Radiolocation in Ubiquitous Wireless Communication (eBook)

Preface 6
Acknowledgments 9
Contents 10
1 Physical Principles of Radio Communication 13
1.1 Introduction 13
1.2 Electromagnetic Wave in Empty Space 14
1.3 The Plane Wave 16
1.4 Electromagnetic Wave Within Matter 19
1.4.1 Dielectrics 21
1.4.2 Conductors 23
1.5 Basics of Antennas 25
1.5.1 Antenna Arrays 27
1.5.2 Reflector Antennas 31
1.5.3 Patch Antennas 33
2 Radiolocation with Multiple Directional Antennas 35
2.1 Introduction 35
2.2 Rotated Lobe Theorem 37
2.3 Reconstruction of the Wave's Direction 39
2.3.1 Variational Error 40
2.3.2 Numerical Significance of the Lobe's Shape 44
2.3.2.1 Rotational Variation 44
2.3.2.2 Scaling Variation 46
2.3.3 The Optimization Algorithm 47
2.3.4 Aliasing, or Too Few Antennas 49
2.3.5 Sources Above and Below the Antenna Plane 55
2.3.6 A design Example 58
2.4 Implementation of a Compound Antenna 59
3 Forming the Radio Image with Multiple Antennas 61
3.1 Introduction 61
3.1.1 Note on Coherent Sources 62
3.2 Representing the Antenna Signal in a Set of Basis Functions 62
3.3 Image Formation in Circular Geometry 66
3.3.1 Image Resolution 69
3.3.2 Aliasing Again 72
3.3.3 Radio Image on the Circle 75
3.3.4 Peak Interactions 78
3.4 Image Formation in Spherical Geometry 79
3.4.1 Radio Image on the Sphere 83
4 Radiolocator Design: High-Frequency Front End 86
4.1 Design Requirements and General Architecture 86
4.1.1 Radiolocation and the Receiver's Signal Path 89
4.2 Front End of the Serial Architecture 91
4.2.1 Directional Antenna Elements 91
4.2.2 Design of the Radio-Frequency Multiplexer 92
4.2.2.1 Trace Impedance and Reflections 95
4.2.2.2 Path Attenuation 96
4.2.2.3 Crosstalk 97
4.2.2.4 Wave Propagation in RF Traces 98
4.3 Radiolocator's Tuner 100
5 Radiolocator Design: Power Measurement and Digital Data Path 103
5.1 Design Requirements 103
5.2 Power Meter at the Heart of Radiolocation 104
5.3 Digitization of the Power Measurements 108
5.4 Data Collection Cycle 109
6 Application to Wireless Networking: Tracking Sources in Real Time 113
6.1 Introduction 113
6.2 Radiolocation Baseband 115
6.3 Integration of Two Data Paths 116
6.3.1 Internal Label 117
6.3.2 External Label 119
6.4 The Communication Data Path 119
6.5 The Timestamp 122
6.6 Test of the Radiolocator Access Point 123
7 Application to Wireless Networking: Adaptive Response 127
7.1 Introduction 127
7.2 Circular Phased Array 127
7.2.1 Phase Shifting 129
7.2.2 Simultaneous Use of Multiple Antennas 130
7.3 Design Requirements of the Adaptive Response 132
7.4 Overview of the Adaptive-Response Architecture 134
7.5 Test of the Adaptive Directional Response 138
8 Engineering Aspects of the Transceiver Design 139
8.1 Introduction 139
8.2 Radiolocator Board 140
8.2.1 Subsystems 140
8.2.1.1 Controller FPGA 143
8.2.1.2 USB Communication Interface 143
8.2.1.3 Radiolocation Tuner 143
8.2.1.4 Measurement Unit 144
8.3 CalRadio Transceiver 146
8.3.1 DSP Hardware 146
8.3.2 DSP Data Path 147
8.3.3 The ARM Processor and Data Path 150
8.3.4 Baseband and RF Sections 152
8.4 The Laboratory Prototype 152
9 Wider Application of Radiolocation in Digital Wireless Communication 155
9.1 Introduction 155
9.2 Frequency Hopping 802.11 155
9.3 Bluetooth 156
9.4 802.11g 157
9.5 Orthogonal Frequency-Division Multiplexing 157
9.6 802.11a 159
9.7 Code-Division Multiple Access 160
9.8 Summary 162
10 Appendices 165
10.1 The Laplacian Operator 165
10.2 Antenna Reciprocity 166
10.2.1 Lorentz Reciprocity Theorem 166
10.2.2 Reciprocal Two-Port Device 167
10.2.3 Two-Antenna Measurement System 169
10.3 Fundamentals of Radio Communication 171
10.4 Transmission Lines 175
10.4.1 Free Space in One Dimension 175
10.4.2 Impedance Discontinuities 178
10.5 Power Flux in the Modulated Signal 179
10.6 Overview of the 802.11b Standard 181
10.6.1 Types of Networks 181
10.6.2 Physical Layer 182
10.6.3 Medium Access Control Layer 184
10.7 Wilkinson Divider 186
10.8 Spherical Harmonics 188
Index 191