilitate
interpretation of the behavior, a set of key performance indicators (KPIs) is defined out of
formulas using pure counters. Each operator chooses its own KPIs and sets, according to
specific criteria, some OBJECTIVES to be met in order to achieve a good end user
perception of the service offered and also in order to benchmark one network with other
operators.
Another aspect that is important in the optimization phase deals with drive tests.
In fact, while statistics give a general idea of the cell‘s behavior at a certain period, field
measurements give a one instant scenario of one area‘s behavior during a call. Different
tools can be used to perform drive tests. Each specific tool is able to standard reporting at
the signal level, quality and site information (cell identity, BCCH, mobile allocation list,
best neighbors, etc.).
Statistics and drive tests are the main methods used to monitor the network‘s
performance. However, other specific methods can also be used. Tracing catches one
object‘s behavior (TRX, cell, BTS or BSC) during a certain period and regardinga
specific event (SDCCH allocation, conversation phase of a voice call, etc.) or a set of
successful events (IMSI attach, paging, call setup, location update, etc.). Alarm
monitoring, transmission network auditing and network switching subsystem (NSS)
performance follow-up are also important in the sense that they give an idea of hardware
problems or parameter errors.
After deep analysis, actions are then taken to correct and improve performance.
All the above-described methods help the optimization engineers to identify the origin of
the problem from the office while applying several analysis methods. Another aspect is,
however, very important: field knowledge. Correct site re-engineering is the basis for a
good performing network. Frequency planning review is also a key step in the process.

Network planning optimization consists of various operations, all leading to the

improvement of KPIs. input data for starting optimization are KPI values in a certain area.
Depending on whether the area KPI is greater or less than the target, troubleshooting on a
cell basis starts and statistics can be extracted weekly, daily or even on an hourly basis
from the NMS. The Call Setup Success Rate (CSSR) and dropcall rate (DCR) are the
main KPIs relevant to operator losses.
11.3 DRIVE TESTING
11.3.1 WHAT IS DRIVE TEST
Drive Testing is a method of measuring and assessing the coverage, capacity and
Quality of Service (QoS) of a mobile radio network.Drive testing is principally applied in
both the planning and optimizationstage of network development.Drive tests are the most
common measurement tool used by operators, to probe the quality status and solve
network problems.
11.3.2 DRIVE TESTING
The technique consists of using a motor vehicle containing mobile radio network
air interface measurement equipment that can detect and record a wide variety of the
physical and virtual parameters of mobile cellular service in a given geographical area.
It is conducted for checking the coverage criteria of the cell site with the RF drive
test tool.
The data collected by drive test tool in form of Log files are assessed to evaluate
the various RF parameters of the network.
11.3.3 DATA ACQUIRED FROM DRIVE TEST:
The dataset collected during drive testing field measurements can include
information such as
 Signal intensity
 Signal quality
 Interference
 Dropped calls
 Blocked calls
 Call statistics
 Service level statistics
 QoS information
 Handover information
 Neighbouring cell information
 GPS location co-ordinates
11.3.4 TYPES OF DRIVE TESTING
 Network Benchmarking
 Optimization & Troubleshooting
 Service Quality Monitoring
Network Benchmarking

Sophisticated multi-channel tools are used to measure several network

technologies and service types simultaneously to very high accuracy and collect accurate
competitive data on the true level of their own and their competitors technical
performance and quality levels
Optimization & Troubleshooting
Optimization and troubleshooting information is more typically used to aid in

finding specific problems during the rollout phases of new networks or to observe
specific problems reported by consumers during the operational phase of the network
lifecycle.
Service Quality Monitoring
Service quality monitoring typically involves making test calls across the network
to a fixed test unit to assess the relative quality of various services using Mean opinion
score (MOS).Service quality monitoring is typically carried out in an automated fashion.
The results produced by drive testing for each of these purposes is different.
11.3.5 DRIVE TEST EQUIPMENT
Following Resources/Equipments are required for drive test

