OFDM for Wireless Communications Systems -- Contents.pdf -- Preface xiii -- Acknowledgments xv -- 1 Introduction 1 -- 1.1 Wireless Technology in the Future 1 -- 1.1.1 WWANs 3 -- 1.1.2 WLANs 4 -- 1.1.3 WPANs 5 -- 1.1.4 WB-PANs 6 -- 1.1.5 The Next Generation 7 -- 1.2 Orthogonal Frequency-Division Multiplexing 11 -- 1.2.1 History of OFDM 11 -- 1.3 Concluding Remarks 14 -- References 16 -- 2 WLANs 19 -- 2.1 Introduction 19 -- 2.1.1 WLANs in a Nutshell 21 -- 2.1.2 IEEE 802.11, HIPERLAN/2, and MMAC WLAN Standards 23 -- 2.2 MAC in WLAN Standards 27 -- 2.2.1 IEEE 802.11 27 -- 2.2.2 HIPERLAN/2 31 -- 2.3 QoS over WLANs 33 -- 2.3.1 IEEE 802.11e 33 -- 2.3.2 Interframe Spacing 35 -- 2.3.3 Other QoS-Related Developments 36 -- 2.4 Security in IEEE 802.11 36 -- 2.4.1 Current IEEE 802.11 36 -- 2.4.2 IEEE 802.11i and IEEE 802.11f 39 -- References 43 -- Appendix 2A: ISM Bands 46 -- Appendix 2B: Comparison of WLAN and WPAN Standards 47 -- 3 WPANs 49 -- 3.1 Introduction 49 -- 3.1.1 Emergence of Personal Area Networking (The Person-Centered Concept) 49 -- 3.2 Technical Challenges of a WPAN Technology 54 -- 3.2.1 Ad Hoc Connectivity 55 -- 3.2.2 Service Discovery and Resource Selection 56 -- 3.3 Enabling Technologies 57 -- 3.3.1 Comparison of Short-Range Wireless Technologies 60 -- 3.4 Ongoing Research 60 -- 3.4.1 Architecture and Middleware Issues 60 -- 3.5 Research Issues for Future WPAN Technology 73 -- References 76 -- 4 Appropriate Channel Model for OFDM Systems 83 -- 4.1 Introduction 83 -- 4.2 Characterization of the Mobile Radio Channel 84 -- 4.2.1 Components of a Multipath Channel Model 84 -- 4.2.2 Definitions 85 -- 4.2.3 Variation of Channel Parameters Due to Bandwidth Limitation 90 -- 4.3 FD Channel Modeling 90 -- 4.3.1 The WSSUS Channel Model 91 -- 4.3.2 Channel Description 94 -- 4.3.3 Relation to (Physical) Channel Parameters 95.

4.4 FD Channel Simulation 97 -- 4.4.1 Model Description 98 -- 4.4.2 Implementation of the Simulation Scheme 99 -- 4.4.3 FD Simulation Results 100 -- 4.4.4 Differences from Time-Domain Simulation Schemes 104 -- 4.5 Application to Millimeter-Wave Radio Channels 104 -- 4.5.1 Discussion of Measurement Results 105 -- 4.5.2 Discussion of Channel Parameters 106 -- 4.5.3 Overview of Channel Models 110 -- 4.5.4 Applicability of the FD Model 111 -- 4.6 Conclusions 112 -- References 114 -- 5 Basics of OFDM and Synchronization 117 -- 5.1 Introduction 117 -- 5.2 OFDM Introduction and System Model 117 -- 5.2.1 OFDM Introduction and Block Diagram 118 -- 5.2.2 Design of the OFDM Signal 120 -- 5.2.3 OFDM System Model 123 -- 5.2.4 Synchronization Errors 128 -- 5.3 Performance of an Uncoded OFDM System 133 -- 5.3.1 Mathematical Modeling 133 -- 5.3.2 Analytical Evaluation of the BER 134 -- 5.3.3 Performance Results 141 -- 5.4 Conclusions and