Alcatel GSM

BSS System Description

BSS Document

Concept Guide

Release B10

3BK 21222 AAAA TQZZA Ed.01

Status RELEASED

Short title System Description

All rights reserved. Passing on and copying of this document, useand communication of its contents not permitted without writtenauthorization from Alcatel.

BLANK PAGE BREAK

2 / 306 3BK 21222 AAAA TQZZA Ed.01

Contents

ContentsPreface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 131 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15

1.1 Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 161.1.1 Evolium Radio Solutions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 171.1.2 Extended GSM Band (E-GSM) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 171.1.3 GSM 850 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 171.1.4 Frequency Band Configurations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 181.1.5 GPRS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18

1.2 BSS Functions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 181.2.1 Call Set Up . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 191.2.2 Call Handling . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 201.2.3 Call Release . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 201.2.4 Operations & Maintenance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21

1.3 BSS Components . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 211.3.1 Base Station Controller . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 221.3.2 Base Transceiver Station . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 231.3.3 Transcoder And Transmission Function . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 261.3.4 The Multi-BSS Fast Packet Server . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27

1.4 Extended GSM . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 301.4.1 E-GSM Mobile Station Recognition . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 301.4.2 E-GSM Management After Initial Determination . . . . . . . . . . . . . . . . . . . . . . . . . . . 311.4.3 E-GSM Determination at Handover . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 311.4.4 TCH Allocation for E-GSM and P-GSM Mobile Stations . . . . . . . . . . . . . . . . . . . . 32

1.5 External Components . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 331.5.1 Network Subsystem . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 341.5.2 Mobile Stations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 351.5.3 Phase 2 Mobile Support in a Phase 1 Infrastructure . . . . . . . . . . . . . . . . . . . . . . . 391.5.4 Operations and Maintenance Center-Radio . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39

1.6 Network Management . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 401.6.1 Telecommunications Management Network . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 401.6.2 Q3 Interface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41

1.7 BSS Telecommunications Layers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 421.7.1 Call Management Sub-layer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 421.7.2 Mobility Management Sub-layer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 421.7.3 Radio Resource Management Sub-layer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 431.7.4 The A Interface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 441.7.5 The Ater Interface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 451.7.6 The Abis Interface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 451.7.7 HSL Links . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 461.7.8 Satellite Links . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 461.7.9 The Air Interface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 471.7.10 System Information Messages . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 521.7.11 Dynamic SDCCH Allocation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 56

1.8 2G and 3G Interworking . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 571.8.1 2G and 3G Cells . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 571.8.2 2G to 3G Handover . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 581.8.3 2G to 3G Reselection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 59

2 GPRS in the BSS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 612.1 Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 62

2.1.1 Packet Switching . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 622.1.2 GPRS Elements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 64

2.2 GPRS Channels and System Information Messages . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 672.2.1 Logical Channels . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 67

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2.2.2 Virtual Channels . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 672.2.3 System Information Messages . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 68

2.3 GPRS Interfaces . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 692.3.1 The Gb Interface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 692.3.2 The BSCGP Interface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 702.3.3 The GCH Interface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 712.3.4 Specific LCS Interfaces . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 72

2.4 GPRS Network Functions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 732.4.1 MAC and RLC Functions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 732.4.2 Temporary Block Flow . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 732.4.3 Mobility Management . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 732.4.4 Enhanced Packet Cell Reselection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 752.4.5 Paging . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 792.4.6 Radio Power Control and Radio Link Measurement . . . . . . . . . . . . . . . . . . . . . . . . 80

2.5 Resource Management . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 802.5.1 Time Slot Allocation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 812.5.2 Autonomous Packet Resource Allocation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 822.5.3 Packet Flow Context . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 842.5.4 Dynamic Abis Allocation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 852.5.5 Enhanced Transmission Resource Management . . . . . . . . . . . . . . . . . . . . . . . . . . 882.5.6 Frequency Hopping . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 882.5.7 PCM Link Sharing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 892.5.8 TBF Resource Re-allocation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 89

2.6 Traffic Load Management . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 912.6.1 Smooth PDCH Traffic Adaption to Cell Load Variation . . . . . . . . . . . . . . . . . . . . . . 912.6.2 Congestion Control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 922.6.3 M-EGCH Statistical Multiplexing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 922.6.4 GPRS Overload Control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 92

2.7 Data Transmission . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 932.7.1 GPRS Attach . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 932.7.2 Packet Data Protocol Context Activation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 942.7.3 Data Transfer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 972.7.4 Packet Data Protocol Context De-activation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1062.7.5 GPRS Suspend . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1092.7.6 GPRS Resume . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1102.7.7 GPRS Detach . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 112

2.8 Location Services (LCS) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1142.8.1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1142.8.2 Logical Architecture . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1152.8.3 LCS Positioning Methods . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1162.8.4 LCS Scenario in Circuit-Switched Domain . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1172.8.5 Physical Implementation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1172.8.6 SMLC Functions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1182.8.7 BSS and Cell Configuration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1182.8.8 LCS O&M . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 119

2.9 High Speed Data Service (HSDS) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1202.9.1 HSDS Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1202.9.2 GPRS CS3/CS4 and EGPRS Protocol . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1212.9.3 Transmission Handling . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1232.9.4 Cell/GPU Mapping Modification . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 126

3 Call Set Up . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1273.1 Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 128

3.1.1 Call Types . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1283.1.2 Call Set Up Phases . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 129

3.2 Mobile-Originated Call . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1303.2.1 Radio and Link Establishment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1303.2.2 Authentication and Ciphering . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 139

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3.2.3 Normal Assignment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1403.3 Mobile-Terminated Call . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 146

3.3.1 Radio and Link Establishment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1473.3.2 Authentication and Ciphering . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1473.3.3 Normal Assignment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1483.3.4 Off Air Call Set Up . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1493.3.5 IMSI Attach-Detach . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 149

3.4 Paging . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1503.4.1 Paging Control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1523.4.2 Discontinuous Reception . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 155

3.5 Congestion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1553.5.1 Queueing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1553.5.2 In-queue . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1563.5.3 Pre-emption . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 158

3.6 Classmark Handling . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1593.6.1 Classmark IE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1603.6.2 Classmark Updating . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1623.6.3 Location Updating with Classmark Procedure . . . . . . . . . . . . . . . . . . . . . . . . . . . . 163