 A Laptop
 Drive Test software with Dongle/License Key
 GPS (Global Positioning system) to provide location information
 One or Multiple Handsets Compatible with the Drive Test Software
 Scanner (Optional)
 Database of Existing Network (Cell site database)
 A Suitable Vehicle
11.3.6 CONNECTIVITY OF DRIVE TEST TOOL
As shown in figure, all the equipment‘s (GPS, Mobile Handsets, Dongle) are
connected to Laptop via USB ports. Normally antenna type GPS (with magnetic base to
stick on top of vehicle) is used with drive test tool.
Figure 105: Connectivity of Drive Test Tool

11.3.7 DRIVE TEST TOOLS

Data Collection Tools
 TEMS Investigation
 Nemo Outdoor
 JDSU E6474A
 Accuver XCAL
Post-processing tools
 Actix Analyzer/Spotlight
 Accuver XCAP
 TEMS Discovery LTE
11.3.8 LTE DRIVE TEST PARAMETERS
 RSRP: Reference Signal Received Power.
 RSRQ: Reference Signal Received Quality.
 RSSI: Received Signal Strength Indicator.
 SINR : Signal to Interference Noise Ratio
 CQI: Channel Quality Index.
 PCI: Physical Cell Identity.
 BLER: Block Error Ratio.
 DL Throughput: Down Link Throughput.
 UL Throughput : Up Link Throughput
This is the common key performance parameters for LTE drive test parameter we
have to work out for LTE drive test task.
RSRP:
It indicates coverage. RSRP is the average power received from a single
Reference signal, and its typical range is around -44dbm (good) to -140dbm (bad).
RSRQ:
RSRQ – Indicates quality of the received signal and its range is typically -19.5dB
(bad) to -3dB (good).
RSSI:
RSSI (Received Signal Strength Indicator) is a parameter which provides
information about total received wide-band power (measure in all symbols) including all
interference and thermal noise.
RSSI = wideband power = noise + serving cell power + interference power
RSSI is related to the other parameters through the following formula:

RSRQ=N*(RSRP/RSSI)
Where N is the number of Resource Blocks of the E-UTRA carrier RSSI
measurement bandwidth.
SINR:
SINR is the reference value used in the system simulation and can be defined:
 Wide band SINR
 SINR for a specific sub-carriers (or for a specific resource elements)

All measured over the same bandwidth!
RSSP vs RSRQ vs RSSI vs SINR
Below is a chart that shows what values are considered good and bad for the LTE
signal strength values:
CQI:
The Channel Quality Indicator (CQI) contains information sent from a UE to the
eNode-B to indicate a suitable downlink transmission data rate, i.e., a Modulation and
Coding Scheme (MCS) value. CQI is a 4-bit integer and is based on the observed signal-
to-interference-plus-noise ratio (SINR) at the UE. The CQI estimation process takes into
account the UE capability such as the number of antennas and the type of receiver used
for detection. This is important since for the same SINR value the MCS level that can be
supported by a UE depends on these various UE capabilities, which needs to be taken into
account in order for the eNode-B to select an optimum MCS level for the transmission.
The CQI reported values are used by the eNode-B for downlink scheduling and link
adaptation, which are important features of LTE.
In LTE, there are 15 different CQI values ranging from 1 to 15 and mapping
between CQI and modulation scheme, transport block size is defined as follows (36.213)

Table 21. CQI and Moduclation

BLER:
A Block Error Ratio is defined as the ratio of the number of erroneous blocks
received to the total number of blocks sent. An erroneous block is defined as a Transport
Block, the cyclic redundancy check (CRC) of which is wrong.
11.3.9 WCDMA (3G) DRIVE TEST PARAMETERS

