VISVESWARAIAH TECHNOLOGICAL UNIVERSITY.

BELGAUM (KARNATAKA)

TECHNICAL SEMINAR

ON
“4G Wireless System”

BY
Manu.R (1ki06te408)

DEPT OF TELECOMMUNICATION ENGINEERING.

KALPATARU INSTITUTE OF TECHNOLOGY

Tiptur-572202
2009-2010
4G WIRELES SYETEM

mobile service, but also will

support the fixed wireless
networks. This paper presents
ABSTRACT:- an overall vision of the 4G
The approaching 4G features, framework, and
(fourth generation) mobile integration of mobile
communication systems are communication. The features of
projected to solve still- 4G systems might be
remaining problems of 3G (third summarized with one word—
generation) systems and to integration. The 4G systems are
provide a wide variety of new about seamlessly integrating
services, from high-quality terminals, networks, and
voice to high-definition video to applications to satisfy increasing
high-data-rate wireless user demands. The continuous
channels. The term 4G is used expansion of mobile
broadly to include several types communication and wireless
of broadband wireless access networks shows evidence of
communication systems, not exceptional growth in the areas
only cellular telephone systems. of mobile subscriber, wireless
One of the terms used to network access, mobile services,
describe 4G is MAGIC— and applications.
Mobile multimedia, anytime
Introduction:-
anywhere, Global mobility
support, integrated wireless Consumers demand
solution, and customized more from their technology.
personal service. As a promise Whether it be a television,
for the future, 4G systems, that cellular phone, or refrigerator,
is, cellular broadband wireless the latest technology purchase
access systems have been must have new features. With
attracting much interest in the the advent of the Internet, the
mobile communication arena. most-wanted feature is better,
The 4G systems not only will faster access to information.
support the next generation of Cellular subscribers pay extra

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on top of their basic bills for To support such a powerful

such features as instant system, we need pervasive,
messaging, stock quotes, and high-speed wireless
even Internet access right on connectivity.
their phones. But that is far
A number of
from the limit of features;
technologies currently exist to
manufacturers entice customers
provide users with high-speed
to buy new phones with photo
digital wireless connectivity;
and even video capability. It is
Bluetooth and 802.11 are
no longer a quantum leap to
examples. These two standards
envision a time when access to
provide very high speed
all necessary information the
network connections over short
power of a personal computer ,
distances, typically in the tens
sits in the palm of one’s hand.
of meters. Meanwhile, cellular
providers seek to increase speed In a fourth-generation
on their long-range wireless wireless system, cellular
networks. The goal is the same: providers have the opportunity
long-range, high-speed wireless, to offer data access to a wide
which for the purposes of this variety of devices. The cellular
report will be called 4G, for network would become a data
fourth-generation wireless network on which cellular
system. Such a system does not phones could operate-as well as
yet exist, nor will it exist in any other data device. Sending
today’s market without data over the cell phone network
standardization. Fourth- is a lucrative business. In the
generation wireless needs to be information age, access to data
standardized throughout the is the “killer app” that drives the
world due to its enticing market. The most telling
advantages to both users and example is growth of the
providers. Internet over the last 10 years.
Economic Impact:- Wireless networks provide a

Advantages of 4G:- unique twist to this product:

mobility. This concept is

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already beginning a revolution wireless is not already available.

in wireless networking, with After all, wireless providers are
instant access to the Internet already moving in the direction
from anywhere. of expanding the bandwidth of
Problems with the their cellular networks. Almost

Current System all of the major cell phone

networks already provide
One may then wonder
why ubiquitous, high-speed
data services beyond that different protocols that allow for
offered in standard cell phones, faster access speeds and more
as illustrated in Table 1. efficient transfers. These are
Unfortunately, the current collectively referred to as third
cellular network does not have generation, or 3G, services.
the available bandwidth However, the way in which the
necessary to handle data companies are developing their
services well. Not only is data networks is problematic — all
transfer slow - at the speed of are currently proceeding in
analog modems - but the different directions with their
bandwidth that is available is technology improvements.
not allocated efficiently for Figure 1 illustrates the different
data. Data transfer tends to technologies that are currently
come in bursts rather than in the in use, and which technologies
constant stream of voice data. the providers plan to use.
Cellular providers are Although most
continuing to upgrade their technologies are similar, they
networks in order to meet this are not all using the same
higher demand by switching to
protocol. In addition, 3G voice. Thus, they are inefficient
systems still have inherent with their use of the available
flaws. They are not well- spectrum bandwidth. A data-
designed for data; they are centered protocol is needed. If
improvements on a protocol that one were to create two identical
was originally designed for marketplaces in which cellular

