Includes bibliographical references and index.

1.1 Where Near-Field Measurements Are Useful 1 -- 1.1.1 Information Provided by Near-Field Maps 1 -- 1.1.2 Near-Field Diagnostics 2 -- 1.1.3 Measurements May Perturb the Near-Fields 2 -- 1.1.4 Modulated Scatterer Approach 2 -- 1.1.5 Basic Requirement 3 -- 1.1.6 Near-to-Far-Field Transformations 3 -- 1.1.7 Two Sets of Applications of Modulated Scatterers 3 -- 1.2 Near-Field Basics 4 -- 1.2.1 Some Definitions for Free-Space Radiation of Antennas 4 -- 1.2.2 Extension to Small Antennas and Circuits 5 -- 1.2.3 About the Near Field Within Inhomogeneous Structures 6 -- 1.2.4 Remark 6 -- 1.3 Various Kinds of Measurements 7 -- 1.3.1 Standard Circuit Measurements 7 -- 1.3.2 Standard Antenna Measurements 7 -- 1.3.3 Direct Near-Field Measurement 8 -- 1.3.4 Perturbation Techniques for Indirect Measurements 9 -- 1.3.5 Cavity Perturbation 9 -- 1.3.6 Perturbation Measurement of SAR in Phantoms 10 -- 1.3.7 Perturbation by a Scatterer 10 -- 1.3.8 Measurement of the Far-Field Pattern of an Antenna 11 -- 1.4 Modulated Scatterer Technique 11 -- 1.4.1 Spinning Dipole 11 -- 1.4.2 Electrically Modulated Scatterer 11 -- 1.4.3 Historical Landmarks 12 -- 1.4.4 Comparison of Direct and Indirect Measurements 13 -- 1.4.5 Tagging Systems and Transponders 13 -- 1.4.6 Biologically Modulated Scatterers 15 -- 1.5 About Computer Simulation And Measurement 17 -- 1.6 Field Maps 18 -- 1.6.1 Microstrip Directional Coupler 18 -- 1.6.2 Printed Patch Antenna 20 -- 1.6.3 Measurements of Large Antennas 22 -- 1.6.4 EMC 24 -- 1.6.5 Dosimetry 25 -- 1.6.6 Microwave Tomography 27 -- Chapter 2 Basic Scatterer Electromagnetics -- 2.1.1 Effects Produced by a Field on a Probe 35 -- 2.1.2 Probe Characteristics in the Receiving Mode 36 -- 2.1.3 Probe Characteristics in the Scattering Mode 36 -- 2.1.4 Bistatic Operation 37 -- 2.1.5 Monostatic Operation 38 -- 2.1.6 Definition of the Nominal Environment 38 -- 2.1.7 Radar Analogy 39 -- 2.1.8 Power Considerations 40 -- 2.1.9 Comparison of Monostatic and Bistatic Operations 40 -- 2.1.10 Practical Considerations 40 -- 2.2 Principle Of Modulated Scattering 41 -- 2.2.1 Modulated Scatterers 41 -- 2.2.2 Mechanically Modulated Scatterers 42 -- 2.2.3 Electrically Modulated Scatterers 43 -- 2.2.4 Optically Modulated Scatterers 44 -- 2.2.5 Light Beam on Photosensitive Material 45 -- 2.2.6 Comparison of the Modulation Schemes 46 -- 2.2.7 Properties of the MST 46 -- 2.3 Equivalent Multiport Representation 47 -- 2.3.1 Equivalent Linear Black Box 47 -- 2.3.2 "Good" and "Bad" Obstacles 48 -- 2.3.3 Matrix Formulations 49 -- 2.3.4 Impedance Matrix 49 -- 2.3.5 Admittance Matrix 50 -- 2.3.6 Relationships Between [Z] and [Y] Matrices 50 -- 2.4 Scattering Matrix Formulation 51 -- 2.4.1 Complex Normalized Waves 51 -- 2.4.2 Scattering Matrix of an N-Port Device 52 -- 2.4.3 Translation of the Reference Planes 52 -- 2.4.4 Relationships Between Matrices 53 -- 2.4.5 Remark 54 -- 2.4.6 Scattering Matrix for the Monostatic Setup (N = 2) 54 -- 2.4.7 Scattering Matrix for the Bistatic Setup (N = 3) 56 -- 2.4.8 Extension to Configurations for Which N> 3 57 -- 2.4.9 