FUNDAMENTALS OF WIMAX: UNDERSTANDING BROADBAND WIRELESS NETWORKING

WiMAX is the most promising new technology for broadband wireless access to IP services. It can serve an extraordinary range of applications and environments: data, voice, and multimedia; fixed and mobile; licensed and unlicensed. However, until now, wireless professionals have had little reliable information to guide them. Fundamentals of WiMAX is the first comprehensive guide to WiMAX—its technical foundations, features, and performance. Three leading wireless experts systematically cut through the hype surrounding WiMAX and illuminate the realities. They combine complete information for wireless professionals and basic, accessible knowledge for non-experts. Professionals will especially appreciate their detailed discussion of the performance of WiMAX based on comprehensive link- and system-level simulations.

Foreword xix
Preface xxi
Acknowledgments xxiii
About the Authors xxvii

Part I Overview of WiMAX 1
Chapter 1 Introduction to Broadband Wireless 3
1.1 Evolution of Broadband Wireless 5
1.2 Fixed Broadband Wireless: Market Drivers and Applications 10
1.3 Mobile Broadband Wireless: Market Drivers and Applications 12
1.4 WiMAX and Other Broadband Wireless Technologies 13
1.5 Spectrum Options for Broadband Wireless 17
1.6 Business Challenges for Broadband Wireless and WiMAX 21
1.7 Technical Challenges for Broadband Wireless 23
1.8 Summary and Conclusions 32
1.9 Bibliography 32

Chapter 2 Overview of WiMAX 33
2.1 Background on IEEE 802.16 and WiMAX 33
2.2 Salient Features of WiMAX 37
2.3 WiMAX Physical Layer 39
2.4 MAC-Layer Overview 47
2.5 Advanced Features for Performance Enhancements 55
2.6 Reference Network Architecture 57
2.7 Performance Characterization 59
2.8 Summary and Conclusions 61
2.9 Bibliography 63

Part II Technical Foundations of WiMAX 65
Chapter 3 The Challenge of Broadband Wireless Channels 67
3.1 Communication System Building Blocks 68
3.2 The Broadband Wireless Channel: Pathloss and Shadowing 69
3.3 Cellular Systems 77
3.4 The Broadband Wireless Channel: Fading 84
3.5 Modeling Broadband Fading Channels 91
3.6 Mitigation of Fading 104
3.7 Summary and Conclusions 110
3.8 Bibliography 110

Chapter 4 Orthogonal Frequency Division Multiplexing 113
4.1 Multicarrier Modulation 114
4.2 OFDM Basics 117
4.3 An Example: OFDM in WiMAX 123
4.4 Timing and Frequency Synchronization 124
4.5 The Peak-to-Average Ratio 131
4.6 OFDM's Computational Complexity Advantage 142
4.7 Simulating OFDM Systems 144
4.8 Summary and Conclusions 145
4.9 Bibliography 145

Chapter 5 Multiple-Antenna Techniques 149
5.1 The Benefits of Spatial Diversity 150
5.2 Receive Diversity 154
5.3 Transmit Diversity 157
5.4 Beamforming 169
5.5 Spatial Multiplexing 174
5.6 Shortcomings of Classical MIMO Theory 181
5.7 Channel Estimation for MIMO-OFDM 184
5.8 Channel Feedback 189
5.9 Advanced Techniques for MIMO 190

Chapter 6 Orthogonal Frequency Division Multiple Access 199
6.1 Multiple-Access Strategies for OFDM 200
6.2 Multiuser Diversity and Adaptive Modulation 204
6.3 Resource-Allocation Techniques for OFDMA 209
6.4 OFDMA in WiMAX: Protocols and Challenges 216
6.5 Summary and Conclusions 219
6.6 Bibliography 220

Chapter 7 Networking and Services Aspects of Broadband Wireless 223
7.1 Quality of Service 224
7.2 Multimedia Session Management 233
7.3 Security 241
7.4 Mobility Management 249
7.5 IP for Wireless: Issues and Potential Solutions 260
7.6 Summary and Conclusions 265
7.7 Bibliography 266

Part III Understanding WiMAX and Its Performance 269
Chapter 8 PHY Layer of WiMAX 271
8.1 Channel Coding 272
8.2 Hybrid-ARQ 278
8.3 Interleaving 279
8.4 Symbol Mapping 280
8.5 OFDM Symbol Structure 280
8.6 Subchannel and Subcarrier Permutations 282
8.7 Slot and Frame Structure 290
8.8 Transmit Diversity and MIMO 292
8.9 Closed-Loop MIMO 296
8.10 Ranging 300
8.11 Power Control 302
8.12 Channel-Quality Measurements 303
8.13 Summary and Conclusions 304
8.14 Bibliography 304

Chapter 9 MAC Layer of WiMAX 307
9.1 Convergence Sublayer 309
9.2 MAC PDU Construction and Transmission 312
9.3 Bandwidth Request and Allocation 316
9.4 Quality of Service 317
9.5 Network Entry and Initialization 319
9.6 Power-Saving Operations 324
9.7 Mobility Management 327
9.8 Summary and Conclusions 332
9.9 Bibliography 333

Chapter 10 WiMAX Network Architecture 335
10.1 General Design Principles of the Architecture 336
10.2 Network Reference Model 337
10.3 Protocol Layering Across a WiMAX Network 341
10.4 Network Discovery and Selection 344
10.5 IP Address Assignment 344
10.6 Authentication and Security Architecture 345
10.7 Quality-of-Service Architecture 349
10.8 Mobility Management 352
10.9 Radio Resource Management 359
10.10 Paging and Idle-Mode Operation 360
10.11 Summary and Conclusions 362
10.12 Bibliography 362

Chapter 11 Link-Level Performance of WiMAX 365
11.1 Methodology for Link-Level Simulation 366
11.2 AWGN Channel Performance of WiMAX 370
11.3 Fading Channel Performance of WiMAX 373
11.4 Benefits of Multiple-Antenna Techniques in WiMAX 387
11.5 Advanced Receiver Structures and Their Benefits for WiMAX 396
11.6 Summary and Conclusions 398
11.7 Bibliography 399

Chapter 12 System-Level Performance of WiMAX 401
12.1 Wireless Channel Modeling 402
12.2 Methodology for System-Level Simulation 404
12.3 System-Level Simulation Results 412
12.4 Summary and Conclusions 421
12.5 Appendix: Propagation Models 422
12.6 Bibliography 427

Acronyms
Index