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providers used 3G and 4G like the cellular industry can be

respectively, the improvements modeled as a game, as in Table
in 4G would be easy to see. 2.
Speaking on the topic of 3G, There are three basic
one of the worlds leading paths the game can take:
authorities on mobile Nobody makes the conversion
communications, William C.Y. to 4G All end up upgrading to
Lee, states that 3G would be “a 2.5G and 3G services. The
patched up system that could be upgrades are incremental, and
inefficient”, and it would be don’t require a complete
best if the industry would reworking of the system, so they
leapfrog over 3G wireless are fairly cheap — the
technologies, and prepare for equipment required is already
4G (Christian). 4G protocols developed and in mass
use spectrum up to 3 times as production in other places in the
efficiently as 3G systems, have world.
better ways of handling Everyone makes the
dynamic load changes (such as conversion to 4G The
additional cellular users equipment and technology
entering a particular cell), and needed for 4G will be cheap,
create more bandwidth than 3G because of all of the cellular
systems. Most importantly, manufacturers investing in it.
fourth-generation systems will Cellular providers will market
draw more users by using additional services to its
standard network protocols, customers.
which will be discussed later, to Some of the players make the
connect to the Internet. This will conversion to 4G Because not
allow simple and transparent all of the players have chosen
connectivity. 4G, the equipment will be more
Barriers to Progress:- expensive than the second

Why are cellular scenario. Even though

providers not moving to 4G converters will be able to sell

instead of 3G? A market place more services to their

customers, it will not be enough
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to cover the higher costs of provider has incentive to move

converting to 4G. to 4G unless all providers move
Therefore, if a player to 4G. An outside agent — the
chooses the 4G strategy, but national government — must
nobody else follows suit, that standardize on 4G as the
player will be at a significant wireless standard
disadvantage. No cellular
for the communication. Of common concern is the
course, legitimate concerns can similarity of this proposal to the
be posed to the idea of forced introduction of HDTV in
implementing 4G nationwide. A the US, which has (thus far)
failed miserably. There are two part of their business plan. Our
key differences, however, proposal is simply choosing a
between 4G and HDTV. The direction for their growth.
first is the nature of the service An often overlooked
providers. There are many small area of financial liability for
television broadcasters in rural cellular providers is in the area
areas whose cost of conversion of information security.
would be as much as 15years of Providers could lose money
revenue. The cellular industry, through fraudulent use of the
however, does not have this cellular system or unauthorized
problem. The players are multi- disclosure of user information
billion dollar companies, who over the airwaves. Both of these
already have enough capital; cases could be caused by an
continual network upgrades are insecure wireless system.

Table 1: Cellular Providers and Services

Cellular provider Features
Sprint e-mail, pictures, games, music, Internet
AT&T e-mail, games, music
Verizon e-mail, pictures, games, music, Internet
Nextel e-mail, pictures, games, music, Internet
T-Mobile (VoiceStream) e-mail, pictures, games, music, Internet

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Cingular text messaging

Figure 1: Cellular Provider System Upgrades

Table 2: The Cellular Industry as a Game
Players The cellular providers
Strategies Upgrade to 4G, or make small incremental changes
Outcome This can be simplified to the cost of conversion. The cost
of conversion (because of economies of scale), depends on
the number of companies that actually convert to 4G —
networking equipment and wireless access equipment will
get cheaper as more of them are produced and bought by
the cellular providers.

Current transmission technologies: time-

division multiple access
Technology:- (TDMA) or code-division
Most modern cellular multiple access (CDMA)
phones are based on one of two

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(Prizeman 2000, 40).These two difficult by digitally encoding

technologies are collectively the voice data and compressing
referred to as second- it, then splitting up the resulting
generation, or 2G. Both systems data into chunks upon
make eavesdropping more transmission.
negative side effect of wasting
bandwidth and capacity on
.TDMA:- devices that have nothing to

TDMA, or Time send (Leon-Garcia and Widjaja

Division Multiple Access, is a 2000).

