Description
Book SynopsisThis book focuses on the key functional areas of LTE Self-Organizing Networks (SON), first introducing LTE network scenarios, technologies, and general SON concepts, and on to the latest status of 3GPP standardization.
Table of ContentsForeword xiii
Preface xv
List of Contributors xix
Acknowledgements xxi
List of Abbreviations xxiii
1. Introduction 1
1.1 Self-Organising Networks (SON) 3
1.2 The Transition from Conventional Network Operation to SON 6
1.2.1 Automation of the Network Rollout 9
1.2.2 Automation of Network Optimisation and Troubleshooting 10
1.2.3 SON Characteristics and Challenges 11
References 12
2. LTE Overview 13
2.1 Introduction to LTE and SAE 13
2.1.1 3GPP Structure, Timeline and LTE Specifications 14
2.1.2 LTE Requirements 16
2.1.3 System Architecture Overview 16
2.1.4 Evolved UTRAN 18
2.1.5 E-UTRAN Functional Elements 19
2.1.6 Evolved Packet Core 21
2.1.7 Voice over LTE (VoLTE) 24
2.1.8 LTE-Advanced 24
2.1.9 Network Management 30
2.2 LTE Radio Access Network Scenarios and Their Evolution 33
2.2.1 LTE Radio Coverage Scenario 33
2.2.2 LTE for Capacity Enhancement in Existing GERAN/UTRAN 34
2.2.3 Enhancing LTE Capacity, the Multi-Layer LTE 34
2.2.4 Data Offloading, LIPA-SIPTO 35
2.2.5 Multi-Radio Access Network Scenarios or non-GPP 36
References 37
3. Self-Organising Networks (SON) 39
3.1 Vision 39
3.2 NGMN Operator Use Cases and 3GPP SON Use Cases 42
3.2.1 Operational Use Cases 42
3.2.2 NGMN SON Use Cases and Requirements 47
3.2.3 SON Use Cases in 3GPP 50
3.3 Foundations for SON 52
3.3.1 Control Engineering: Feedback Loops 53
3.3.2 Autonomic Computing and Autonomic Management 55
3.3.3 SON Research Projects 57
3.4 Architecture 60
3.4.1 Use-Case Related Criteria 62
3.4.2 System-Level Criteria 64
3.5 Business Value 65
3.5.1 The Economics of eNB Sites 65
3.5.2 General Mode of Operation of SON 68
3.5.3 Installation and Planning 71
3.5.4 Network Optimisation 72
3.5.5 Fault Management 73
3.5.6 Conclusions 74
3.6 SON Operational and Technical Challenges 75
3.6.1 Transition of Operational Processes to SON 75
3.6.2 Technical (Engineering) Challenges 78
References 80
4. Self-Configuration (‘Plug-and-Play’) 81
4.1 Auto-Connectivity and -Commissioning 82
4.1.1 Preparation 85
4.1.2 Connectivity Setup, Site-Identification and Auto-Commissioning 87
4.1.3 LTE-A Relay Auto-Connectivity 93
4.1.4 Conclusions 100
4.2 Dynamic Radio Configuration 100
4.2.1 Generation of Initial Transmission Parameters 106
4.2.2 Physical Cell-ID Allocation 111
4.2.3 Automatic Neighbour Relationship Setup (ANR) 118
4.2.4 DRC Architecture 130
4.2.5 Conclusions 132
References 133
5. Self-Optimisation 135
5.1 Mobility Robustness Optimisation 136
5.1.1 Goals of MRO 136
5.1.2 Cell Changes and Interference Challenges 137
5.1.3 MRO Relevant Parameters 140
5.1.4 Causes for Mobility Problems 144
5.1.5 MRO Solutions 146
5.1.6 MRO Time Scales 151
5.1.7 MRO Performance 152
5.2 Mobility Load Balancing and Traffic Steering 157
5.2.1 Introduction to Traffic Steering 157
5.2.2 SON Policies for Mobility Load Balancing 159
5.2.3 A Theoretical View of Load Balancing 160
5.2.4 Standardised Features and Procedures to Direct UEs to the Desired Layer 166
5.2.5 Exemplary Results of MLB 182
5.2.6 Uplink Load Balancing 189
5.2.7 Interactions Between TS/MLB and MRO 190
5.3 Energy Saving 193
5.3.1 Introduction 193
5.3.2 Requirements 195
5.3.3 Energy Saving Management 195
5.3.4 eNB Overlaid Scenario 196
5.3.5 Capacity-Limited Network 198
5.3.6 Equipment/Local ES 200
5.3.7 Example Scenarios and Expected Gains 201
5.3.8 Summary 204
5.4 Coverage and Capacity Optimisation 204
5.4.1 CCO with Adaptive Antennas 205
5.4.2 Performance Analysis for Antenna Parameter Optimisation Based CCO 208
5.4.3 CCO with TX Power 216
5.5 RACH Optimisation 217
5.5.1 General 217
5.5.2 PRACH Configuration 218
5.5.3 RACH Configuration 219
5.5.4 RACH/PRACH Configuration Example 221
5.5.5 RA Performance 222
5.5.6 Self-Optimisation Framework 223
5.5.7 UE Reporting 223
5.5.8 Inter-eNB Communication 225
5.6 RRM and SON (Interference Coordination, P0 Optimisation) 226
5.6.1 Interference Coordination 226