3.7 Authentication . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1653.7.1 IMSI/TMSI . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1653.7.2 Authentication Procedure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 166

3.8 Ciphering . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1673.8.1 Mobile Station Ciphering Capability . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1673.8.2 BSS Ciphering Capability . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1683.8.3 Ciphering Keys . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1683.8.4 Ciphering Process . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 168

3.9 Tandem Free Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1713.9.1 TFO Process . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1723.9.2 TFO Functional Architecture . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1733.9.3 TFO Optimization and Management . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 174

4 Call Handling . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1754.1 Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1764.2 In-Call Modification . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 177

4.2.1 In-Call Modification Procedure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1784.2.2 Circuit-Switched Group 3 Fax Data Rate Change . . . . . . . . . . . . . . . . . . . . . . . . . 1794.2.3 Error Handling . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 179

4.3 Frequency Hopping . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1804.3.1 Baseband Frequency Hopping . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1814.3.2 Synthesized Frequency Hopping . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 182

4.4 Speech Transmission . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1834.4.1 Continuous Transmission . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1834.4.2 Discontinuous Transmission . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1834.4.3 Voice Activity Detection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1844.4.4 BSS Discontinuous Transmission Towards Mobile Station . . . . . . . . . . . . . . . . . 1844.4.5 Mobile Station Discontinuous Transmission Towards BSS . . . . . . . . . . . . . . . . . 186

4.5 Radio Power Control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1884.5.1 BTS Radio Power Control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1884.5.2 Mobile Station Radio Power Control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1884.5.3 Radio Link Measurements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1894.5.4 Power Control Decision and Handover . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1904.5.5 Change Power Levels . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 192

4.6 Handover . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1934.6.1 Principal Handover Types . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1944.6.2 Radio Measurements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1964.6.3 Handover Detection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1974.6.4 Target Cell Evaluation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2034.6.5 Synchronous and Asynchronous Handover . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 205

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4.6.6 Circuit-Switched Telecom Handovers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2094.7 Overload Control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 211

4.7.1 BTS Overload . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2114.7.2 BSC Overload . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 212

4.8 Call Re-establishment by the Mobile Station . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2145 Call Release . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 215

5.1 Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2165.2 Call Release Procedures in Normal Service . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 217

5.2.1 Normal Release . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2175.2.2 Calls Terminated Following a Channel Change . . . . . . . . . . . . . . . . . . . . . . . . . . . 223

5.3 Call Release - Special Cases . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2245.3.1 Call Release Following Reset . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2245.3.2 BSC-Initiated Release . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2265.3.3 BSC-Initiated SCCP Release . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2285.3.4 BTS-Initiated Call Release . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2285.3.5 Mobile Station-Initiated Call Release . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2315.3.6 Remote Transcoder Alarms . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 232

5.4 Preserve Call Feature . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2335.4.1 Normal Release . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2335.4.2 Abnormal Release . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 234

6 Handling User Traffic Across the BSS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2356.1 Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2366.2 Speech . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 236

6.2.1 Analog . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2376.2.2 Interleaving and Forward Error Correction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2376.2.3 Speech Data Bursts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2376.2.4 Digital Speech . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2386.2.5 Digital 64 kbit/s A-law Encoded Speech . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2386.2.6 Enhanced Full-Rate . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2396.2.7 Half-Rate . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2406.2.8 Adaptive Multiple Rate . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2416.2.9 Channel Mode Adaptation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2446.2.10 VGCS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 245

6.3 Circuit-Switched Data Modes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2466.3.1 Transparent Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2466.3.2 Non-Transparent Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 248

6.4 Short Message Service - Cell Broadcast . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2496.4.1 SMS-CB Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2496.4.2 Phase 2+ Enhancements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 250

6.5 Support of Localized Service Area . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2516.6 PLMN Interworking . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 252

7 Cell Environments . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2537.1 Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 254

7.1.1 Rural and Coastal Coverage . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2567.1.2 Urban Coverage . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 256

7.2 Concentric Cell . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2567.3 Sectored Site . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2577.4 Extended Cell . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 258

7.4.1 Standard Extended Cell . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2597.4.2 Enlarged Extended Cell . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2597.4.3 PS in Extended Cell . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 260

7.5 Umbrella Cell . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2617.5.1 Mini Cell . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2617.5.2 Microcell . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2627.5.3 Indoor Cell . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 265

7.6 Cell Shared by Two BTS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 266

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7.7 Unbalancing TRX Output Power per BTS sector . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2678 Operations & Maintenance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 269

8.1 Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2708.1.1 Subsystem O&M Functions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2718.1.2 System O&M Functions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 272

8.2 O&M Control - Subsystems . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2738.2.1 LMTs and the IMT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2738.2.2 OML Auto-Detection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2748.2.3 Managed Objects . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2748.2.4 Security Blocks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 274

8.3 O&M Control - The OMC-R . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2758.3.1 Multiple Human-Machine Interface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2758.3.2 ACO . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2768.3.3 Connection From BSC to OMC-R . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2778.3.4 Electronic Documentation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 278

8.4 Configuration Management . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2798.4.1 Hardware Configuration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2808.4.2 Logical Configuration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2808.4.3 Default Parameter Customization . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2818.4.4 Software Configuration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2818.4.5 Auto-Identification . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2818.4.6 OML Auto-Detection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2838.4.7 Network Element Provisioning . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 284

8.5 Fault Management - Alarms . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2858.5.1 Alarm Generation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2878.5.2 Alarm Functions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2878.5.3 BSC Alarms . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2898.5.4 BTS Alarms . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2938.5.5 Alarms Detected by the TSC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2958.5.6 MFS Alarms . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2958.5.7 Recovery Example: Carrier Unit Failures with BCCH . . . . . . . . . . . . . . . . . . . . . . 2968.5.8 Automatic Power-Down . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2998.5.9 BSC Alerter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 299

8.6 Performance Management . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3008.6.1 Traces . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3008.6.2 Performance Monitoring . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3018.6.3 Radio Measurements Statistics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3018.6.4 Results Analysis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 303

8.7 Audits . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3048.7.1 Audit Types . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3048.7.2 Audit Flow . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 305