technique for dividing the time One optimization that

domain up into sub channels for makes TDMA much more

use by multiple devices. Each efficient is the addition of a

device gets a single time slot in registration period at the

a procession of devices on the beginning of the frame. During

network, as seen in Figure 3. this period, each device

During that particular time slot, indicates how much data it has

one device is allowed to utilize to send. Through this

the entire bandwidth of the registration period, devices with

spectrum, and every other nothing to send waste no time

device is in the quiescent state. by having a timeslot allocated to

The time is divided into them, and devices with lots of

frames in which each device on pending data can have extra

the network gets one timeslot. time with which to send it. This

There are n timeslots in each is called ETDMA (Extended

frame, one each for n devices on TDMA) and can increase the

the network. In practice,every efficiency of TDMA to ten

device gets a timeslot in every times the capacity of the

frame. This makes the frame original analog cellular phone

setup simpler and more efficient network.

because there is no time wasted The benefit of using

on setting up the order of TDMA with this optimization

transmission. This has the for network access comes when

data is “bur sty.” That means, at
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an arbitrary time, it is not and the amount of background

possible to predict the rate or noise are constantly varying.
amount of pending data from a Thus, for this type of data, very
particular host. This type of data little capacity is wasted by
is seen often in voice excessive allocation.
transmission, where the rate of
speech, the volume of speech,
Figure 3: Time Division Multiple Access

CDMA:- unique code for the phone.

CDMA, or Code Thus, one data bit is

Division Multiple Access, transformed into a sequence of

allows every device in a cell to bits of the same length as the

transmit over the entire code for the mobile phone. This

bandwidth at all times. Each makes it possible to combine

mobile device has a unique and with other signals on the same

orthogonal code that is used to frequency range and still

encode and recover the signal recover the original signal from

(Leon-Garcia and Widjaja an arbitrary mobile phone as

2000). The mobile phone long as the code for that phone

digitizes the voice data as it is is known. Once encoded, the

received, and encodes the data data is modulated for

with the unique code for that transmission over the bandwidth

phone. This is accomplished by allocated for that transmission.

taking each bit of the signal and A block diagram of the process

multiplying it by all bits in the is shown in Figure 4.

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Figure 4: Sending Data using Code Division Multiple Access

Figure 5: Receiving Data using Code Division

Multiple Access

Figure 6: UWB Spectrum Usage

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The process for receiving a require higher data rates than

signal is shown in Figure 5. 2G can handle. A new system is
Once the signal is demodulated, needed that merges voice and
acorrelator and integrator pair data into the same digital
recovers the signal based on the stream, conserving bandwidth to
unique code from the cellular enable fast data access. By
phone. The correlator recovers using advanced hardware and
the original encoded signal for software at both ends of the
the device, and the integrator transmission, 4G is the answer
transforms the recovered signal to this problem.
into the actual data stream. 4G Hardware:-
CDMA has been
Ultra Wide Band
patented in the United States by
Networks
Qualcomm, making it more
Ultra Wideband
expensive to implement due to
technology, or UWB, is an
royalty fees. This has been a
advanced transmission
factor for cellular phone
technology that can be used in
providers when choosing which
the implementation of a 4G
system to implement.
network. The secret to UWB is
By keeping security in
that it is typically detected as
mind while designing the new
noise. This highly specific kind
system, the creators of 2G
of noise does not cause
wireless were able to produce a
interference with current radio
usable system that is still in use
frequency devices, but can be
today. Unfortunately, 2G
decoded by another device that
technology is beginning to feel
recognizes UWB and can
its age. Consumers now demand
reassemble it back into a
more features, which in turn
signal. Since the signal is currently in use by other radio
disguised as noise, it can use frequency devices (Cravotta ).
any part of the frequency An Ultra Wideband
spectrum, which means that it device works by emitting a
can use frequencies that are series of short, low powered
electrical pulses that are not
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directed at one particular signal, special antennas are

frequency but rather are spread needed to tune and aim the
across the entire spectrum signal.
(Butcher ). As seen in Figure 6, Smart Antennas:
Ultra Wideband uses a Multiple “smart
frequency of between 3.1 to antennas” can be employed to
10.6 GHz. help find, tune, and turn up
The pulse can be called signal information. Since the
“shaped noise” because it is not antennas can both “listen” and
flat, but curves across the “talk,” a smart antenna can send
spectrum. On the other hand, signals back in the same
actual noise would look the direction that they came from.
same across a range of This means that the antenna
frequencies it has no shape. For system cannot only hear many
this reason, regular noise that times louder, but can also
may have the same frequency as respond more loudly and
the pulse itself does not cancel directly as well (ArrayComm
out the pulse. Interference 2003).
would have to spread across the There are two
spectrum uniformly to obscure types of smart antennas:
the pulse. Switched Beam Antennas (as
UWB provides greater seen in Figure 7) have fixed
bandwidth — as much as 60 beams of transmission, and can
megabits per second, which is 6 switch from one predefined
times faster than today’s beam to another when the user
wireless networks. It also uses with the phone moves
significantly less power, since it throughout the sector
transmits pulses instead of a Figure 7: Switched Beam
continuous signal. UWB uses Antenna
all frequencies from high to
low, thereby passing through
objects like the sea or layers of
rock. Nevertheless, because of
the weakness of the UWB
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Adaptive Array Antennas (as • Reuse available

