DAVID J. DANIELS, BSC, MSC, CENG, FIET, SMIEE, is the Chief Consultant for Sensors at Cobham Technical Services (formerly known as ERA Technology). David has more than thirty years of experience in the development of radar, acoustic, and electromagnetic systems as well as products for security, sensing, and test applications for the military and commercial enterprises. He has brought such products to market as acoustic detection systems, fiber optic cryogenic liquid leak sensors, marine radar rescue transponders, ultra-wideband microwave amplifiers, ground-penetrating radar, land-mine detectors, and RF and microwave security systems. His current interests center on sensor systems for land-mine detection, homeland security, and military counterterrorist activities.

• Preface xiAcknowledgments xiiiList of Frequently used Acronyms xv1 Introduction 11.1 Scope and Objectives 11.2 Structure 21.3 Market Needs for Security 21.4 Targets inside Containers 51.5 Buried Land Mines 51.6 Forensic Detection of Buried Bodies 61.7 Avalanche and Earthquake Victims 71.8 Concealed Humans 71.9 Concealed Targets on Humans 81.10 Radiological Considerations 81.11 Licensing Considerations 101.12 Statistics of the Detection Performance of a Sensor 121.13 Summary 192 Physics of Propagation 202.1 Introduction 202.2 Propagation of Electromagnetic Fields in Free Space 212.2.1 Reactive Fields 222.2.2 Near Fields 232.2.3 Far Fields 232.2.4 Polarization 242.2.5 Radar Cross Section 272.2.6 Reflection 302.2.7 Refraction 312.2.8 Brewster Angle 312.2.9 Dispersion 332.2.10 Anisotropy 332.2.11 Clutter 332.3 Propagation of Energy in a Dielectric 352.3.1 Introduction 352.3.2 Velocity in a Dielectric 372.3.3 Impedance of a Dielectric 382.3.4 Propagation Loss in a Dielectric 392.3.5 Coupling Losses into Materials 442.4 Dielectric Properties of Soils and Rocks 452.5 Propagation in Water 512.6 Atmospheric Absorption of Electromagnetic Waves 532.6.1 Rain and Fog 552.6.2 Dust, Smoke, and Sand Storms 572.7 Attenuation of Electromagnetic Fields by Materials 592.7.1 Human and Animal 592.7.2 Heartbeat 612.7.3 Respiration 622.7.4 Clothing 662.7.5 Construction Materials 712.7.6 Explosives 762.8 Summary 823 Antennas 833.1 Introduction 833.2 Antenna Parameters 853.2.1 Antenna Directivity 853.2.2 Antenna Gain 863.2.3 Antenna Efficiency 883.2.4 Side Lobes and Back Lobes 883.2.5 Bandwidth 883.2.6 Polarization—Linear, Elliptical, and Circular 893.2.7 Antenna Phase Center 893.2.8 Antenna Patterns 903.2.9 Time Side Lobes and Ring-down 913.2.10 Antenna Footprint 933.3 Aperture Antennas 953.4 Antennas for Proximal Operation 973.4.1 Introduction 973.4.2 Coupling Energy into the Ground or a Dielectric 983.5 Linear Phase Antennas 1013.5.1 Dipoles 1013.5.2 Loaded Antennas 1033.5.3 BiConical Antennas 1063.5.4 Bow-Tie Antennas 1073.5.5 Dielectric Road Antennas 1083.5.6 TEM Horn Antennas 1093.5.7 Impulse Radiating Antennas 1153.6 Nonlinear Phase Antennas 1173.6.1 Vivaldi Antennas 1183.6.2 Equiangular Antennas 1193.6.3 Horn Antennas 1203.7 Antenna Arrays 1213.8 Summary 1264 Nuclear Quadrupole Resonance 1284.1 Introduction 1284.2 Pulse Sequences 1314.3 System Design 1384.3.1 Introduction 1384.3.2 Transmit-and-Receive Coils 1394.3.3 Receiver and Coil Considerations 1434.4 Signal Processing 1444.5 Detection of Explosives 1484.6 Land-Mine Detection 1524.7 Illicit Drugs 1564.7.1 Cocaine 1574.7.2 Cocaine Hydrochloride 1574.7.3 Heroin (Diamorphine) 1584.8 Summary 1625 Radar Systems 1645.1 Introduction 1645.2 Doppler Radar Systems 1645.3 Frequency-Domain Radars 1695.3.1 Introduction 1695.3.2 Two-Frequency Doppler Radar 1705.3.3 Stepped Frequency Radar Systems 1705.3.4 Frequency-Modulated Continuous-Wave Radar 1775.4 Harmonic Radar 1885.5 Noise Radar 1945.6 Spatial Modulation 1985.7 Amplitude Modulation 2025.8 Summary 2136 Passive Systems 2146.1 Introduction 2146.2 Principles of Radiometry 2156.3 Total Power Radiometer 2186.4 Dicke Radiometer 2196.5 Minimum Detectable Temperature 2206.6 Temperature Resolution 2216.7 Imaging Systems 2266.8 Summary 2277 Applications and Technology 2297.1 Introduction 2297.2 Physiological Monitoring 2297.3 Earthquake and Avalanche Radar Systems 2317.4 Forensic Applications 2337.5 Through-Wall Radar (TWR) for Surveillance 2347.6 Harmonic Radar Systems 2407.7 Land-Mine Detection Radar Systems 2407.7.1 Handheld Land-Mine Detection Radar Systems 2407.7.2 Vehicle-Mounted Land-Mine Detection Radar Systems 2437.8 Radar for General Search Operations 2467.9 Spatially Modulated Systems 2487.10 Millimeter-Wave Radar Systems 2487.11 Summary 2538 Summary 254References 260Index 279