ANTENNA THEORY part 2

Transcription

1 Inter-University Electronics Series, Vol. 7 ANTENNA THEORY part 2 Robert E. Collin Division of Electrical Sciences and Applied Physics Case Western Reserve University Cleveland, Ohio Francis J. Zucker Air Force Cambridge Research Laboratories L. G. Hanscom Field Bedford, Massachusetts McGraw-Hill Book Company New York St. Louis San Francisco London Sydney Toronto Mexico Panama

2 Foreword Preface v vii CONTENTS CHAPTER 16 WAVE FRONTS, RAYS, AND FOCAL SURFACES F. Sheppard Holt 16.1 Introduction The Eikonal and the Eikonal Equation Geometrical Optics as a Zero-wavelength Approximation Fermat's Principle and Snell's Laws Phase Analysis and Phase Synthesis Power Flow in Ray Tubes Power Distribution in the Aperture Power Distribution in the Focal Region Power Distribution in the Far Field Reflection from a Conducting Surf ace Ray Collimation and Off-focus Feeding Congruences and the Equal-path-length Law Focal Surfaces General Comments on Focal Surfaces 28 Appendix A: Principal Normal Radii of Curvature, Principal Directions, Principal Planes, and Lines of Curvature 30 Appendix В: Geometrical Optics Power Flow in a Source-free, Nonconducting, Isotropic, Homogeneous Medium 31 Problems 33 References 34 CHAPTER 17 REFLECTOR С J. Sletten 17.1 Importance of Reflector Antennas Types of Reflector Antennas and Their Primary Uses The Paraboloid with Source at the Focus The Wide-angle or Off-focus Characteristics of Paraboloids Techniques for Compound Primary-feed Designs Spherical Reflector Cylindrical Reflector Antennas Parabolic Torus Antennas Stepped Reflector Antennas Multiplate Antenna The Corner Reflector Antenna 96 Problems 101 References 101 xi

3 Xll CONTENTS CHAPTER 18 LENS John Brown 18.1 Introduction Artificial Dielectrics Design of Homogeneous Lenses Lenses for Beam-scanning Applications Extension of Scanning Analysis Nonhomogeneous Lenses Configuration Lenses Discussion 144 Problems 145 References 149 CHAPTER 19 GENERAL CHARACTERISTICS OF TRAVELING-WAVE Alexander Hessel 19.1 Introduction Modal Properties of Uniform Traveling-wave Structures The Dispersion Relation for Shielded Waveguides Guided Waves on Planar Open Structures The Excitation Problem in Traveling-wave Structures Characteristics of Specific Guided Waves Guided Waves on Periodically Loaded Traveling-wave Structures The Brillouin Diagram and Mode Coupling in Closed Periodic Structures Guided Waves on Radiating, Periodically Loaded, Traveling-wave Structures Kinematic Properties Spectral Properties of Spatial Harmonics Guided Waves in Radiating, Periodically Loaded, Traveling-wave Structures Dynamic Properties Examples of Brillouin Diagrams of Periodically Loaded, Radiating, Travelingwave Structures 225 Appendix A: Review of Modal Formalism 235 Appendix В: The Square Root Function in the Complex k z Plane 238 Appendix C: The Transformation к г = k 0 sin w 241 Appendix D: The Spectral Representation of the Field of a Magnetic Line Source above an Inductive Surface Reactance Plane 242 Appendix E: Some Properties of the Dispersion Relation of Lossless, Planar, Periodic, Open, Traveling-wave Structures 246 Appendix F: The principal Branch of Solutions of the Dispersion Relation for SM RS at ßod = Sir 248 Problems 250 References 255

