Basic RAN Architecture and O&M
Basic RAN Architecture and O&M
Basic RAN Architecture and O&M
Objective
Understand Basic Architecture of Radio Network. Familiarize with the Interfaces of Radio Network and surrounded systems. Realize Basic components and their Functionality.
RAN Location:
The interfaces between the BSC and each NE in the GSM network are as follows:
Um Interface: the interface between the
BTS and MS Abis Interface: the interface between the BTS and BSC ATER Interface: the interface between the BSC and TC. A Interface: the interface between the TC and MSC or MGW Gb Interface: the Interface between the BSC and SGSN
BSS Functionality:
BSC Functionality:
Terrestrial Channel Management. Management of traffic channel. Paging Frequency Hopping control. BTS and MS power control Idle channel quality monitor Quality and field strength control of active channel. HO Control. Maintenance of BTS/TC/BSC. Interface with TC/OSS/MSC/BTS/SGSN.
BTS Functionality:
Timing BCCH and CCCH. Forward BTS/MS STS to BSC. Detect RACH from MS. Channel Coding/Decoding in Radio path. Encryption/Decryption on radio path. Perform FH. Modulation/Demodulation, Up/down conversation and power amplifying TX/RX RF signal. Report Idle Channel to BSC.
TC Functionality:
Converts 64-16KBPS and vice versa. Process CS services and perform the voice coding and decoding function Provides the Tandem Free Operation (TFO) function Provides the voice enhancement function
TRU Functionality:
Provides Um interface. Reallocates Traffic and control channels
PCU Functionality:
Process PS service. PDCH Channel management.
Switching Subsystem:
Provides intra-subrack Medium Access Control (MAC) switching Provides intra-subrack Time Division Multiplexing (TDM) switching Distributes clock signals to the service processing boards Provides inter-subrack switching Provides switching channels for traffic data Provides OM channels
O&M SubSystems:
Performing
the configuration management, performance management, fault management, security management, and loading management functions for the system
Clock Subsystem:
Provides synchronous timing signals for the system
BTS Components:
Physical Component System Module (TMU/ESMA) Transceiver Module (TRU/TRX/GTRU/DRFU) Combiner (Optional) (CDU/DDPU) Environment Monitoring Unit. (EMU) Logical Component: Cell TRX
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GPRS Interface:
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GPRS MS:
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PS Coding Scheme:
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Logical Channels:
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Logical Channels:
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Physical Channels:
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PS Domain:
Accessibility -UL/DL ASR -UL/DL TBF ASR -UL/DL TBF Congestion Rate Throughput -UL Data Throughput -DL Data Throughput Delay -Ping Delay -PDP Activation Delay -Attachment Delay -Cell Reselection Times Retain ability -UL/DL TBF Drop Rate Resource Utilization -UL PDCH Utilization Rate -DL PDCH Utilization Rate -PDCH Occupation Rate
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RAN FM:
Alarm Type:
Device Alarm (HW/ENV/COM) -Fan Box Alarm Transport Alarm -E1/T1 Loss of Signal Service Alarm (QoS/Running/SW/Signaling) -GSM Cell Out of Service Events
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RAN CM:
RAN Subsystem and Parameters configuration (BSC/BTS/TRX/Channels) BSC/BTS/TRX Software loading/updating BSC/BTS/TRX Maintenance. Authentication/Security/Log Management Centralized CM system (CME, LMT, OM Editor) MML/GUI capable LMT for configuration(Reflection/Huawei Web LMT) Powerful tools for effective/fast/easy configuration (CME) Intelligent CM tools (Consistency Check Tool/Rehome tool)
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RAN PM:
Counter, Object, Period (What/Who/When) All KPI is measured in BSC and sent to OSS. All the Counters are realized in different types (HW/RAN/TX) and are accumulated to generate predefined/Customized KPI.
Accessibility/Retain ability/Resource Utilization KPIs are measured in both CS/PS Domain to understand Network Experience.
More raw counters/KPIs can be correlated for analysis/RCA and Customer Problem Solving. But the Challenge is to correlate FM/PM/CM events!!!!
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RAN Parameters:
Network Identity Parameters (CGI/BSIC) Idle Mode Parameters (ATT, CCCH_Conf,BS_AG_BLKS, MFRAMES,T3212, Paging Times) Call Control Parameters (MaxRet,RLT,TX-Integer,ECSC,EC,MBR, Access Class, NCC Allowed, SACCH Multi-Frames, Max TA, T200 and N200, TCH immediate assignment, Direct Retry, ) Cell Selection and Reselection Parameters(RxLevel Acc Min,CBA,CBQ,CRH,TO,PT,PI) Other Parameters
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RAN Parameters:
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RAN Features:
Features are Extended license controlled parameters used for User Benefit
BSS Paging Coordination DFCA OSC DTM Repeated SACCH/FACCH Call Reestablishment SRA eMLPP
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Questions/Answer
??Questions/Answer??
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