8.8 Remote Inventory . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 306

3BK 21222 AAAA TQZZA Ed.01 7 / 306

Figures

FiguresFigure 1: BSS in the PLMN . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16Figure 2: Antenna Diversity on G1 and G2 BTS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24Figure 3: Antenna Diversity on the BTS A9100 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25Figure 4: Transmission Components in the BSS with A9120 BSC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26Figure 5: Cell Mapping . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29Figure 6: Logical Position of External Components Associated with BSS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33Figure 7: Location Update . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38Figure 8: TMN System Hierarchy . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40Figure 9: General Telecommunication Layers in GSM . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42Figure 10: BSS Application, Transmission Layers and Interfaces . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43Figure 11: Time Slot 4 of a TDMA Frame Supporting Access Grant Channels . . . . . . . . . . . . . . . . . . . . . . . . . 48Figure 12: Model LLC Packet Data Unit used in GPRS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 63Figure 13: The Alcatel GPRS Solution in the PLMN . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 64Figure 14: GPRS Attach . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 93Figure 15: Mobile Station-Originating Packet Data Protocol Context Activation . . . . . . . . . . . . . . . . . . . . . . . . 95Figure 16: GGSN-Originating Packet Data Protocol Context Activation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 96Figure 17: Mobile-Originated Data Transfer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 97Figure 18: Mobile-Terminated Data Transfer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 98Figure 19: Mobile-Originating Packet Data Protocol Context De-activation . . . . . . . . . . . . . . . . . . . . . . . . . . . 106Figure 20: Network-Originating Packet Data Protocol Context De-activation Processes . . . . . . . . . . . . . . . 107Figure 21: GPRS Suspend . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 109Figure 22: GPRS Resume . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 110Figure 23: Mobile Station-Originating GPRS Detach . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 112Figure 24: Network-Originating GPRS Detach Procedures . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 113Figure 25: Generic LCS Logical Architecture . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 115Figure 26: Radio and Link Establishment for Mobile-Originated Call . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 131Figure 27: SDCCH Channel Activation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 133Figure 28: Immediate Assignment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 134Figure 29: Connection for Mobile-Originated Call . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 137Figure 30: Normal Assignment for Mobile-Originated Call . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 141Figure 31: Channel Activation Process for the Traffic Channel . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 143Figure 32: Channel Assignment Process for the Traffic Channel . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 144Figure 33: Call Connection for Mobile-Originated Call . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 145Figure 34: Radio and Link Establishment for Mobile-Terminated Call . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 146Figure 35: Normal Assignment for Mobile-Terminated Call . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 148Figure 36: CCCH with Three Blocks Reserved for AGCH . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 150Figure 37: Four TDMA Frame Cycles Providing 24 Paging Sub-channels . . . . . . . . . . . . . . . . . . . . . . . . . . . . 151Figure 38: Paging Message Sequence . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 154Figure 39: Location Update with Classmark Update . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 163

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Figures

Figure 40: Location Update with Mobile Station Sending Location Area Identity of Previous VLR . . . . . . . 165Figure 41: Ciphering Process . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 170Figure 42: Example of TFO Establishment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 172Figure 43: Frequency Hopping within an FHS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 181Figure 44: Different Forms of Discontinuous Transmission . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 187Figure 45: Power Control Flow of Measurement and Decision Action . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 190Figure 46: Power Output Balancing Based on Received Quality and Signal Levels . . . . . . . . . . . . . . . . . . . . 191Figure 47: Quality and Level Handover . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 198Figure 48: Better Zone Handover . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 199Figure 49: Better Cell Handover (Power Budget) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 200Figure 50: Distance Handover . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 201Figure 51: Umbrella Cell Load in Mobile Velocity Dependent Handover . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 202Figure 52: Asynchronous External Handover . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 206Figure 53: Mobile Station Disconnecting a Call . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 217Figure 54: Normal Call Release . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 218Figure 55: Initiation of Normal Release by MSC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 219Figure 56: BSC/BTS/Mobile Station Interactions in Normal Call Release . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 221Figure 57: Normal Release Final Steps . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 222Figure 58: Call Release Following a Channel Change . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 223Figure 59: Call Release Following Reset . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 225Figure 60: BSC-initiated Call Release toward the MSC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 226Figure 61: BTS-initiated Call Release following LAPD Failure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 230Figure 62: Call Release due to Mobile Station-Initiated Radio Link Failure . . . . . . . . . . . . . . . . . . . . . . . . . . . 231Figure 63: Call Release due to Communication Failure detected by Transcoder . . . . . . . . . . . . . . . . . . . . . . 232Figure 64: Encoded Speech Transmission Across the BSS with A9120 BSC . . . . . . . . . . . . . . . . . . . . . . . . . 236Figure 65: Multiplexed Ater Interface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 238Figure 66: Data Transmission Across the BSS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 246Figure 67: Short Message Service - Cell Broadcast . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 249Figure 68: Example: Cell Configurations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 255Figure 69: Sectored Site Configuration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 257Figure 70: Example of Extended Cell Topology . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 258Figure 71: Umbrella Cell with Mini Cells . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 261Figure 72: Example: Handovers due to Threshold Triggering . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 264Figure 73: Indoor Cell Example Network Hierarchy with Three Layers and Two Bands . . . . . . . . . . . . . . . . 265Figure 74: Multiple HMI Access to OMC-Rs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 275Figure 75: ACO Links . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 276Figure 76: X.25 Without Redundancy . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 277Figure 77: X.25 With Redundancy . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 277Figure 78: RSL Correlation on the Abis Interface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 290Figure 79: Example: Alarm Report . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 292

3BK 21222 AAAA TQZZA Ed.01 9 / 306

Figures

Figure 80: Example: Loss of Carrier Unit Holding BCCH. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 298