4 CONTENTS xiii CHAPTER 20 LEAKY-WAVE Т. Tamir 20.1 Introduction The Field of a Leaky-wave Distribution Radiation-pattern Calculations The Complex-angle Plane w and Its Relation to the Leaky-wave Field Control of Aperture Distribution Determination of the Complex Wave Number k z Specific Antenna Structures 289 Problems 295 References 295 CHAPTER 21 SURFACE-WAVE Francis J. Zucker 21.1 Introduction to Surface Waves How Does a Surface-wave Antenna Radiate? Surface-wave Excitation Discontinuities and Tapers Surface-wave Structures 331 Appendix: Saddle-point Integration 338 Problems 341 References 343 CHAPTER 22 LOG-PERIODIC R. Mittra 22.1 Historical Introduction Principle of Scaling and Application to Log-periodic Design Application of k-ß Diagrams to Log-periodic Antenna Analysis Other Approaches to the Analysis of Log-periodic Structures Transient Response of Log-periodic Antennas 378 Appendix A: Solution of Equations for P(ct) and Q(a) Appearing in Sec d 380 Appendix В: The Expressions for the Far Field of a Conical Spiral Antenna 382 Problems 383 References 384 CHAPTER 23 CHARACTERISTICS OF OVER LOSSY EARTH James R. Wait 23.1 Fields of Elementary Dipoles over a Homogeneous Half Space Radiation Resistance and Impedance Increments Resulting from the Presence of the Homogeneous Half Space 392

5 xiv CONTENTS 23.3 Characteristics of a Thin Linear Antenna over the Conducting Half Space Linear Antenna over a Solid Metal Disk Which Is Lying on the Half Space Radial Wire Ground Systems Influence of the Ground Plane on Antenna Patterns Conclusions 435 References 435 CHAPTER 24 ELECTROMAGNETIC FIELDS OF SOURCES IN LOSSY MEDIA James R. Wait 24.1 Introduction The Infinitesimal Radiating Sources in a Lossy Medium The Finite Current Element The Horizontally Stratified Earth Electric Dipole inside a Two-layer Earth The Infinite Wire over the Three-layer Earth Grounded Wires on the Homogeneous Earth Self-impedance of Circuits in a Dissipative Medium 495 Appendix A: Plane Wave Transient Propagation 502 Appendix В: Evaluation of Integrals 505 References 506 CHAPTER 25 IN PLASMA James R. Wait 25.1 Introduction and Basic Considerations Radiation from a Current Distribution in an Isotropic Electron Plasma Application to a Cylindrical Antenna The Cylindrical Shell Model Collected Results Boundary-value Approaches to Antennas in Plasma Media Influence of the DC Magnetic Field Concluding Remarks 551 References 553 CHAPTER 26 THE ANTENNA AS A SPATIAL FILTER 26.1 Introduction Spatial Frequency Analysis 557 A. C. Schell

6 CONTENTS XV 26.3 The Distinction between Coherence and Incoherence The Incoherent Source Antenna Transfer Function Different Antenna Types and Their Spatial Frequency Responses Optimizing System Performance Optimizing Incoherent Source Transfer Functions Data Processing Angular Resolution Enhancement 574 Problems 577 References 578 CHAPTER 27 SIGNAL-PROCESSING A. A. Ksienski 27.1 Introduction Definition and Description of Multiplicative Arrays Response of Linear and Nonlinear Multiplicative Antennas to General Source Distributions Performance of Multiplicative Arrays in the Presence of Noise Multiple Correlation Arrays Aperture Synthesis Applications of Multiplicative Arrays Pattern Multiplication by Two-way Mode of Operation Definition and Description of Synthetic Array Radar Synthetic Array Pattern Parametric Design Considerations of Synthetic Array Radar Unfocused Synthetic Arrays Focused Synthetic Arrays Recording and Optical Processing in Synthetic Array Radar The Optical Properties of the Records Performance Degrading Factors of Synthetic Array Radar Detection Methods 643 Problems 650 References 651 CHAPTER 28 LARGE ANTENNA SYSTEMS Merrill I. Skolnik 28.1 Introduction Limitations to Antenna Size Large Antennas Examples 665 Problems 673 References 673 Bibliography 675 Index 677