RSCP (Received Signal Code Power)
The received power on one code measured on the Primary CPICH. Unit is dbm. It
shows signal strength of a cell. It Indicates Coverage.
RSSI (Received Signal Strength Indicator)
It is the wide-band received power within the relevant channel bandwidth. It is a
parameter in dbm that describes the total signal strength of a UTRA carrier frequency i.e.
signal strength of all cells of same frequency at a certain location.
Ec/No
It is a parameter in dB that describes the received energy per chip divided by the
power density in the band. Measurement shall be performed on the Primary CPICH.It
shows signal quality. Value of Ec/No>-15dB is considered good, between -15db and -18
dB is poor and less than -18dB is very poor.
Main reasons of poor Ec/Io are poor RSCP, missing neighbours, overshooting,
pilot pollution etc.
11.3.10 ACTIVE, MONITORED AND DETECTED SETS
Cells that the UE is monitoring are grouped in the UE into three mutually
exclusive categories:
Active Set: Active Set is defined as the set of cells the UE is simultaneously
connected to (i.e., the UTRA cells currently assigning a downlink DPCH to the UE
constitute the active set).
Monitored Set: Cells, which are not included in the active set, but are included in
the CELL_INFO_LIST belong to the Monitored Set i.e. shows probable candidate sectors
for handovers. If one of the active cells becomes weak, it is replaced by a candidate cell
having highest signal strength from monitored set.
Detected Set: Cells detected by the UE, which are neither in the
CELL_INFO_LIST nor in the active set belong to the Detected Set. All the missing
neighbors appear in detected set. These must not have high signal strengths otherwise
they will degrade the aggregate Ec/No & lead to call drops.
Pilot Pollution
When the number of strong cells exceeds the active set size, there is
―Pilot Pollution‖ in the area. Pilot pollution is the detection of many high power pilots as
compared to Best Serving Pilot that do not contribute to improve the signal strength. It
ultimately degrades the aggregate Ec/Io leading to call drop. All other strong signals
received when Active Set Size is full, act as interference which degrades the performance
of the system. Physical optimization should be done so that there should not be many
Pilots available at same spot with equally high signal strengths.
11.3.11 GSM (2G) DRIVE TEST PARAMETERS
 Rx level : Indicates received signal strength in dbm
 Rx Quality: Indicates Quality of voice, which is measured on the basis of
BER (Range 0-7 where value 0 denotes minimum BER.

 C/I: The carrier-over-interference ratio is the ratio between the signal

strength of the current serving cell and the signal strength of undesired
(interfering) signal components (Unit is dB)
 FER: Frame Erasure Rate it represents the percentage of frames being
dropped due to high number of bit errors in the frame. It is indication of
voice quality in network.
Figure 106: Screenshot of a Drive test window
11.4 SON ARCHITECTURE

The SON architecture defines the location of SON within the network. When
implemented at a high level in the network (OAM), it is called Network Management
System (NMS); while implementation at lower levels (network elements) like the eNBs is
called Element Management System (EMS). For self-configuration techniques of SON, a
self configuration subsystem is created in the OAM which handles the self configuration
process. For self optimization, the subsystem can be created in the OAM or the eNB or
both. Therefore, depending on the location of SON algorithms, SON architecture may be
described as being centralized, distributed or hybrid (a combination of centralized and
distributed).
Centralized SON Distributed SON
NMS Operator OSS NMS

Operator OSS
EMS Equipment vendor OSS Equipment vendor OSS EMS
Commands, Policies,
parameter Measure- high Reports
settings ments, level
KPIs KPIs
Hybrid SON
Operator
NMS OSS Commands
Reports SON related

Equipment vendor messages
EMS OSS
Commands,
parameter Measurements,
setting s, policies, KPIs, reports
high level KPIs
Commands
SON related
messages

Figure 107: SON Architecture

11.4.1 CENTRALIZED SON
In a centralized SON architecture, the algorithms are executed at the network

management level. Commands, requests and parameter settings data flow from the
network management level to the network elements, while measurement data and reports
flow in the opposite direction.
This is an example of the Network Management System (NMS) where the

algorithms are created and executed in the OAM . In this type of SON architecture, the
algorithms are present in just a few locations thereby making it simple and easy to
implement.
The main benefit of this approach is that the SON algorithms can take information
from all parts of the network into consideration. This means that it is possible to jointly
optimize parameters of all centralized SON functions such that the network becomes
more globally optimized, at least for slowly varying network characteristics. Also,
centralized solutions can be more robust against network instabilities caused by the
simultaneous operation of SON functions having conflicting goals. Since the control of
all SON functions is done centrally, they can easily be coordinated. Another advantage is
that multivendor and third party SON solutions are possible, since functionality can be
added at the network management level and not in the network elements where vendor
specific solutions are usually required.
Figure 108: Centralized SON Architecture

