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Preface xiii About the Companion Website xix 1 Antennas 1
1.1 Introduction 1
1.2 Types of Antennas 3
1.3 Radiation Mechanism 7
1.4 Current Distribution on a Thin Wire Antenna 15
1.5 Historical Advancement 18
1.6 Multimedia 21 References 22 2 Fundamental Parameters and Figures-of-Merit of Antennas 25
2.1 Introduction 25
2.2 Radiation Pattern 25
2.3 Radiation Power Density 35
2.4 Radiation Intensity 37
2.5 Beamwidth 40
2.6 Directivity 41
2.7 Numerical Techniques 55
2.8 Antenna Efficiency 60
2.9 Gain, Realized Gain 61
2.10 Beam Efficiency 65
2.11 Bandwidth 65
2.12 Polarization 66
2.13 Input Impedance 75
2.14 Antenna Radiation Efficiency 79
2.15 Antenna Vector Effective Length and Equivalent Areas 81
2.16 Maximum Directivity and Maximum Effective Area 86
2.17 Friis Transmission Equation and Radar Range Equation 88
2.18 Antenna Temperature 96
2.19 Multimedia 100 References 103 Problems 105 3 Radiation Integrals and Auxiliary Potential Functions 127
3.1 Introduction 127
3.2 The Vector Potential A for an Electric Current Source J 128
3.3 The Vector Potential F for A magnetic Current Source m 130
3.4 Electric and Magnetic Fields for Electric (J) and Magnetic (M) Current Sources 131
3.5 Solution of the Inhomogeneous Vector Potential Wave Equation 132
3.6 Far-Field Radiation 136
3.7 Duality Theorem 137
3.8 Reciprocity and Reaction Theorems 138 References 143 Problems 143 4 Linear Wire Antennas 145
4.1 Introduction 145
4.2 Infinitesimal Dipole 145
4.3 Small Dipole 155
4.4 Region Separation 158
4.5 Finite Length Dipole 164
4.6 Half-Wavelength Dipole 176
4.7 Linear Elements Near or On Infinite Perfect Electric Conductors (PEC), Perfect Magnetic Conductors (PMC) and Electromagnetic Band-Gap (EBG) Surfaces 179
4.8 Ground Effects 203
4.9 Computer Codes 216
4.10 Multimedia 216 References 218 Problems 220 5 Loop Antennas 235
5.1 Introduction 235
5.2 Small Circular Loop 236
5.3 Circular Loop of Constant Current 250
5.4 Circular Loop with Nonuniform Current 259
5.5 Ground and Earth Curvature Effects for Circular Loops 268
5.6 Polygonal Loop Antennas 269
5.7 Ferrite Loop 270
5.8 Mobile Communication Systems Applications 272
5.9 Multimedia 272 References 275 Problems 277 6 Arrays: Linear, Planar, and Circular 285
6.1 Introduction 285
6.2 Two-Element Array 286
6.3 N-Element Linear Array: Uniform Amplitude and Spacing 293
6.4 N-Element Linear Array: Directivity 312
6.5 Design Procedure 318
6.6 N-Element Linear Array: Three-Dimensional Characteristics 319
6.7 Rectangular-to-Polar Graphical Solution 322
6.8 N-Element Linear Array: Uniform Spacing, Nonuniform Amplitude 323
6.9 Superdirectivity 345
6.10 Planar Array 348
6.11 Design Considerations 360
6.12 Circular Array 363
6.13 Multimedia 367 References 367 Problems 368 7 Antenna Synthesis and Continuous Sources 385
7.1 Introduction 385
7.2 Continuous Sources 386
7.3 Schelkunoff Polynomial Method 387
7.4 Fourier Transform Method 392
7.5 Woodward-Lawson Method 398
7.6 Taylor Line-Source (Tschebyscheff-Error) 404
7.7 Taylor Line-Source (One-Parameter) 408
7.8 Triangular, Cosine, and Cosine-Squared Amplitude Distributions 415
7.9 Line-Source Phase Distributions 416
7.10 Continuous Aperture Sources 417
7.11 Multimedia 420 References 420 Problems 421 8 Integral Equations, Moment Method, and Self and Mutual Impedances 431
8.1 Introduction 431
8.2 Integral Equation Method 432
8.3 Finite Diameter Wires 439
8.4 Moment Method Solution 448
8.5 Self-Impedance 455
8.6 Mutual Impedance Between Linear Elements 463
8.7 Mutual Coupling in Arrays 474