10 / 306 3BK 21222 AAAA TQZZA Ed.01

Tables

TablesTable 1: Types of Call Set Up . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19Table 2: Network Subsystem Components . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34Table 3: Traffic Channels . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 49Table 4: Control Channels . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 50Table 5: System Information Messages . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 55Table 6: GPRS System Information Message . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 68Table 7: Gb Interface Functions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 69Table 8: BSCGP Interface Functions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 70Table 9: GPRS Mobility Management States . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 73Table 10: Cell Reselection Modes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 74Table 11: Network Operation Modes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 79Table 12: Time Slot Allocation Parameters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 81Table 13: Autonomous Packet Resource Allocation Time Slots . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 83Table 14: TBF Allocation Types . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 90Table 15: PDCH Traffic Load States . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 91Table 16: HSDS Terminology . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 120Table 17: Types of Calls . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 128Table 18: Call Set Up Phases . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 129Table 19: Cell List Identifier and Paging Performed . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 152Table 20: Paging Request Message and Mobile Station Identification . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 153Table 21: Classmark Handling . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 159Table 22: Classmark IE Field Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 161Table 23: Classmark Configuration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 162Table 24: Mobile Station Ciphering Capabilities . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 167Table 25: Downlink Discontinuous Transmission Status in Channel Activation . . . . . . . . . . . . . . . . . . . . . . . . 184Table 26: Operator Discontinuous Transmission Options . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 186Table 27: Radio Link Measurements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 189Table 28: Mobile Station Maximum and Minimum Power Ranges . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 192Table 29: Target Cell Handover Types . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 205Table 30: Handovers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 209Table 31: AMR Configuration Parameters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 243Table 32: Circuit-Switched Data Rate Conversions Across the Air Interface . . . . . . . . . . . . . . . . . . . . . . . . . . 247Table 33: Subsystem O&M Functions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 271Table 34: Configuration Management Functions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 279Table 35: Fault Management Functions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 286Table 36: BTS Alarm Hardware Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 293Table 37: BTS Alarms Functional Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 293Table 38: Performance Management Functions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 300Table 39: Audit Types . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 304

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Preface

PrefacePurpose This document provides detailed descriptions of the functions and features

of the Alcatel BSS. Some functions and features may not be available onthe system installed at your location.The technical information in this document covers:

Mobile Communications SupportThese areas describe how the BSS handles communications between amobile station and the NSS. It follows a call through the Alcatel BSS, anddescribes how each element in the system functions individually, and withother elements. This shows how the BSS and its units react as a system.

Operations and Maintenance (O&M).These areas describe the O&M functions within the system. It describesboth local and distributed O&M functions in a BSS.

Whats New In Edition 01Update sections after review Extended GSM (Section 1.4), GPRS Channels andSystem Information Messages (Section 2.2), Results Analysis (Section 8.6.4)Update section 2G to 3G Handover (Section 1.8.2) with regards for compressedmessages in call setup step.Update section 2G to 3G Reselection (Section 1.8.3) with TDSCDMA feature.Update section 2G to 3G Reselection (Section 1.8.3) with availability incase of NC2.Update section Cell Reselection Modes (Section 2.4.3.1) with NC2 relatedrestriction.Update section Modulation and Coding Schemes (Section 2.9.2.2) withrecommendation on IR activation.Update section Multi-GPU per BSS (Section 1.3.4.3) for 1 GSL configuredon GPU.

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The following improvements are added:

DTM in Dual Transfer Mode (Section 1.7.9.5)MCCCH in Control Channels (Section 1.7.9.4)MCS reduction on the flight & WRR in MAC Algorithm (Section 2.7.3.8)MX capacity improvements in HSL Links (Section 1.7.7)

Audience This manual is for people requiring an in-depth understanding of the functionsof the Alcatel BSS:

Network decision makers who require an understanding of the underlyingfunctions of the system, including:

Network plannersTechnical design staffTrainers.

Operations and support staff who need to know how the system operates innormal conditions, including:

OperatorsSupport engineersMaintenance staffClient Help Desk personnel.

Assumed Knowledge The document assumes that the reader has an understanding of:

GSMGPRS

Mobile Telecommunications

Network Management concepts and terminology.

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1 Introduction

1 Introduction

This section gives a brief overview of the Alcatel BSS, its functions and features.

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1 Introduction

1.1 OverviewThe BSS provides radio coverage for GSM subscribers in a defined area. Itsprincipal role is to provide and support signaling and traffic channels betweenmobile stations and the NSS.The following figure shows the BSS within the PLMN, and its links to the PSTNand the PSDN in a fixed network.

Base Station SubsystemMobile Stations

NetworkSubsystem

FixedNetwork

PLMN

OMCR

NMC

MFS

BTS

SGSN

MSC PSTN

TCBSC

PSDN

Router

AGPSserver

MFS : Multi-BSS Fast Packet ServerNMC : Network Management CenterPSDN : Packet Switched Data NetworkPSTN : Public Switched Telephone NetworkSGSN : Serving GPRS Support NodeFigure 1: BSS in the PLMN

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1 Introduction

1.1.1 Evolium Radio SolutionsTo respond to the swiftly evolving needs in the BSS, Alcatel offers the EvoliumRadio Solutions.The Alcatel Evolium Radio Solutions include the following BSS equipmentdescribed in this document:

A9120 BSC

A9130 BSC

G2 Transcoder

A9125 Transcoder

BTS A9100

BTS A9110

A9135 MFS

A9130 MFS.

Note: BTS G1 and BTS G2 are still supported by Evolium.

1.1.2 Extended GSM Band (E-GSM)The Alcatel BSS supports the E-GSM band. E-GSM consists of:

The 900 MHz primary band, called the P-GSM band. This uses 890-915MHz for uplink, and 935-960 MHz for downlink

The 900 MHz extended band, called the G1 band. This uses 880-890 MHzfor uplink, and 925-935 MHz for downlink.

This corresponds to a total number of 174 addressable frequencies.

1.1.3 GSM 850The GSM 850 MHz band was introduced in Release 1999 of the 3GPPStandard in 1999 to allow operators to progressively replace the D-AMPS andCDMA technologies that were using these frequencies. Besides certain Asiancountries, the GSM 850 MHz band concerns in particular the Latin Americancountries where many operators already use the GSM system in their networkwith GSM 1900 MHz to extend or replace their existing D-AMPS network. Theterm GSM 850 is used for any GSM system which operates in the 824 MHz to849 MHz band for the uplink direction and in the 869 MHz to 894 MHz band forthe downlink direction. The GSM 850 band is defined by 124 absolute radiofrequency channel numbers (ARFCN) among the 1024 ARFCNs available inthe GSM standard.

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1.1.4 Frequency Band ConfigurationsThe Alcatel BSS supports the following multiband network configurations:

BSS with a mix of GSM 850 and GSM 1900 cells

BSS with a mix of GSM 850 and GSM 1800 cells

BSS with a mix of GSM 900 and GSM 1800 cells

BSS with a mix of GSM 900 and GSM 1900 cells.

Refer also to the Basic GSM System Specifications .