The main drawbacks of the centralized SON architecture are longer response
times, increased backbone traffic, and that it represents a single point of failure. The
longer response time limits how fast the network can adapt to changes and can even cause

network instabilities. The backbone traffic increase since measurement data have to be
sent from the network elements to the network management system and instructions must
be sent in the opposite direction. This traffic will increase as more cells are added to the
network. If there are many pico- and femto-cells this traffic will be very significant. Also,
the centralized processing power needed will be large.
11.4.2 DISTRIBUTED SON
In a distributed SON architecture, the SON algorithms are run in the network
nodes and the nodes exchange SON related messages directly with each other. This
architecture can make the SON functions much more dynamic than centralized SON
solutions, so that the network can adapt to changes much more quickly. It is also a
solution that scales very well as the number of cells in the network increases.
The main drawbacks are that the sum of all the optimizations done at cell level do
not necessarily result in optimum operation for the network as a whole and that it is more
difficult to ensure that network instabilities do not occur. Another drawback is that the
implementation of the SON algorithm in the network elements will be vendor specific, so
third party solutions will be difficult. Even if the algorithms themselves are executed in
the network elements, the network management system is usually able to control the
behavior of the SON function, for example, by setting the optimization criteria, receiving
periodic reports, and being able to turn it off if necessary.
An example of the EMS in which the algorithms are deployed and executed at the
eNBs is distributed SON. Therefore the SON automated processes may be said to be
present in many locations at the lower level of the architecture. Due to the magnitude of
deployment to be carried out caused by a large number of eNBs, the distributed SON
cannot support complex optimization algorithms.
Figure 109: Distributed SON Architecture

In order to fully benefit from this architecture type, work is being done towards
extending the X2 interface (interface between the eNBs). However, distributed SON
offers quick optimization/ deployment when concerned with one/two eNBs. An example
of this is in ANR and load balancing optimizations.

11.4.3 HYBRID SON
An architecture in which the optimization algorithms are executed in both OAM

and the eNBs is called Hybrid SON. Hybrid SON solution means that part of the SON
algorithm is run on the network management level and part is run in the network
elements. The solution represents an attempt to combine the advantages of centralized
and distributed SON solutions: centralized coordination of SON functions and the ability
to respond quickly to changes at the network element level.
The hybrid SON solves some of the problems posed by other architecture
alternatives. The simpler optimization processes are executed at the eNBs while the
complex ones are handled by the OAM; therefore, it supports various optimization
algorithms and also supports optimization between different vendors. However, the
hybrid SON is deployment intensive and requires several interface extensions.
Figure 110: Hybrid SON Architecture

Unfortunately, the drawbacks of both centralized and distributed SON are also
inherited. The SON related traffic in the backbone will be proportional to the number of
network elements in the network, which means that it might not scale well. The same
holds for the SON related processing required at the network management level. Also,
since parts of the SON algorithms are running in the network elements and the interface
between the centralized and distributed SON functions will be proprietary, third party
solutions will be difficult.
It should be noted that the term ―Hybrid SON‖ is not clearly defined and is used
differently by different vendors. Some vendors classify their solutions as ―hybrid‖ if the
network management system can control the SON function by setting main
parameters/policies, receiving reports and being able to turn it off if necessary.
11.5 CONCLUSION
RF Planning and Optimization plays a vital role in mobile radio network without
it is merely impossible to rollout and manage radio network.