8.8 Multimedia 480 References 480 Problems 482 9 Broadband Dipoles and Matching Techniques 485
9.1 Introduction 485
9.2 Biconical Antenna 487
9.3 Triangular Sheet, Flexible and Conformal Bow-Tie, and Wire Simulation 492
9.4 Vivaldi Antenna 496
9.5 Cylindrical Dipole 500
9.6 Folded Dipole 505
9.7 Discone and Conical Skirt Monopole 512
9.8 Matching Techniques 513
9.9 Multimedia 523 References 524 Problems 525 10 Traveling Wave and Broadband Antennas 533
10.1 Introduction 533
10.2 Traveling Wave Antennas 533
10.3 Broadband Antennas 549
10.4 Multimedia 580 References 580 Problems 582 11 Frequency Independent Antennas, Antenna Miniaturization, and Fractal Antennas 591
11.1 Introduction 591
11.2 Theory 592
11.3 Equiangular Spiral Antennas 593
11.4 Log-Periodic Antennas 598
11.5 Fundamental Limits of Electrically Small Antennas 614
11.6 Antenna Miniaturization 619
11.7 Fractal Antennas 627
11.8 Multimedia 633 References 633 Problems 635 12 Aperture Antennas 639
12.1 Introduction 639
12.2 Field Equivalence Principle: Huygens'' Principle 639
12.3 Radiation Equations 645
12.4 Directivity 648
12.5 Rectangular Apertures 648
12.6 Circular Apertures 667
12.7 Design Considerations 675
12.8 Babinet''s Principle 680
12.9 Fourier Transforms in Aperture Antenna Theory 684
12.10 Ground Plane Edge Effects: The Geometrical Theory of Diffraction 702
12.11 Multimedia 707 References 707 Problems 709 13 Horn Antennas 719
13.1 Introduction 719
13.2 E-Plane Sectoral Horn 719
13.3 H-Plane Sectoral Horn 733
13.4 Pyramidal Horn 743
13.5 Conical Horn 756
13.6 Corrugated Horn 761
13.7 Aperture-Matched Horns 766
13.8 Multimode Horns 769
13.9 Dielectric-Loaded Horns 771
13.10 Phase Center 773
13.11 Multimedia 774 References 775 Problems 778 14 Microstrip and Mobile Communications Antennas 783
14.1 Introduction 783
14.2 Rectangular Patch 788
14.3 Circular Patch 815
14.4 Quality Factor, Bandwidth, and Efficiency 823
14.5 Input Impedance 826
14.6 Coupling 827
14.7 Circular Polarization 830
14.8 Arrays and Feed Networks 832
14.9 Antennas for Mobile Communications 837
14.10 Dielectric Resonator Antennas 847
14.11 Multimedia 858 References 862 Problems 867 15 Reflector Antennas 875
15.1 Introduction 875
15.2 Plane Reflector 875
15.3 Corner Reflector 876
15.4 Parabolic Reflector 884
15.5 Spherical Reflector 920
15.6 Multimedia 923 References 923 Problems 925 16 Smart Antennas 931
16.1 Introduction 931
16.2 Smart-Antenna Analogy 931
16.3 Cellular Radio Systems Evolution 933
16.4 Signal Propagation 939
16.5 Smart Antennas'' Benefits 942
16.6 Smart Antennas'' Drawbacks 943
16.7 Antenna 943
16.8 Antenna Beamforming 946
16.9 Mobile Ad hoc Networks (MANETs) 960
16.10 Smart-Antenna System Design, Simulation, and Results 964
16.11 Beamforming, Diversity Combining, Rayleigh-Fading, and Trellis-Coded Modulation 972
16.12 Other Geometries 975
16.13 Multimedia 976 References 976 Problems 980 17 Antenna Measurements 981
17.1 Introduction 981
17.2 Antenna Ranges 982
17.3 Radiation Patterns 1000
17.4 Gain Measurements 1003
17.5 Directivity Measurements 1010
17.6 Radiation Efficiency 1012
17.7 Impedance Measurements 1012
17.8 Current Measurements 1014
17.9 Polarization Measurements 1014
17.10 Scale Model Measurements 1019 References 1024 Appendix I: f(x) = sin(x) x 1027 Appendix II: f N (x) = sin(Nx) N sin(x) N = 1, 3, 5, 10, 20 1029 Appendix III: Cosine and Sine Integrals 1031 Appendix IV: Fresnel Integrals 1033 Appendix V: Bessel Functions 1035 Appendix VI: Identities 1041 Appendix VII: Vector Analysis 1045 Appendix VIII: Method of Stationary Phase 1055 Appendix IX: Television, Radio, Telephone, and Radar Frequency Spectrums 1061 Index 1065