1.1.5 GPRSGPRS, the solution chosen by European Telecommunication StandardsInstitute to answer the demand for increased data transmission rates, isavailable in the Alcatel BSS. This means there are now two parallel systemsin the PLMN: circuit-switched transmission for voice, and packet-switchedtransmission for data. For information on how GPRS functions in the BSS,see GPRS in the BSS (Section 2) .

1.2 BSS FunctionsFunctions are defined by the International Telecommunications Union andEuropean Telecommunication Standards Institute recommendations.This section provides an overview of the BSS functions with a system-wideview; that is, how the BSS functions work together within the system. Networkelements and functional units are indicated where applicable, but are notdescribed. For more information, refer to the specific network elementdescription manuals, such as the BTS Functional Description .The BSS provides signaling and traffic channels between the mobile stationand the NSS. To ensure a high level of service to the subscribers, the BSSoffers the following functions :

Call Set Up

Call Handling

Call Release

Operations & Maintenance.

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1.2.1 Call Set UpCall Set Up is used for speech and data calls. The three basic types of call areshown in the following table.

Type of Call Description

Mobility Management Mobility Management calls, such as location update,are used by the system to gather mobile stationinformation. The exchanges are protocol messagesonly. Therefore, only a signaling channel is used.

SupplementaryService

Supplementary service calls, such as SMS, allowthe mobile station to send and receive messages toand from the BTS. These calls pass small amountsof information. Therefore, only a signaling channelis used.

User Traffic User traffic calls, such as speech or data callsto a correspondent, can pass large amountsof information. Therefore, they require greaterbandwidth than a signaling channel. These callsuse traffic channels.

Table 1: Types of Call Set Up

Call set up processes include:

Radio and Link Establishment to assign a signaling channel betweenthe mobile station and the NSS

Classmark handling to manage different mobile station power and cipheringcapabilities

Ciphering to ensure data security on the Air Interface

The normal assignment process to assign a traffic channel between themobile station and the NSS.

See Call Set Up (Section 3) for more information.

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1.2.2 Call HandlingThe call handling function is used to supervise and maintain calls which arein progress. Call handling involves:

In-call channel modification during a call

Maintenance of call integrity and quality through features such as FrequencyHopping, Discontinuous Transmission or Radio Power Control

Handover to change channels when a mobile station moves from onecell to another

Handover when the quality of the current channel drops below an acceptablelevel

Ciphering to ensure data security on the Air Interface

Overload control to manage the call load on the system.

See Call Handling (Section 4) for more information.

1.2.3 Call ReleaseThe call release function ensures that resources allocated to a call are free forreuse when they are no longer required by the current call.Specifically the Call Release function includes:

Call Release in normal service:Calls terminated by call managementCalls terminated following a channel change.

Special cases:Call release following a resetBSC-initiated releaseBTS-initiated releaseMobile station-initiated release.

See Call Release (Section 5) for more information.

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1 Introduction

1.2.4 Operations & MaintenanceO&M provides the operator interface for the management and control of theBSS, and its interconnection to the NSS. O&M is divided into three principalareas:

Configuration Management

Fault Management

Performance Management.

See Operations & Maintenance (Section 8) for more information.

1.3 BSS ComponentsThere are three main units in the BSS:

The BSC, which acts as the controller of the BSS. The BSC providescontrol of the BTS and their resources, and performs switching functionswithin the BSS

The BTS, which provides the radio transmission and reception functionsfor a cell

The Transcoder, which performs rate adaptation and encoding/decoding ofspeech and data between the MSC and the BSC.

The BSS shown in Figure 1 is supervised by the OMC-R. In a large network,one or more high-level supervisors, such as NMCs, can exist to centralizenetwork management activities. The NMC has the authority to send directivesto the OMC-R.For more information about the NMC, refer to documentation supplied withthe NMC.

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1.3.1 Base Station ControllerThe BSC provides control of the BTS and manages radio resources and radioparameters. From a transmission point of view, the BSC also performs aconcentration function if more radio traffic channels than terrestrial channels areconnected to the MSC. A single BSC can control a large number of BTS. Theexact number is a function of the BSC equipment and the configurations used.The BSC provides:

Resource management

Database management

Radio measurement processing

Channel management

Operations and maintenance functions within the BSS

Communication with the OMC-R

Switching between the Air Interface channels (and their associated Abischannels), and the A Interface channels. Further information concerningthese interfaces can be found in The A Interface (Section 1.7.4) , The AbisInterface (Section 1.7.6) and The Air Interface (Section 1.7.9) .

The A9120 BSC also incorporates the following transmission equipment:

The Base Station Interface Equipment (BSIE), which performs signaling andsubmultiplexing on the Abis Interface

The Transcoder Submultiplexer Controller (TSC), which collects andprocesses transmission data. It also provides an operator interface tocertain transmission functions via a Local Maintenance Terminal.

For a more detailed description of the A9120 BSC, refer to the Evolium BSC/TCOverall Description document.In the A9130 BSC the transmission equipments are replaced by virtualtransmission processes, like the other A9120 BSC old functions. For amore detailed description of the A9130 BSC, refer to A9130 BSC EvolutionFunctional Description

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1 Introduction

1.3.2 Base Transceiver StationThe BTS provides radio transmission, control and baseband functions for acell. The BTS also supports the Air Interface with the mobile stations. Alcatelprovides two families of BTS:

BTS G1 or G2

BTS A9100 or BTS A9110.

These families of BTS have different architectures, and are not functionallyidentical, (e.g., only the BTS A9100 or BTS A9110 can support GPRS).The BTS performs the following functions under the control of the BSC:

Transmit and receive functions

Antenna diversity

Frequency hopping

Radio channel measurements

Radio frequency testing.

The BTS also includes BIEs which enable it to communicate with the BSC overthe Abis Interface. In the BTS A9100 and BTS A9110, the BIE is integratedinto the SUM.For a more detailed description of the BTS, refer to the BTS FunctionalDescription or the Evolium BTS A9100/A9110 Functional Descriptiondocuments.For BTS name you can use any combination of the following characters: a-z,A-Z, 0 - 9, -, _ (hyphen, underscore). Blank spaces are permitted in the BTSname. Use the rules from O&M Parameters Dictionary

1.3.2.1 Antenna DiversityAntenna Diversity is a BTS feature that protects against multipath fading. Thisis achieved by duplicating the receive antenna and receive path up to the FrameUnit of the BTS (or the TRE for a BTS A9100 or BTS A9110). The Frame Unit(or TRE) uses the data burst which has the fewest errors. This increases thelow-power mobile station range, thereby allowing larger cells.

