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Informationen zum Autor THOMAS A. MILLIGAN is Chief Engineer for Milligan & Associates, Inc., a consulting firm that offers wireless communications solutions. He previously was principal engineer at Lockheed Martin Astronautics, where he specialized in microwave antenna design and analysis. Mr. Milligan is the author of the first edition of Modern Antenna Design and coauthor of Antenna Engineering Using Physical Optics. Klappentext * A practical book written for engineers who design and use antennas* The author has many years of hands on experience designing antennas that were used in such applications as the Venus and Mars missions of NASA* The book covers all important topics of modern antenna design for communications* Numerical methods will be included but only as much as are needed for practical applications Zusammenfassung Written by expert antenna designers, Modern Antenna Design, Second Edition presents essential material necessary for practitioners to accomplish their work. The book provides the theory of antennas and distills it to the parts needed to design, specify, and use antennas. Inhaltsverzeichnis Preface xv 1 Properties of Antennas 1 1-1 Antenna Radiation 2 1-2 Gain 3 1-3 Effective Area 6 1-4 Path Loss 6 1-5 Radar Range Equation and Cross Section 7 1-6 Why Use an Antenna? 9 1-7 Directivity 10 1-8 Directivity Estimates 11 1-8.1 Pencil Beam 11 1-8.2 Butterfly or Omnidirectional Pattern 13 1-9 Beam Efficiency 16 1-10 Input-Impedance Mismatch Loss 17 1-11 Polarization 18 1-11.1 Circular Polarization Components 19 1-11.2 Huygens Source Polarization 21 1-11.3 Relations Between Bases 22 1-11.4 Antenna Polarization Response 23 1-11.5 Phase Response of Rotating Antennas 25 1-11.6 Partial Gain 26 1-11.7 Measurement of Circular Polarization Using Amplitude Only 26 1-12 Vector Effective Height 27 1-13 Antenna Factor 29 1-14 Mutual Coupling Between Antennas 29 1.15 Antenna Noise Temperature 30 1-16 Communication Link Budget and Radar Range 35 1-17 Multipath 36 1-18 Propagation Over Soil 37 1-19 Multipath Fading 39 References 40 2 Radiation Structures and Numerical Methods 42 2-1 Auxiliary Vector Potentials 43 2-1.1 Radiation from Electric Currents 44 2-1.2 Radiation from Magnetic Currents 49 2-2 Apertures: Huygens Source Approximation 51 2-2.1 Near- and Far-Field Regions 55 2-2.2 Huygens Source 57 2-3 Boundary Conditions 57 2-4 Physical Optics 59 2-4.1 Radiated Fields Given Currents 59 2-4.2 Applying Physical Optics 60 2-4.3 Equivalent Currents 65 2-4.4 Reactance Theorem and Mutual Coupling 66 2-5 Method of Moments 67 2-5.1 Use of the Reactance Theorem for the Method of Moments 68 2-5.2 General Moments Method Approach 69 2-5.3 Thin-Wire Moment Method Codes 71 2-5.4 Surface and Volume Moment Method Codes 71 2-5.5 Examples of Moment Method Models 72 2-6 Finite-Difference Time-Domain Method 76 2-6.1 Implementation 76 2-6.2 Central Difference Derivative 77 2-6.3 Finite-Difference Maxwell's Equations 77 2-6.4 Time Step for Stability 79 2-6.5 Numerical Dispersion and Stability 80 2-6.6 Computer Storage and Execution Times 80 2-6.7 Excitation 81 2-6.8 Waveguide Horn Example 83 2-7 Ray Optics and the Geometric Theory of Diffraction 84 2-7.1 Fermat's Principle 85 2-7.2 H -Plane Pattern of a Dipole Located Over a Finite Strip 85 2-7.3 E-Plane Pattern of a Rectangular Horn 87 2-7.4 H -Plane Pattern of a Rectangular Horn 89 2-7.5 Amplitude Variations Along a Ray 90 2-7.6 Extra Phase Shift Through Caustics 93 2-7.7 Snell's...
