Describes applications of time-domain EM reciprocity and the Cagniard-deHoop technique to achieve solutions to fundamental antenna radiation and scattering problems
This book offers an account of applications of the time-domain electromagnetic (TD EM) reciprocity theorem for solving selected problems of antenna theory. It focuses on the development of both TD numerical schemes and analytical methodologies suitable for analyzing TD EM wave fields associated with fundamental antenna topologies.
Time-Domain Electromagnetic Reciprocity in Antenna Modeling begins by applying the reciprocity theorem to formulate a fundamentally new TD integral equation technique - the Cagniard-deHoop method of moments (CdH-MoM) - regarding the pulsed EM scattering and radiation from a thin-wire antenna. Subsequent chapters explore the use of TD EM reciprocity to evaluate the impact of a scatterer and a lumped load on the performance of wire antennas and propose a straightforward methodology for incorporating ohmic loss in the introduced solution methodology. Other topics covered in the book include the pulsed EM field coupling to transmission lines, formulation of the CdH-MoM concerning planar antennas, and more. In addition, the book is supplemented with simple MATLAB code implementations, so that readers can test EM reciprocity by conducting (numerical) experiments. In addition, this text:
- Applies the thin-sheet boundary conditions to incorporate dielectric, conductive and plasmonic properties of planar antennas
- Provides illustrative numerical examples that validates the described methodologies
- Presents analyzed problems at a fundamental level so that readers can fully grasp the underlying principles of solution methodologies
- Includes appendices to supplement material in the book
Time-Domain Electromagnetic Reciprocity in Antenna Modeling is an excellent book for researchers and professors in EM modeling and for applied researchers in the industry.
Table of Contents
Preface xiii
Acronyms xv
1 Introduction 1
1.1 Synopsis 2
1.2 Prerequisites 5
1.2.1 One-Sided Laplace Transformation 6
1.2.2 Lorentz’s Reciprocity Theorem 8
2 Cagniard-Dehoop Method of Moments for Thin-Wire Antennas 15
2.1 Problem Description 15
2.2 Problem Formulation 16
2.3 Problem Solution 18
2.4 Antenna Excitation 20
2.4.1 Plane-Wave Excitation 20
2.4.2 Delta-Gap Excitation 21
Illustrative Example 22
3 Pulsed EM Mutual Coupling Between Parallel Wire Antennas 25
3.1 Problem Description 25
3.2 Problem Formulation 26
3.3 Problem Solution 27
4 Incorporating Wire-Antenna Losses 29
4.1 Modification of the Impedance Matrix 30
5 Connecting a Lumped Element to The Wire Antenna 31
5.1 Modification of the Impedance Matrix 32
6 Pulsed EM Radiation from a Straight Wire Antenna 35
6.1 Problem Description 35
6.2 Source-Type Representations for the TD Radiated EM Fields 36
6.3 Far-Field TD Radiation Characteristics 38
7 EM Reciprocity Based Calculation of Td Radiation Characteristics 41
7.1 Problem Description 41
7.2 Problem Solution 42
Illustrative Numerical Example 43
8 Influence of a Wire Scatterer on a Transmitting Wire Antenna 47
8.1 Problem Description 47
8.2 Problem Solution 48
Illustrative Numerical Example 49
9 Influence of a Lumped Load on EM Scattering of a Receiving Wire Antenna 53
9.1 Problem Description 53
9.2 Problem Solution 54
Illustrative Numerical Example 55
10 Influence of a Wire Scatterer on a Receiving Wire Antenna 59
10.1 Problem Description 59
10.2 Problem Solution 59
Illustrative Numerical Example 61
11 EM-Field Coupling to Transmission Lines 65
11.1 Introduction 65
11.2 Problem Description 68
11.3 EM-Field-To-Line Interaction 68
11.4 Relation to Agrawal Coupling Model 71
11.5 Alternative Coupling Models Based on EM Reciprocity 73