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1.3.2.2 G1 and G2 BTS Antenna DiversityAntenna diversity on G1 and G2 BTS duplicates the receive antenna andreceive path up to the Frame Unit. The Frame Unit uses the data burst whichhas the fewest errors. This increases low-power mobile station range, thusallowing larger cells and lowering infrastructure investment.The following figure shows the antenna diversity path through the G1 andG2 BTS.

BASEBANDCONTROLCONTROL

BASEBAND RADIO COUPLING

OMU

BIE

FHU

OTHER ANTENNAE

TX

CUFU

aaa

b b b

ab best of a&b

COUPLING UNIT

aRX

RX

(option)b

BIE : Base Station Interface EquipmentCU : Carrier UnitFHU : Frequency Hopping UnitFU : Frame UnitOMU : Operations and Maintenance UnitRX : ReceiverTX : Transmitter

Figure 2: Antenna Diversity on G1 and G2 BTS

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1 Introduction

1.3.2.3 BTS A9100/A9110 Antenna DiversityAntenna diversity on the BTS A9100 or BTS A9110 follows the same principleas in the G1 and G2 BTS. The antennae are used for both transmit and receive,and the receive path is duplicated up to the TRE, providing the same gain inefficiency and low-power mobile station range.The following figure shows the antenna diversity path through the BTS A9100.

TRE 1

TRE 2

TRE 3

TRE 4

BASEBAND

CONTROL

RADIO

SUM

ANy ANx

RADIOCOMBINING DUPLEXING

ANT a

ANT b

ab

Tx / Rx

Tx / Rx

b

b

b

a

a

a

best of a&b

best of a&b

best of a&b

best of a&b

b

a

ba

b

a

b

a

ab

ab

ab

ab

BASEBAND

ANC

ANT : AntennaANx : Antenna Network Type xANy : Antenna Network Type ySUM : Station Unit ModuleTRE : Transmitter/Receiver EquipmentFigure 3: Antenna Diversity on the BTS A9100

Note: The configuration shown above (1 Sector, 3X4 Transceivers) is one exampleonly. Other combinations of Antennae and TREs are possible. There is no ANyin the BTS A9110, and ANy is not needed if the sector has two TREs.

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1.3.3 Transcoder And Transmission FunctionThe Transcoder is the key component for the transmission function, whichprovides efficient use of the terrestrial links between the equipment of the BSS.In addition to the Transcoder, Submultiplexers are also used for transmissionfunctions.The Transcoder provides:

Conversion between A-law and Radio Test Equipment-Long Term Predictionencoded traffic (speech)Conversion between A-law and Algebraic Code Excited Linear Predictionencoded traffic (speech)Rate adaptation (data)O&M control of the transmission function.

The Transcoder is normally located next to the MSC.The Submultiplexer performs submultiplexing on the Ater Interface, betweenthe MSC and the BSC. When submultiplexing is used, a Submultiplexer islocated at each end of the link.The following figure shows how transmission components are distributed inthe BSS with A9120 BSC.

BTS BSC

MSC

BSC

TC

TCBTS

BTSTSC

BIE

BIE

BIE SM SM

TSC

BIE

OMCR

BIE : Base Station Interface EquipmentSM : SubmultiplexerTSC : Transcoder Submultiplexer ControllerTC : TranscoderFigure 4: Transmission Components in the BSS with A9120 BSC

Similarly with A9120, BSS with the A9130 BSC differs by that the transmissioncomponents are replaced by virtual transmission processors.

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1 Introduction

1.3.4 The Multi-BSS Fast Packet ServerThe MFS is preferably located at the Transcoder/MSC site.It is internal to the BSS and provides the following functions:

PCU (Packet Control Unit) functions:PAD (packet assembly/disassembly) functionScheduling of packet data channelsAutomatic Retransmission Request functionsChannel access control functionsRadio channel management functions.

The Gb Interface protocol stack.

The MFS converts GPRS frames, carried on multiple 16 kb/s links from multipleBTS, to one or more frame relay channels connected to the SGSN on the GbInterface. See The Gb Interface (Section 2.3.1) for details.The set up of Packet Data Channels is controlled by the MFS. It also negotiatesresources with the BSC and routes GPRS packets. When an additional channelis required on a BTS, the MFS asks the BSC to allocate a channel and toconnect it to an Ater channel which the MFS controls.The Alcatel solution also supplies two dedicated GPRS interfaces between theMFS and the BSS:

The BSCGP Interface supplies routing of GPRS messages and resourcenegotiation between the BSC and the MFS

The GCH Interface routes user data traffic and signaling between the MFSand the BTS transparently (to the BSC).

Hardware and software management of the MFS is provided using the IMT.

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1.3.4.1 GPRS Processing UnitsThe MFS is divided into GPRS processing units (GPU) which areinterconnected via an Ethernet bus and controlled by a control station. TheGPU handles the O&M and telecom functions of several cells, but a cell cannotbe shared between several GPUs.A GPU cannot be connected to more than one BSC, which means that eachGPU cannot manage simultaneously several BSSs. Even so, the use ofseveral GPUs per BSS is required for traffic capacity reasons. The MFS isin charge of associating each cell with a GPU. This later operation is calledGPU cell mapping.The GPU is in charge of:

O&M functions:Initialization of the MFSSoftware downloadSoftware configurationPerformance monitoring.

Telecom functions:Radio and transmission resources controlRadio link control of packet connectionsCommon control channels managementMS radio resource controlLogical Link Control (LLC)Protocol Data Unit (PDU) transferMultiframe managementCongestion controlGb Interface managementSignaling management on the GSL Interface.

1.3.4.2 GPU Protocol ManagementThe GPU is split into two sub-units, the Packet Management Unit (PMU)and the Packet Traffic Unit (PTU).The protocols handled by a GPU are split in the following manner:

Protocols handled by the PTU:Radio Interface protocols (RLC and MAC)GCH Interface protocols (L2-GCH and L1-GCH).

The PTU manages the corresponding GCH Interface (see The GCHInterface (Section 2.3.3) for more information).Protocols handled by the PMU:

Gb Interface protocols (BSSGP, Network Service, and Full Rate)BSC Interface protocols (BSCGP, L2-GSL, and L1-GSL)RRM protocol.

The PMU manages the corresponding Gb and GSL interfaces.