E3-E4 Consumer Mobility CNMS Portal and Mobile NOC
12 CNMS PORTAL AND MOBILE NOC

After completion of this chapter participant will able to understand:
 CNMC Portal
 CNMC Connectivity
 CNMC Use
 CNMC Menus and there need.
 Mobile NOC
12.2 CNMC
It is Centralized Network Monitoring Center of BSNL which is connected to all
OMCRS across INDIA. It provides PAN INDIA BTS (Cell Wise) status, Voice and Data
Traffic, KPI Parameters (2G/3G/4G). It also Provide External Alarms, Lock Site Details.
12.2.1 CNMC CONNECTIVITY
The CNMC works on website www.cnmc.bsnl.co.in and is connected as per
below diagram
Figure 111: CNMC connectivity

12.2.2 CNMC ACCESS TECHNIQUES
Figure 112: CNMC ACCESS TECHNIQUES

12.2.3 CNMC FUNCTIONS
ALARMS
 REAL TIME STATUS OF BTS & SECTOR WISE ALL OVER INDIA
 Scripts runs continuously for every 15 minutes
 Drags Total down and Partial down alarms from all OMCRS over PAN
INDIA
QoS
 The QoS reports are also generated on daily basis which are automated
from 07:00 AM to 09:30 AM.
 The reports are fetched mostly from .csv/.txt files which are pulled from
OMCR‘s of all the vendors and backed up at 06:30 PM every day.
 The QoS parameters for 2G and 4G are as below. WIP for 3G QoS.
Locked sites
 This module shows the locked sites from all pan India circles.
 These sites can be locked due to many reasons like owner issue, hardware
failure issue etc. or maybe intentionally locked to get better overall
availability .
 The circles need to comply with the reasons which need to be updated in
the portal.
 This script runs only once for all vendors at midnight.
CGI reports
 Cell Global Identity (CGI) is a globally unique identifier for a Base
Transceiver Station in mobile phone networks.
 Consists of Mobile Country Code (MCC), Mobile Network Code (MNC),
Location Area Code (LAC) and Cell Identification (CI).
 It gives the above information for each sector/cell.
 We have approximately about 3.90L-4Lac cells.
 This information is fetched from the traffic reports once every month.
Many other useful parameters
 Revenue
 Gross Connection Growth
 MNP Ratio
 Voice Traffic
 Data Traffic

 Availability
 CDR
 CSSR
 Drive Test Conducted
 MTTR
 Halted Sites
 Low Traffic Sites
 6th Month Collection Efficiency
 Increase in Daily IN revenue
The reports can be checked online. Some real time snapshots of CNMC at
cnmc.bsnl.co.in are given below:-
Figure 113: CNMC Portal



12.3 MOBILE NOC

Mobile network operation center is LIVE 24 hours, all days. More calls are made
during day hours on a working day at a busy place in city centre whereas a much
more urgent call could be made in an isolated highway stretch at 2am. A site
outage at that time may cost someone a life. Hence, a mobile phone which is
attached almost every waking hour to oneself, is the most important utility that is
also a driver of business, a source of entertainment, could be a life saver and ……
a means of communication too! And we need to make it work reliably 24 x 7.
12.3.1 FIVE OBJECTIVES OF 24X7 NOC

 Establish a single establishment which has Visibility of all elements in the
network and watching it ALL THE TIME
 Knowledge of everything in the network and its surrounding that affacts
the network Tools and Capability to analyse and distil the data to bring out
what is important to act upon
 Expertise with confidence to advise the equipment in-charges on what is
wrong and needs to be done to correct
 Be a catalyst, bonding agent and an enabler among the mobile network
maintenance fraternity
 Thus, 24x7NoC shall in essence be a true mirror of everything in our
network, an agile expert to improve the network and a supporting hand for
all those who want to improve it.
12.3.2 MOBILE NOC FUNCTIONS
 Work Structure of NOC Pune
 Report preparation By NOC
 KPI PORTAL DEVELOPMENT
a) Work Structure of NOC Pune

Table 22. Work Structure of NOC Pune
Table 23. Work Structure of NOC Pune

b) Report preparation By NOC
Table 24. Reports

c) KPI PORTAL DEVELOPMENT
 Equipment of three venders are deployed in MH Circle , viz Alcatel/

Nokia/ ZTE.
 No NMS is available in BSNL Network
 There was No single entity was available with us which will provide a
integrated reports of all Venders.
 Hence in 2018 NOC has started in-house development of centralized
server which provides reports of all three venders on single platform.
 Over the period of two years the portal has become more mature and
different reports are available on portal in very professional manner.
 No CAPEX is done on this project as we have used the server which was
scraped.
 As development is continuous process we work on this server on daily
basis as per requirement is placed by Management.
12.4 FEATURES OF KPI SERVER
 Server development is entirely in House
 Firewall is used for security purpose.