seen in Figure 8) represent the spectrum
most advanced smart antenna • Increase bandwidth
approach to date using a variety • Lengthen battery life of
of new signal processing wireless devices.
algorithms to locate and track Although UWB and
the user, minimize interference, smart antenna technology may
and maximize intended signal play a large role in a 4G system,
reception advanced software will be
(ArrayComm 2003). needed to process data on both
the sending and receiving side.
Thissoftware should be flexible,
as the future wireless world will
likely be a heterogeneous mix of
technologies.

Figure 7: Switched Beam 4G Software:-

Antenna 4G will likely become a
unification of different wireless
Smart antennas can thereby: networks, including wireless
• Optimize available LAN technologies (e.g. IEEE
power 802.11), public cellular
• Increase base station networks (2.5G, 3G), and even
range and coverage personal area networks. Under

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this umbrella, 4G needs to any radio or frequency standard

support a wide range of mobile through the use of software. For
devices that can roam across example, if one was a subscriber
different types of networks of Sprint and moved into an
(Cefriel ). These devices would area where Sprint did not have
have to support different service, but Cingular did, the
networks, meaning that one phone would automatically
device would have to have the switch from operating on a
capability of working on CDMA frequency to a TDMA
different networks. One solution frequency. In addition, if a new
to this “multi-network standard were to be created, the
functional device” is a software phone would be able to support
defined radio. that new standard with a simple
Software Defined Radio software update. With current

A software defined radio phones, this is impossible.

is one that can be configured to

Figure 9: Packet with 896-bit payload

A software defined radio in the outside of the user’s home
context of 4G would be able to network.
work on different broadband A software defined
networks and would be able to radio’s best advantage is its
transfer to another network great flexibility to be
seamlessly while traveling programmed for emerging

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wireless standards. It can be Currently, the Internet

dynamically updated with new uses the Internet Protocol
software without any changes in version 4 (IPv4) to locate
hardware and infrastructure. devices. IPv4 uses an address in
Roaming can be an issue with the format of xxx.xxx.xxx.xxx
different standards, but with a where each set of three digits
software defined radio, users can range from 0 to 255 (e.g
can just download the interface 130.207.44.251). Though
upon entering new territory, or combinations are reserved, but
the software could just this address format allows for
download automatically (Wang approximately 4.2 billion
2001). Of course, in order to be unique addresses. Almost all IP
able to download software at addresses using IPv4 have been
any location, the data must be assigned, and given the number
formatted to some standard. of new devices being connected
This is the job of the packet to the Internet every day, space
layer, which will split the data is running out. As people begin
into small “packets.” to connect refrigerators, cars,
Implementation of and phones to the Internet, a

Packets larger address space will be

needed.
Current System: IPv4

Recommended System: IPv6 makes up one eighth of the

The next generation address. An example of this
addressing system uses the is:FEDC:BA98:7654:3210:FED
Internet Protocol version 6 C:BA98:7654:3210 (The
(IPv6) to locate devices. IPv6 Internet Engineering Task Force
has a much larger address space. Network Working Group ).
Its addresses take the form Using this address format, there
x:x:x:x:x:x:x:x where each x is is room for approximately 3.40
the hexadecimal value that * 1038 unique addresses. This is