Remark About Matrix Formulations 58 -- Chapter 3 Modulated Scattering Probes -- 3.1 Probe Response In Various Situations 61 -- 3.1.1 Probe Response in the Receiving Mode 61 -- 3.1.2 Monostatic Reflection Factor 63 -- 3.1.3 Monostatic Impedance and Admittance Changes 64 -- 3.1.4 Reflection from a Matched Probe 64 -- 3.1.5 Reflection Factor in the Unmodulated Situation 65 -- 3.1.6 Reflection Factor with Mechanical Modulation 65 -- 3.1.7 Reflection Factor with Electrical Modulation 65 -- 3.1.8 Bistatic Transmission Factor 67 -- 3.1.9 Introduction of a Generalized Term 68 -- 3.2 Calculation Of The Probe Response 68 -- 3.2.1 Reciprocity Theorem 68 -- 3.2.2- Reciprocity Formulation 71 -- 3.2.3 Conjugate Matched Probe in the Monostatic Case 73 -- 3.2.4 Reflectionless Matched Probe in the Monostatic Case 73 -- 3.2.5 Modulated Probe in the Monostatic Case 74 -- 3.2.6 Modulated Probe in the Bistatic Case 75 -- 3.3 Free-Space Measurements 76 -- 3.3.1 Locally Plane Waves 76 -- 3.3.2 Absorption Cross Sections 77 -- 3.3.3 RCS for Monostatic Setups 78 -- 3.3.4 Active or Passive Transponder 79 -- 3.3.5 RCS for Bistatic Setups 79 -- 3.4 Probes Used For Near-Field Testing 80 -- 3.4.1 Main Kinds of Probes 80 -- 3.4.2 Small Probes 81 -- 3.4.3 Short Electric Dipoles 81 -- 3.4.4 Small Magnetic Loops 84 -- 3.4.5 Tuned Probes 86 -- 3.4.6 Small Reflecting Spheres 87 -- Chapter 4 Moving Probe Setups -- 4.1 Low Invasiveness 91 -- 4.1.1 Basic Probe Requirements 91 -- 4.1.2 Why a Monostatic Rather Than a Bistatic Configuration? 92 -- 4.1.3 Description of a Measurement Configuration 92 -- 4.1.4 Optical Modulation 93 -- 4.1.5 Low-Frequency Connections with Resistive Wires 94 -- 4.1.6 Coherent Detection 94 -- 4.1.7 Number of Measurement Points 95 -- 4.1.8 About the Measurement Time 95 -- 4.2 Probes For Field Measurements 96 -- 4.2.1 Probes for Direct Antenna Measurements 96 -- 4.2.2 Probes for EMC Measurements 97 -- 4.2.3 Probes for Dosimetry 97 -- 4.2.4 Components of Modulated Scatterer Probes 98 -- 4.2.5 Probe for the Transverse Electric Field 98 -- 4.2.6 Probe for the Normal Electric Field 99 -- 4.2.7 Probe for the Transverse Magnetic Field 100 -- 4.2.8 Optically Modulated Probes 100 -- 4.3 Receivers For MST Arrangements 101 -- 4.3.1 Homodyne Receiver 101 -- 4.3.2 Remark About the Homodyne Receiver's Design 102 -- 4.3.3 Mathematical Background 102 -- 4.3.4 Cancellation of Unmodulated Signals 103 -- 4.3.5 Selection of the Modulation Frequency 104 -- 4.3.6 Signal-to-Noise Ratio 105 -- 4.4 About Measurement Accuracy 106 -- 4.4.1 Spatial Resolution 106 -- 4.4.2 Spurious Signals 108 -- 4.4.3 Close Range Interaction 108 -- 4.4.4 Close Range Interaction with Dielectric 110 -- 4.4.5 Comparison with Simulations 111 -- 4.4.6 Dynamic Range 112 -- 4.4.7 Caution: High Accuracy Is Not Always Required! 