 Reports are available Daily , TCBH and BBH

 Reports are available cell wise / Site wise / BSC wise/ RNC and SSA wise
 10 Mbps lease line is made available for seamless online availability
 Can be accessed via Mobile/ Laptop
Figure 119: KPI Server
Figure 120: Home Page KPI portal

This is containing all sub Tab and also the summaries SSA wise report of KPI
meeting for Last Day. The report contains cell wise BBH KPI, TCBH KPI and
DAY KPI.
a) The DAILY_KPI - gives yesterday KPI meeting summary for the whole
Network (2G/3G).
b) The HISTORY_KPI - gives summary of cells counts meeting KPI

parameter for last 10 days out of 15 days for 2G/3G network.
c) Traffic – It gives whole network traffic for last day as well as historical
traffic data.
d) BSC/RNC status.
e) VLR Report - It will display the Daily MSC VLR , PLMN VLR ,
roaming VLR, In-roam VLR, International Roam/In-roam VLR .
f) BSS_LOS:- Live Site failure report / bulk failure status.
g) Other - Different reports like Sleeping cells/ cell master/ping test etc.
12.5 CONCLUSION
CNMC and Mobile NOC are very important to manage the network properly


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E3-E4 Consumer Mobility Index

1 BASICS OF MOBILE COMMUNICATION .................................................... 2

2 MIGRATION TO MOBILE TECHNOLOGIES UPTO 5G ......................... 14

3 VARIOUS 3GPP RELEASES AND STANDARDS........................................ 26

4 VARIOUS PHASES OF BSNL CMTS TENDER ........................................... 53

5 BACKHAUL MEDIA FOR MOBILE RADIO NETWORK (OFC/ OFC

6 KPI REPORTS FOR 2G/3G/4G ....................................................................... 68

7 MOBILE SALES MANAGEMENT (BCCS, FRANCHISE MANAGEMENT,

8 3G MOBILE NETWORK ............................................................................... 110

9 4G MOBILE NETWORK ............................................................................... 128

10 CONCEPT OF SON ......................................................................................... 138

11 NETWORK OPTIMIZATION USING DTT REPORTS AND SON DATA

12 CNMS PORTAL AND MOBILE NOC.......................................................... 169

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1 BASICS OF MOBILE COMMUNICATION

Figure 1: Cell System

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1.3.2 CELL SECTORING

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 Seamless Network Architecture

First Design 1970 1980 1985 1990 2000

Implementation 1982 1991 1999 2002 2010?

Figure 4: Different Generations

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Figure 5: Basic Mobile Telephone Service Network

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Standard or Primary GSM 900 Band 1800 Band

Figure 6: GSM- Network Structure

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1.5.2 GSM NETWORK ELEMENTS

Figure 7: GSM- Architecture

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Equipment Identity Register (EIR)

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interests and past experience. As a result of performance analysis, if necessary, an alarm

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2 MIGRATION TO MOBILE TECHNOLOGIES UPTO 5G

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 Point-to-multipoint (PTM) services

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Figure 8: GPRS Architecture

Figure 9: GSM GPRS Architecture

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 Firewalls: used wherever a connection to an external network is required.

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Table 2. 3GPP Releases

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 Connection of mobile users to other mobile users or fixed users

ITU NOMENCLATURE COMMONLY KNOWN AS TECHNOLOGY

IMT-DS UTRA-FDD W-CDMA

IMT-SC UWV-136 TDMA

IMT-FT DECT TDMA + FDMA

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