Preface ix
Acknowledgements xi
List of Abbreviations xiii
1 Introduction 1
1.1 The Early History of Antennas 1
1.2 Antennas and Electromagnetic Radiation 2
1.2.1 Electromagnetic Radiation 2
1.2.2 Short Wire Dipole Radiation 5
1.3 The Modern History of Antennas 6
1.4 Frequency Spectrum and Antenna Types 8
1.4.1 Dipole Antennas 8
1.4.2 Loop Antennas 9
1.4.3 Aperture Antennas 10
1.4.4 Reflector Antennas 10
1.4.5 Array Antennas 11
1.4.6 Modern Antennas 11
1.5 Organization of the Book 12
1.6 Problems 13
References 13
2 Antenna System-Level Performance Parameters 15
2.1 Radiation Pattern 15
2.1.1 Field Regions 16
2.1.2 Three-Dimensional Radiation Pattern 17
2.1.3 Planar Cuts 19
2.1.4 Power Patterns 22
2.1.5 Directivity and Gain 25
2.1.6 Antenna Beamwidth 28
2.2 Antenna Impedance and Bandwidth 29
2.3 Polarization 32
2.3.1 Elliptical Polarization 33
2.3.2 Circular Polarization 35
2.3.3 Linear Polarization 35
2.3.4 Axial Ratio 36
2.4 Antenna Effective Area and Vector Effective Length 38
2.4.1 Effective Area 38
2.4.2 Vector Effective Length 40
2.5 Radio Equation 41
2.6 Radar Equation 43
2.6.1 Radar Cross-Section 44
2.7 Problems 46
References 47
3 Vector Analysis 49
3.1 Addition and Subtraction 49
3.2 Products 50
3.2.1 Scalar Product or Dot Product 50
3.2.2 Vector Product or Cross Product 51
3.2.3 Triple Product 52
3.3 Differentiation 53
3.3.1 Gradient 54
3.3.2 Divergence 55
3.3.3 Curl 57
3.4 Problems 61
4 Radiated Fields 63
4.1 Maxwell Equations 63
4.2 Vector Potential 64
4.3 Far-Field Approximations 69
4.3.1 Magnetic Field 69
4.3.2 Electric Field 73
4.4 Reciprocity 75
4.4.1 Lorentz Reciprocity Theorem 75
4.4.2 Antenna Reciprocity 77
4.5 Problems 79
References 79
5 Dipole Antennas 81
5.1 Elementary Dipole 81
5.1.1 Radiation 82
5.1.2 Input Impedance 86
5.2 Non-Infinitesimal Dipole Antenna 87
5.2.1 Radiation 87
5.2.2 Input Impedance 96
5.3 Printed Monopole and Inverted-F Antennas 97
5.3.1 Application of Theory 98
5.3.2 Planar Monopole Antenna Design 99
5.3.3 Printed UWB Antenna Design 105
5.3.4 Miniature Monopole with Cable Current Suppression
113
5.3.5 Inverted-F Antenna Design 120
5.4 Problems 128
References 129
6 Loop Antennas 131
6.1 General Constant Current Loop 131
6.1.1 Radiation 132
6.1.2 Input Impedance 136
6.1.3 Small Loop Antenna 137
6.1.4 Comparison of Short Dipole and Small Loop Antenna
138
6.2 Printed Loop Antenna 139
6.2.1 Application of Theory 139
6.2.2 Design of a Printed Loop Antenna 143
6.3 Problems 149
References 152
7 Aperture Antennas 153
7.1 Magnetic Sources 154
7.2 Uniqueness Theorem 156
7.3 Equivalence Principle 158
7.4 Radiated Fields 160
7.5 Uniform Distribution in a Rectangular Aperture 161
7.6 Uniform Distribution in a Circular Aperture 166
7.7 Microstrip Antennas 170
7.7.1 Application of Theory 172
7.7.2 Design of a Linearly Polarized Microstrip Antenna
175
7.7.3 Design of a Circularly Polarized Microstrip Antenna
179
7.8 Problems 185
References 188
8 Array Antennas 189
8.1 A Linear Array of Non-Isotropic Point-Source Radiators
189
8.2 Array Factor 195
8.3 Side Lobes and Grating Lobes 195
8.3.1 Side-Lobe Level 196
8.3.2 Grating Lobes 196
8.4 Linear Phase Taper 197
8.5 Grating Lobes 202
8.6 Special Topics 203
8.6.1 Mutual Coupling 203
8.6.2 Antenna Diversity 212
8.6.3 Sequential Rotation and Phasing 213
8.7 Array Antenna Design 217
8.7.1 Theory 220
8.7.2 A Linear Microstrip Patch Array Antenna 221
8.8 Problems 229
References 230
Appendix A Effective Aperture and Directivity 231
Appendix B Vector Formulas 235
Appendix C Complex Analysis 237
C.1 Complex Numbers 237
C.2 Use of Complex Variables 240
Appendix D Physical Constants and Material Parameters
243
References 244
Appendix E Two-Port Network Parameters 245
Appendix F Transmission Line Theory 249
F.1 Distributed Parameters 249
F.2 Guided Waves 252
F.2.1 VSWR and Reflection Factor 254
F.2.2 Impedance and Relative Impedance 254
F.3 Input Impedance of a Transmission Line 255
F.4 Terminated Lossless Transmission Line 255
F.4.1 Matched Load 255
F.4.2 Short Circuit 256
F.4.3 Open Circuit 256
F.4.4 Imaginary Unit Termination 257
F.4.5 Real Termination 257
F.5 Quarter Wavelength Impedance Transformer 257
Appendix G Coplanar Waveguide (CPW) 259
References 260
Index 261