113 -- 4.4.8 Scaled Models and the Similitude Theorem 114 -- 4.5 Field Measurements In Materials 115 -- 4.5.1 Impact of Probe Immersion on Measurement Sensitivity 115 -- 4.5.2 Total-Field Measurement with Modulated Probes 116 -- 4.5.3 Total-Field Measurement with Unmodulated Probes 116 -- 4.6 Optical Analogy With Near-Field Microscopy 117 -- 4.6.1 Scanning Near-Field Optical Microscopy 117 -- 4.6.2 Microwave Near-Field Microscopy 118 -- Chapter 5 Applications of Single Probes -- 5.1 Description Of Some MST Test Setups 123 -- 5.1.1 National Physical Laboratory 123 -- 5.1.2 Swiss Ecole Polytechnique Federale of Lausanne 125 -- 5.1.3 University of Michigan at Ann Arbor 126 -- 5.1.4 Other Laboratories 127 -- 5.2 Antenna Diagnostics 128 -- 5.2.1 Horn Antennas 128 -- 5.2.2 Microstrip Patch Antennas 130 -- 5.2.3 Patch Antennas with Parasitic Elements 131 -- 5.2.4 PIFA Dual Band Antennas 132 -- 5.2.5 Multifrequency Multiband Antennas 132 -- 5.2.6 Near-Field Diffraction by Two Slits 133 -- 5.3 Printed Transmission Lines And Circuits 135 -- 5.3.1 Wilkinson Power Dividers 135 -- 5.3.2 Branch Line Hybrid Couplers 135 -- 5.3.3 Rat Race Hybrid Rings 136 -- 5.3.4 Meander Transmission Lines 136 -- 5.3.5 Microstrip Filters with Holes in the Ground Plane 138 -- 5.3.6 MMICs 141 -- 5.3.7 Radiating Probe for Microstrip Integrated Amplifier 141 -- 5.3.8 Currents on a Whisker Mixer for Radiometry 142 -- 5.4 Guiding Structures 144 -- 5.4.1 Detection of Electric-Field Lines in a Liquid Microstrip 144 -- 5.4.2 Fields in a Rectangular Waveguide 146 -- 5.5 EMC 147 -- 5.6 Industrial8 Applications 148 -- 5.6.1 Microwave and RF Heating 148 -- 5.6.2 Industrial Microwave and RF Heating 148 -- 5.6.3 Modulated Scatterer Moisture Sensors 149 -- 5.6.4 Near-Field Measurement in High-Power Systems 149 -- 5.7 Medical Applications And Dosimetry 152 -- 5.7.1 Diathermy and Hyperthermia 152 -- 5.7.2 Portable Phones 152 -- 5.7.3 Measurement of the SAR 153 -- 5.7.4 Radiometric Measurements 154 -- 5.7.5 SAR Measurement of Portable Phones 155 -- 5.7.6 Hyperthermia Applicator and Probe Characterization 157 -- Chapter 6 Probe Arrays -- 6.1.1 Reduction of the Duration of Measurements 161 -- 6.1.2 Reduction of the Amount of Measured Data 162 -- 6.1.3 Speeding Up the Measurement Rate 162 -- 6.1.4 Measurement Strategies 163 -- 6.2 Specific Features Of Probe Arrays 164 -- 6.2.1 Choice of Architectures 164 -- 6.2.2 Preconceptions 166 -- 6.2.3 Probe Array Arrangements 167 -- 6.2.4 Spatial Sampling Requirements 169 -- 6.3 MST For Arrays 170 -- 6.3.1 Array Elements 170 -- 6.3.2 Sensitivity of Collector Arrangements 171 -- 6.3.3 Uniformity of Collector Arrangements 173 -- 6.3.4 Calibrating the Probe Array and Collector Arrangements 176 -- 6.3.5 Practical Bistatic Realizations 178 -- 6.3.6 Different Modulation Possibilities 180 -- 6.3.7 Direct Determination of the Far-Field Pattern 181 -- 6.3.8 Focusing at an Arbitrary Finite Distance 183 -- Chapter 7 Applications of Probe Arrays -- 7.1 Communications And Radar Antenna Testing 187 -- 7.1.1 Antenna Testing Background 187 -- 7.1.2 Near-Field Versus Direct Measurement Techniques 189 -- 7.1.3 Selecting the Proper Near-Field Setup 189 -- 7.1.4 Linear Probe Arrays 191 -- 7.1.5 Planar Probe Arrays 195 -- 7.1.6 Circular Probe Arrays 197 -- 7.1.7 Direct Probing of the Far-Field Pattern 200 -- 7.2 RCS Measurements 202 -- 7.2.1 About Radar Testing 202 -- 7.2.2 Practical Implementation 203 -- 7.3 EMC Testing 205