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1.3.4.3 Multi-GPU per BSSTo increase the GPRS capacity of the BSS in terms of number of PDCH,several GPU boards can be connected to the BSC to support the PCU function.This feature is applied regardless of the BTS type.For one BSC, in case of multi GP configuration, if the last GSL of any GPUis lost, all GPUs assigned to the BSS will be reseted (reset_data) and PSoutage occurs.The only exceptions are the following:

GSL loss on GPU which have all cells locked

GSL loss on GPU and the other GPU have also their GSL down.

1.3.4.4 Cell MappingMapping a cell means that a cell is associated with a GPU. Remapping acell means that a cell, already linked to a GPU, is moved to another GPU.The mapping of cells onto GPUs is performed by the MFS, which actuallydefines the mapping of cells onto LXPUs (logical GPU). An LXPU is eitherthe primary GPU, or the spare GPU in the case of switchover. All the GPRStraffic of one cell is handled by only one GPU. The following figure shows anexample of cell mapping.

MFS

GPU1

GPU2

GPU3

GPU4

BSC

Cell 1Cell 2Cell 4

Cell 3

Cell 8Cell 9Cell 12

Cell 11

Cell 5Cell 6

Cell 7

Cell 14Cell 13

Cell 10

GPU : GPRS Processing UnitFigure 5: Cell Mapping

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1.4 Extended GSMTwo 10 MHz extended bands for GSM 900 in the range 880-890 MHz/925-935MHz have been specified as an option on a national basis. The reason forthis is mainly due to the lack of primary band frequencies in countries outsideEurope. The term "G1" is used for the extended band. The term "P-GSM" isused for the primary band. The term "E-GSM" is used for the whole GSM 900frequency band, i.e., the primary band (890-915 MHz/935-960 MHz) plusthe extended band (880-890 MHz/925-935 MHz). This corresponds to 174addressable carrier frequencies and leads to an increase of 40% against the124 frequencies in the primary band.With the Enhanced E-GSM Band Handling feature, which is supported byEvolium BTS only, (E)GPRS and all types of signaling channels are carried onthe frequencies in the entire E-GSM band (e.g., primary and extended), whenthe parameter EGSM_RR_ALLOC_STRATEGY is set to 1 (same behavior for E-GSMcapable mobile stations). When the parameter EGSM_RR_ALLOC_STRATEGY isset to the default value of 0 (different behavior for E-GSM capable mobilestations), the OMC-R does not allow the operator to define the BCCH, CCCH,SDCCH and CBCH on an E-GSM TRX.Both P-GSM only and E-GSM mobile stations are supported in thenetwork, but are handled differently, depending on the value to whichthe EGSM_RR_ALLOC_STRATEGY parameter is set. When the parameterEGSM_RR_ALLOC_STRATEGY is set to the default value of 0 , the BSS handlesE-GSM capable mobiles stations differently from P-GSM only mobile stations.When the parameter EGSM_RR_ALLOC_STRATEGY is set to 1 , the BSS handlesP-GSM only and E-GSM capable mobile stations in E-GSM cells in the sameway, that is, the BSS assumes that all GSM 900 mobiles are E-GSM capable.E-GSM TRXs are preferred to support (E)GPRS in E-GSM cells, and only whenthe parameter EGSM_RR_ALLOC_STRATEGY is set to 0 . An E-GSM cell is one inwhich FREQUENCY_RANGE = EGSM or EGSM-DCS1800 .An E-GSM TRX is a TRX configured with:

Frequencies in the G1 band only, or

Frequencies in both the P-GSM and G1 bands.

For information on radio resource allocation with Enhanced E-GSM BandHandling, refer to TCH Allocation for E-GSM and P-GSM Mobile Stations(Section 1.4.4) .

1.4.1 E-GSM Mobile Station RecognitionFrom messages sent by the mobile station, the BSS determines if a mobilesupports the E-GSM band.The mobile station is determined to be E-GSM if:

The FC bit of Classmark 2 is set to 1 (regardless of the value of the Band2 bit of Classmark 3) orThe FC bit of Classmark 2 is set to 0, and the Band 2 bit of Classmark3 is set to 1.

If the information is not available, the mobile station is considered as notsupporting the G1 band. The BSS never triggers a Classmark Interrogationprocedure to obtain the E-GSM ability of a mobile station.

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1.4.2 E-GSM Management After Initial DeterminationOnce the E-GSM ability has been initially determined as described above, themobile station radio characteristics might change during a transaction. If theBSC receives a classmark change message, it takes this into account andupdates the E-GSM ability according to the content of the received message.

1.4.3 E-GSM Determination at HandoverIn the case of internal handover, the E-GSM ability of a mobile station isstored in the BSC memory. In the case of external incoming Handover, thehandover request message includes either Classmark 1 or Classmark 2 IE,and optionally Classmark 3 IE. If Classmark 1 is present and Classmark 3 isnot present or Classmark 3 is present but does not contain the Band 2 bit,the mobile station is not considered as E-GSM. If both Classmark 1 andClassmark 3 are present, and Classmark 3 contains the Band 2 bit, the BSCgets the E-GSM ability of the mobile station from Classmark 3. If Classmark2 is present and Classmark 3 is not present, or Classmark 3 is present butdoes not contain the Band 2 bit, the BSC gets the E-GSM ability of the mobilestation from Classmark 2 ("FC" bit).If both Classmark 2 and Classmark 3 are present, the mobile station is seenas E-GSM:

If the FC bit of Classmark 2 is set to 1 (whatever the value of the band 2bit of Classmark 3)If the FC bit of Classmark 2 is set to 0 and the band 2 bit of Classmark3 is set to 1.

After an incoming external handover, if a classmark change message hasbeen received from the mobile station, the BSC ignores any subsequentclassmark update message received from the MSC.

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1.4.4 TCH Allocation for E-GSM and P-GSM Mobile StationsThe allocation of G1 band channels can be done for Normal Assignment(NASS), Internal Channel Change (ICC), or External Channel Change (ECC).Each TRE has the capability to support the P-GSM or the E-GSM band. EachTRX is configured as a P-GSM TRX or an E-GSM TRX. Since with enhancedE-GSM band handling P-GSM and G1 frequencies can be mixed in the FHS,when a TCH is needed, the BSC first checks the frequencies in the FHS. If atleast one frequency belongs to the G1 band, the related TRX is considered asan E-GSM TRX. TCHs are then allocated as described below.In an E-GSM cell, when the parameter EGSM_RR_ALLOC_STRATEGY is set to 0 ,when allocating a TCH to serve circuit-switched requests, the BSC selects theTCH in the following order:

For E-GSM capable mobile stationsFirst, a radio time slot which IS E-GSM capable but NOT PS capableNext, a radio time slot which is NEITHER E-GSM capable NOR PScapableThirdly, a radio time slot which is NOT E-GSM capable but IS PS capableLastly, a radio time slot which is E-GSM capable and PS capable.