Recommendations 144 -- References 146 -- 6 The Peak Power Problem 149 -- 6.1 Introduction 149 -- 6.2 Distribution of the PAP Ratio 150 -- 6.3 Clipping and Peak Windowing 152 -- 6.3.1 Required Backoff with a Nonideal Power Amplifier 155 -- 6.3.2 Coding and Scrambling 158 -- 6.4 Peak Cancellation 160 -- 6.5 PAP Reduction Codes 166 -- 6.5.1 Generating Complementary Codes 167 -- 6.5.2 Minimum Distance of Complementary Codes 171 -- 6.5.3 Maximum-Likelihood Decoding of Complementary Codes 172 -- 6.5.4 Suboptimal Decoding of Complementary Codes 174 -- 6.5.5 Large Code Lengths 177 -- 6.6 Symbol Scrambling 177 -- References 180 -- 7 A Novel Hybrid OFDM Concept 183 -- 7.1 Introduction 183 -- 7.2 Detailed Structure of Various Multiple-Access Schemes 184 -- 7.2.1 Overview of Various Modulation Schemes 184 -- 7.2.2 DS-CDMA 187 -- 7.2.3 SFH Interface 188 -- 7.2.4 OFDM/CDMA/SFH System Description 191 -- 7.2.5 Summary 197.

7.3 Comparison to MC-CDMA 197 -- 7.3.1 Background 198 -- 7.3.2 Basic Principles of MC-CDMA 198 -- 7.3.3 The Hybrid System 201 -- 7.3.4 Comments on the MC-CDMA Technique 202 -- 7.3.5 Summary 205 -- 7.4 Analytical Performance in Fading Channels and Simulation in AWGN Channels 206 -- 7.4.1 Comparison of DS-CDMA and DS-CDMA-SFH (DS-SFH) Systems 206 -- 7.4.2 Noncoherent Class of Signals (DS-CDMA) 206 -- 7.4.3 DS-CDMA-SFH 208 -- 7.4.4 Coherent Class of Signals 211 -- 7.4.5 OFDM-CDMA-SFH (Hybrid) 211 -- 7.4.6 Simulations 213 -- 7.4.7 Summary 214 -- 7.5 Performance in Fading Channels with Perfect Estimation 215 -- 7.5.1 FD Modeling 215 -- 7.5.2 Analytical Evaluation of the BER 216 -- 7.5.3 Coherent Detection with Perfect Channel Estimation 218 -- 7.5.4 Calculation of the Parameters 219 -- 7.5.5 Simulations with Perfect Channel Estimation 220 -- 7.5.6 Summary 229 -- 7.6 Performance in Fading Channels with Realistic Estimation 229 -- 7.6.1 Baseband Model 230 -- 7.6.2 Channel Estimation with TDP Method 231 -- 7.6.3 Simulated OFDM System Parameters 235 -- 7.6.4 Simulation Results for QPSK/16-QAM 235 -- 7.6.5 Summary 237 -- 7.7 Conclusions 239 -- References 239 -- 8 A Practical OFDM System: Fixed Broadband Wireless Access (FBWA) 243 -- 8.1 Introduction 243 -- 8.2 Motivation 243 -- 8.2.1 Cell-Based Infrastructure 244 -- 8.2.2 Mesh TopologyŒBased Infrastructure 245 -- 8.3 Proposed FBWA 245 -- 8.4 Systems Requirements 248 -- 8.4.1 Parameter Selection 249 -- 8.4.2 Communications Protocol 249 -- 8.4.3 Duplex Schemes 250 -- 8.4.4 Downlink Transmission 250 -- 8.4.5 Uplink Transmission 252 -- 8.4.6 Frame Structure 253 -- 8.4.7 MAC Consideration and Conformance 254 -- 8.4.8 Adaptability of the Proposed Kernel Architecture to BWAS 256 -- 8.4.9 Summary 256 -- 8.5 Ubiquitous Connectivity 256 -- References 258 -- About the Author 263 -- Index 263 -- Library.