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approximately 8.05*1028 times over any equipment that

as large as the IPv4 address supports packet-based
space and should have room for communication and they receive
all wired and wireless devices, all of the error correction and
as well as room for all of the other benefits that packets
foreseeable expansion in several receive. There are many
lifetimes. There are enough interconnects between the data
addresses for every phone to Internet and the phone network,
have a unique address. Thus, so not only can VoIP customers
phone in the future can use communicate with each other,
VoIP over the Internet instead they can also communicate with
of continuing to use their users of the old telephone
existing network.Voice over IP system.
(VoIP) One other thing that
Voice over IP is the VoIP allows is slow transition
current standard for voice from direct, connection based
communication over data communication to VoIP
networks. Several standards communication. Backbones can
already exist for VoIP, the be replaced, allowing old-style
primary one being International lephone users to connect to their
Multimedia telecommunications central office (CO) the same
Consortium standard H.323. way. However, the CO will then
VoIP is already in use in many connect to an IPv6 Internet
offices to replace PBX-based backbone, which will then
systems and by several connect to the destination CO.
companies that offer cheap long To the end user, there will not
distance phone calls over the seem to be any difference, but
Internet, such as Net2Phone and the communication will occur
Go2Call. VoIP allows for primarily over a packet-based
flexibility the same way that system, yielding all of the
data packets do; as far as the benefits of packets, outside of
network is concerned, VoIP the short connections between
packets are the same as any either end of the communication
other packet. They can travel and their CO.
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Of course, in order to keep In reality, however, the

curious users from listening in usage of different encryption
by “sniffing,” all data, including schemes depends on many
voice, should be encrypted factors, including network data
while in transit. flow design. Thus, it is

Encryption:- important that the encryption

Two method be able to change when

encryption/decryption other determining factors

techniques are commonly used: change. Al-Muhtadi, Mickunas,

asymmetric and symmetric and Campbell of University of

encryption. Symmetric Illinois at Urbana-Champaign

encryption is the more showed great foresight in

traditional form, where both admitting that “existing security

sides agree on asystem of schemes in 2G and 3G systems

encrypting and decrypting are inadequate, since there is

messages — the reverse of the greater demand to provide a

encryption algorithm is the more flexible, reconfigurable,

decryption algorithm. Modern and scalable security

symmetric encryption mechanism as fast as mobile

algorithms are generic and use a hosts are evolving into full-

key to vary the algorithm. Thus, fledged IP-enabled devices”

two sides can settle on a specific (Al-Muhtadi, Mickunas, and

key to use for their Campbell 2002, 60).

communications. The problem Unfortunately, IPv6 can

then is the key transportation only protect data in

problem: How do both sides get transmission. Individual

the key without a third party applications may contain flaws

intercepting it? If an in the processing of data,

unauthorized user receives the thereby opening security holes.

key, then he too can decrypt the These holes may be remotely

messages. exploited, allowing the security

of the entire mobile device to be
compromised. Thus, any
Flexibility:-
wireless device should provide a
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process for updating the to Trojans or become corrupt

application software as security with viruses. Therefore, any
holes are discovered and fixed. new wireless handheld device
Anti-Virus:- should incorporate antivirus

As wireless devices software. This software should

become more powerful, they scan all e-mail and files entering

will begin to exhibit the same through any port (e.g. Internet,

security weaknesses as any beaming, or synchronizing),

other computer. For example, prompting the user to remove

wireless devices may fall victim suspicious software in the

process. The antivirus software

should also allow secure,
remote updates of
the scanning software in order infrastructure to provide the
to keep up with the latest latest features as incentives,
viruses (NIST, U.S. Dept. of often turning to various 3G
Commerce , 5-34). solutions. Unfortunately, this

Conclusion:- will only serve to bewilder

customers in an already
Consumers demand that
confusing market.
software and hardware be user-
Customers want the
friendly and perform well.
features delivered to them,
Indeed, itseems part of our
simple and straightforward.
culture that customers expect
Wireless providers want to
the highest quality and the
make money in a cutthroat
greatest features from what they
industry. If the U.S. government
buy. The cellular telephone
wants to help, the best way to
industry, which now includes a
help all parties is to enforce 4G
myriad of wireless devices, is
as the next wireless standard.
no exception.
The software that consumers
Meanwhile, competition
desire is already in wide use.
in the industry is heating up.
The transmission hardware to
Providers are slashing prices
take it wireless is ready to go.
while scrambling for the needed

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And we have the security 1. B. G. Evans and K. Baughan,

practices to make sure it all "Visions of 4G," Electronics and

works safely. The government Communication Engineering

Journal, Dec. 2002.
need only push in the right
direction; the FCC need only 2. H. Huomo, Nokia, "Fourth
standardize 4G in order to make Generation Mobile," presented at
the transition economically ACTS Mobile Summit99,

viable for all involved. Sorrento, Italy, June 1999.

This is a need that Bibliography

demands a solution. Today’s
wired society is going wireless,
and it 1. www.wikipedia.com
2. www.google.com
has a problem. 4G is the answer.
REFERENCES:-

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