Practical Guide to MIMO Radio Channel

List of Abbreviations xiii

List of Symbols xvii

1 Introduction 1

1.1 From SISO to MISO/ SIMO to MIMO 2

1.1.1 Single Input Single Output SISO 2

1.1.2 Single Input Multiple Output, SIMO, and Multiple Input Single Output, MISO 3

1.1.3 Multiple Input Multiple Output, MIMO 6

1.2 What Do We Need MIMO For? 7

1.2.1 The Single User Perspective 8

1.2.2 The Multiple User Perspective 8

1.3 How Does MIMO Work? Two Analogies 10

1.3.1 The Single User Perspective 10

1.3.2 The Multiple User Perspective 12

1.4 Conditions for MIMO to Work 13

1.5 How Long Has MIMO Been Around? 14

1.6 Where is MIMO Being Used? 15

1.7 Purpose of the Book 16

2 Capacity of MIMO Channels 17

2.1 Some Background on Digital Communication Systems 18

2.1.1 Generation of Digital Signals 18

2.1.2 Conversion/Formatting for Transmission 19

2.1.3 Complex Baseband Representation 19

2.1.4 Decoder 19

2.2 Notion of Capacity 20

2.2.1 Abstract Communication System 20

2.2.2 Definition of Capacity 22

2.2.3 Capacity Achieving Transceivers 23

2.3 Channel State Information and Fading 24

2.3.1 Fast and Slow Fading 24

2.3.2 Channel State Information 26

2.4 Narrowband MIMO Model 27

2.5 Capacity of the Time-Invariant Channel 28

2.5.1 Capacity of the Time-Invariant SISO Channel 29

2.5.2 Time-Invariant SIMO Channel 30

2.5.3 Time-Invariant MISO Channel 32

2.5.4 Time-Invariant MIMO Channel: A Set of Parallel Independent AWGN Channels 34

2.5.5 Maximal Achievable Rate for Fixed Input Covariance Matrix 43

2.6 Fast Fading Channels with CSIT Distribution: Ergodic Capacity 46

2.6.1 Ergodic Capacity: Basic Principles 47

2.6.2 Fast Fading SISO Channel with CSIT Distribution 47

2.6.3 Fast Fading SIMO Channel with CSIT Distribution 48

2.6.4 Fast Fading MISO Channel with CSIT Distribution 49

2.6.5 Fast Fading MIMO Channels with CSIT Distribution 49

2.7 Slow Fading Channel with CSIT Distribution: Outage Probability and Capacity with Outage 54

2.7.1 Outage: Basic Principles 55

2.7.2 Diversity to Improve Communication Reliability 57

2.7.3 Slow Fading SISO Channels with CSIT Distribution 58

2.7.4 Slow Fading SIMO Channel with CSIT Distribution: Receive Diversity 60

2.7.5 Slow Fading MISO Channel with CSIT Distribution: Transmit Diversity 60

2.7.6 Slow Fading MIMO Channel with CSIT Distribution 62

2.8 Chapter Summary Tables 67

2.9 Further Reading 73

3 MIMO Transceivers 75

3.1 MIMO Receivers 76

3.1.1 General MIMO Architecture 76

3.1.2 Maximum Likelihood Receiver 78

3.1.3 Classes of Receivers Considered in the Chapter 78

3.1.4 Spatial Matched Filtering 80

3.1.5 Zero Forcing Receiver 86

3.1.6 MMSE Receiver 92

3.1.7 SIC Receiver and V-Blast 97

3.1.8 Performance 103

3.2 Transceivers with CSI at Transmitter and Receiver: Transmit and Receive Beamforming 108

3.2.1 Principle of Beamforming 108

3.2.2 Multiple Transmit and Receive Beams 109

3.2.3 Transmit Beamforming (MISO System) 111

3.2.4 Receive Beamforming (SIMO) 112

3.2.5 Single Beam MIMO: Maximal Eigenmode Beamforming 113

3.2.6 Eigenmode Transmission 114

3.2.7 Performance of Beamforming Schemes 118

3.3 Space-Time Block Codes 122

3.3.1 Orthogonal Design for a 2 × 1 MISO System: Alamouti STBC 123

3.3.2 STBC for More than Two Transmit Antennas 128

3.4 D-Blast 133

3.4.1 Diagonal Encoding 133

3.4.2 Diagonal Decoding 134

3.4.3 D-Blast: Outage Optimal 135

3.4.4 Performance Gains 135

3.4.5 Error Propagation 136

3.4.6 Numerical Evaluations: Comparison of D-Blast with STBC 136

3.5 Chapter Summary Tables 138

3.6 Further Reading 143

4 MIMO Channel Models 145

4.1 SISO Models and Channel Fundamentals 146

4.1.1 Models for the Prediction of the Power 146

4.1.2 Models for the Prediction of the Temporal Variation of the Channel 152

4.1.3 Narrowband and Wideband Channels 160

4.1.4 Polarisation 166

4.1.5 Summary of Parameters Required for SISO Channel Modelling 167

4.2 Challenges in MIMO Channel Modelling 167

4.2.1 Deterministic Models 169

4.2.2 Stochastic Models 171

4.3 Summary 190

5 MIMO Antenna Design 193

5.1 Antenna Element Fundamentals 194

5.1.1 Isotropic Radiator 194

5.1.2 Directivity and Gain 195

5.1.3 Far Field and Rayleigh Distance 196

5.1.4 Three Dimensional Antenna Patterns 197

5.1.5 Impedance and Return Loss 198

5.1.6 Reciprocity 199

5.1.7 Antenna Polarisation 199

5.1.8 Mean Effective Gain 202

5.2 Single Antenna Design 205

5.3 Designing Array Antennas for MIMO 207

5.3.1 Spatial Correlation 207

5.3.2 Angular and Polarised Correlation 209

5.3.3 Impact of Nonuniform Angles of Arrival 211

5.4 Impact of Antenna Design on the MIMO Radio Channel 212

5.5 Evaluating Antenna Impact on the MIMO Channel 217

5.5.1 A Crude Evaluation of the Impact of Antennas on MIMO Channel Capacity 217

5.5.2 Advanced Techniques to Evaluate MIMO Antenna Performance 219

5.6 Challenges in Compact MIMO Antenna Design and Examples 221

5.7 Summary 223

5.7.1 Antenna Fundamentals 223

5.7.2 Designing Antenna Arrays 223

5.7.3 Practical Antennas for MIMO 223

6 MIMO in Current and Future Standards 225

6.1 Wireless Channel Modelling in Standards 225

6.2 Current Wireless Standards Employing MIMO and the Corresponding Channel Models 228

6.2.1 IEEE 802.11n 228

6.2.2 IEEE 802.16-WiMAX 231

6.2.3 3GPP-LTE 235

6.2.4 Comparison of the IEEE 802.11n, WiMAX and 3GPP Models 238

6.3 MIMO in Other Areas 240

6.3.1 MIMO for DVB-T2 240

6.3.2 MIMO in the HF Band 241

6.3.3 MIMO for Satellite Communications 242

6.3.4 Ultrawideband MIMO 242

6.3.5 MIMO for On-body Communications 243

6.3.6 MIMO for Vehicular Communications 244

6.3.7 MIMO in Small Cellular Environments 244

6.4 Concluding Remarks and Future Wireless Systems 245

Appendix: Some Useful Definitions 247

Bibliography 251

Index 257