For P-GSM capable only mobile stationsFirst, a radio time slot which is NEITHER E-GSM capable NOR PScapableNext, a radio time slot which is NOT E-GSM capable but IS PS capable.

When the parameter EGSM_RR_ALLOC_STRATEGY is set to 1 , the BSS assumesthat all GSM 900 mobile stations are E-GSM capable, and handles P-GSM onlyand E-GSM capable mobile stations in E-GSM cells in the same way.In multiband concentric cells, the above allocation only applies to the outer zone.When the parameter EGSM_RR_ALLOC_STRATEGY is set to 0 , in an E-GSMcell, when allocating a PDCH to serve packet-switched requests and basedon the TRX ranking provided to the MFS, the BSC selects the TCH in theorder given below:

First, a radio time slot which is E-GSM capable AND PS capable

Next, a radio time slot which is NOT E-GSM capable but IS PS capable.

When the parameter EGSM_RR_ALLOC_STRATEGY is set to 1 , the BSS handlesP-GSM only and E-GSM capable mobile stations in E-GSM cells in the sameway.

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1.5 External ComponentsThe BSS communicates with three external components:

The NSS on the A Interface

The mobile station on the Air Interface

The OMC-R on the BSS/OMC-R Interface.

The following figure shows the logical position of the External Components.

Base Station SubsystemMobile

Stations Network

SubsystemFixed

Network

PLMN

OMCR

NMC

MFS

MSCTranscoder

PSDN

HLR

AbisInterface

Ater Interface

Gb Interface

AInterfaceBTS

BTS

BTS

BSC

PSTN

GGSNSGSN

Router

AGPSserver

GGSN : Gateway GPRS Support NodeHLR : Home Location RegisterMFS : Multi-BSS Fast Packet ServerNMC : Network Management CenterPSDN : Packet Switched Data NetworkPSTN : Public Switched Telephone NetworkSGSN : Serving GPRS Support NodeFigure 6: Logical Position of External Components Associated with BSS

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1.5.1 Network SubsystemManaging communication within the PLMN and external networks is the primaryrole of the NSS. The NSS manages the subscriber administration databases.It contains these components:

Component Description

MSC Performs and coordinates the outgoing and incomingCall Set Up function. The MSC is a large capacity switchused for passing mobile traffic to mobile subscribers, or tosubscribers of external networks. This part of the NSSinterfaces with the BSS.

Home LocationRegister

The HLR is the central database within a given network formobile subscriber specific data. It contains static data suchas access authorization, information about subscribers andsupplementary services. It also controls the dynamic dataabout the cell in which the mobile station is located.

VisitorLocationRegister

The VLR temporarily stores information about mobilestations entering its coverage area. Linked to one or moreMSCs, the VLR transmits data to a new VLR when a mobilestation changes areas.

AuthenticationCenter

The AuC manages the security data used for subscriberauthentication.

EquipmentIdentityRegister

The EIR contains the lists of mobile station equipmentidentities.

Table 2: Network Subsystem Components

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1.5.2 Mobile StationsMobile stations provide radio and processing functions which allow subscribersto access the mobile network via the Air Interface. Subscriber-relatedinformation is stored on a specific device called a SIM.The SIM is a removable smart-card that conforms to internationally recognizedstandards. It contains the IMSI. This is used by the Network Operator toidentify the subscriber in the network and to provide security and protectionagainst misuse.Each mobile station has its own IMEI. The IMEI is used by the NetworkOperator to prevent stolen or non-type approved mobile stations from accessingthe network.There are three types of mobile station in GSM:

Phase 1

Phase 1 extended

Phase 2.

For information on GPRS mobile stations, refer to GPRS Elements (Section2.1.2) .Mobile stations have different capabilities according to the class of mobilestation and the purpose for which the mobile station was designed. Thesedifferences include power output and ciphering.Only phase 2 mobile stations can turn off ciphering, or change the cipheringmode, during a channel change procedure such as a handover. The cipheringcapability of a mobile station is signalled to the BSS in the mobile stationclassmark.Ciphering is used to protect information transmitted on the Air Interface. Thisis performed between the BTS and the mobile station (i.e., Air Interface).Transmission ciphering does not depend on the type of data to be transmitted(i.e., speech, user data, signaling), but on normal transmission bursts. SeeCiphering (Section 3.8) for further information concerning mobile stationciphering capabilities.

1.5.2.1 Mobile Station Idle ModeA mobile station is in idle mode when it is switched on, but not communicatingwith the network on an SDCCH or a traffic channel.The BSS supports four idle mode functions:

Cell selection and cell reselection

GSM/GPRS to UMTS cell reselection

Location updating

Overload control.

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1.5.2.2 Mobile Station Cell Selection and ReselectionA mobile station monitors the broadcast messages from the BTS. This includesmonitoring the FCCH and SCH.The mobile station chooses the best cell on which to camp. If this cell is in alocation area other than that stored in the mobile station memory, then themobile station initiates a location update procedure. For a mobile station tocamp on a cell, it has to synchronize with the cell.The BTS broadcasts an FCCH and an SCH at a defined time in the BCCHcycle. These channels are used as reference points for the mobile station tosynchronize with the BCCH. Once synchronized, the mobile station continuesto monitor these channels to stay synchronized.This type of synchronization, along with cell configuration and channelfrequency information, enables the mobile station to calculate where channelsoccur in the multiframe sequences.Timing advance information is sent to the mobile station when an SDCCH isassigned. The mobile station uses the channel configuration informationto calculate which part of the CCCH contains its paging message, andtherefore which time slot to monitor for paging messages. When the mobilestation is camped on a cell, it continues to monitor the BCCH transmissionsfrom neighboring cells. The BCCH frequencies of the neighboring cellsare transmitted on the BCCH of the home cell (sys_info 2 ). The mobilest