5.6.2 P0 Optimisation 230
References 232
6. Self-Healing 235
6.1 Introduction 236
6.1.1 3GPP Use Cases 236
6.1.2 3GPP Self-Healing Process and its Management 237
6.1.3 Cell Degradation Management 238
6.2 Cell Degradation Detection 242
6.3 Cell Degradation Diagnosis and Prediction 248
6.3.1 Rule Based Systems 250
6.3.2 Bayesian Networks 251
6.3.3 Case Based Reasoning 253
6.3.4 Neural Networks 255
6.3.5 Active Measurements 256
6.3.6 Prediction 257
6.4 Cell Outage Compensation 259
6.4.1 Activation of Cell Outage Compensation 260
6.4.2 Means of Cell Outage Compensation 260
6.4.3 Interaction between Cell Outage Compensation and Self-Configuration Functions 263
References 264
7. Supporting Function: Minimisation of Drive Tests (MDT) 267
7.1 Introduction 267
7.1.1 General 267
7.1.2 History and Background 269
7.2 Relation to SON 272
7.3 Requirements 273
7.4 Use Cases 275
7.4.1 Operator Scenarios 276
7.4.2 Coverage Optimisation 277
7.4.3 Mobility Optimisation 281
7.4.4 Capacity Optimisation 281
7.4.5 Parameterisation for Common Channels 282
7.4.6 QoS Verification 282
7.5 Overall Architecture 283
7.6 Managing MDT 285
7.6.1 Subscriber and Equipment Trace 285
7.6.2 MDT Configuration Parameters 285
7.6.3 Subscription Based MDT 287
7.6.4 Area Based MDT 292
7.6.5 Supporting Functionality in the Management System 293
7.6.6 MDT Reporting 293
7.7 MDT Radio Interface Procedures 295
7.7.1 Immediate MDT 296
7.7.2 Logged MDT 298
7.7.3 RLF Reporting 303
7.7.4 Measurement Parameters 305
7.7.5 Location Information 308
7.8 Conclusion 309
References 310
8. SON for Core Networks 311
8.1 Introduction 311
8.2 SON for Packet Core Networks 311
8.2.1 Packet Core Element Auto-Configuration 311
8.2.2 Automatic Neighbour Relation 313
8.2.3 S1 Flex (MME Pooling) 314
8.2.4 Signalling Optimisation 315
8.2.5 Latency Optimisation 317
8.2.6 Fast Gateway Convergence with Bidirectional Forward Detection 318
8.2.7 Dynamic IP Pool Allocation 318
8.2.8 Energy Saving 319
8.3 SON for Voice Core Networks 319
8.3.1 Voice Over IP Quality Monitoring and Management 319
8.3.2 Resource Optimisation in Voice Core Network 320
References 321
9. SON Operation 322
9.1 SON Function Interactions 323
9.1.1 Spatial Characteristic 324
9.1.2 Temporal Characteristic 324
9.1.3 Categories of SON Conflicts 326
9.1.4 Network Parameters Related to SON Functions 329
9.1.5 Examples for Conflicts between SON Functions 330
9.2 Coordination of SON Functions 334
9.2.1 Basic Options for SON Coordination 334
9.2.2 Goals of SON Function Coordination 338
9.2.3 SON Coordination Function Concept 340
9.2.4 Coordination Schemes 346
9.2.5 Related Work 352
9.2.6 SON Function Coordination Example 352
9.3 Conclusions 355
References 356
10. SON for Heterogeneous Networks (HetNet) 357
10.1 Introduction 357
10.2 Standardisation and Network Architecture 359
10.2.1 Network Architecture for HetNet 361
10.3 Self-Configuration 362
10.3.1 Auto-Connectivity and -Commissioning 363
10.3.2 Automatic Site Identification and Hardware-to-Site Mapping 364
10.3.3 Automatic Neighbour Relations (ANR) 365
10.4 Self-Optimisation: Interference Management 365
10.4.1 Interference Characteristics in HetNet Scenarios 365
10.4.2 Basic Interference Management Techniques 366
10.4.3 Scenarios with Macro eNBs and Micro/Pico eNBs 369
10.4.4 Enhanced Time-Domain Interference Management: eICIC 370
10.4.5 Outlook on Further Interference Management Innovations 374
10.5 Self-Optimisation: Mobility Aspects; MRO and Traffic Steering 375
10.5.1 Mobility Robustness Optimisation 375
10.5.2 Multi-Layer Traffic Steering and Load Balancing 377
10.5.3 IEEE 802.11 (WiFi) Integration 378
References 378
11. Future Research Topics 379
11.1 Future Mobile Network Scenarios 379
11.1.1 Heterogeneous Networks 379
11.1.2 Cloud RAN 380
11.1.3 Requirements for Future OAM Systems 381
11.2 Cognitive Radio Networks (CRN) 381
11.2.1 From SON to CRN 381
11.2.2 Definitions 382
11.2.3 Framework 383
11.2.4 Artificial Intelligence 385
11.3 Applications 387
11.3.1 Self-Configuration 387
11.3.2 Self-Optimisation 387
11.3.3 Self-Healing 388
11.3.4 Operation 388
11.4 Conclusion 389
References 389
Index 391