11.5.1 EM Plane-Wave Incidence 73
11.5.2 Known EM Source Distribution 74
12 EM Plane-Wave Induced Thévenin’s Voltage on Transmission Lines 77
12.1 Transmission Line Above the Perfect Ground 77
12.1.1 Thévenin’s Voltage at x = x1 78
12.1.2 Thévenin’s Voltage at x = x2 81
12.2 Narrow Trace on a Grounded Slab 83
12.2.1 Thévenin’s Voltage at x = x1 85
12.2.2 Thévenin’s Voltage at x = x2 88
Illustrative Numerical Example 89
13 VED-Induced Thévenin’s Voltage on Transmission Lines 93
13.1 Transmission Line Above the Perfect Ground 93
13.1.1 Excitation EM Fields 94
13.1.2 Thévenin’s Voltage at x = x1 97
13.1.3 Thévenin’s Voltage at x = x2 98
13.2 Influence of Finite Ground Conductivity 98
13.2.1 Excitation EM Fields 98
13.2.2 Correction to Thévenin’s Voltage at x = x1 100
13.2.3 Correction to Thévenin’s Voltage at x = x2 101
Illustrative Numerical Example 101
14 Cagniard-Dehoop Method of Moments for Planar-Strip Antennas 103
14.1 Problem Description 105
14.2 Problem Formulation 106
14.3 Problem Solution 107
14.4 Antenna Excitation 109
14.4.1 Plane-Wave Excitation 110
14.4.2 Delta-Gap Excitation 111
14.5 Extension to a Wide-Strip Antenna 111
Illustrative Numerical Example 117
15 Incorporating Strip-Antenna Losses 121
15.1 Modification of the Impeditivity Matrix 122
15.1.1 Strip with Conductive Properties 123
15.1.2 Strip with Dielectric Properties 123
15.1.3 Strip with Conductive and Dielectric Properties 124
15.1.4 Strip with Drude-Type Dispersion 124
16 Connecting a Lumped Element to The Strip Antenna 125
16.1 Modification of the Impeditivity Matrix 126
17 Including a Pec Ground Plane 129
17.1 Problem Description 129
17.2 Problem Formulation 130
17.3 Problem Solution 131
17.4 Antenna Excitation 132
Illustrative Numerical Example 133
A Green’s Function Representation in an Unbounded, Homogeneous, and Isotropic Medium 137
B Time-Domain Response of an Infinite Cylindrical Antenna 141
B.1 Transform-Domain Solution 141
B.2 Time-Domain Solution 143
C Impedance Matrix 147
C.1 Generic Integral IA 147
C.2 Generic Integral IB 149
C.3 TD Impedance Matrix Elements 150
D Mutual-Impedance Matrix 151
D.1 Generic Integral JA 151
D.2 Generic Integral JB 153
D.3 TD Mutual-Impedance Matrix Elements 154
E Internal Impedance of a Solid Wire 157
F VED-Induced EM Coupling to Transmission Lines - Generic Integrals 159
F.1 Generic Integral I 159
F.2 Generic Integral J 163
F.3 Generic Integral K 165
G Impeditivity Matrix 169
G.1 Generic Integral J 169
G.1.1 Generic Integral JA 171
G.1.2 Generic Integral JB 175
H A Recursive Convolution Method and Its Implementation 177
H.1 Convolution-Integral Representation 177
H.2 Illustrative Example 179
H.3 Implementation of the Recursive Convolution Method 180
I Conductance and Capacitance of a Thin High-Contrast Layer 183
J Ground-Plane Impeditivity Matrix 187
J.1 Generic Integral I 187
J.1.1 Generic Integral IA 189
J.1.2 Generic Integral IB 193
K Implementation of CDH-Mom for Thin-Wire Antennas 195
K.1 Setting Space-time Input Parameters 195
K.2 Antenna Excitation 197
K.2.1 Plane-Wave Excitation 197
K.2.2 Delta-Gap Excitation 199
K.3 Impedance Matrix 200
K.4 Marching-on-in-Time Solution Procedure 202
K.5 Calculation of Far-Field TD Radiation Characteristics 203
L Implementation of VED-Induced Thévenin’s Voltages on a Transmission Line 205
L.1 Setting Space-Time Input Parameters 205
L.2 Setting Excitation Parameters 206
L.3 Calculating Thévenin’s Voltages 207
L.4 Incorporating Ground Losses 211
M Implementation of CDH-Mom for Narrow-Strip Antennas 215
M.1 Setting Space-Time Input Parameters 215
M.2 Delta-Gap Antenna Excitation 217
M.3 Impeditivity Matrix 217
M.4 Marching-on-in-Time Solution Procedure 200
References 223
Index 227