Electromagnetic Fields in Cavities

The first book of its kind, Electromagnetic Fields in Cavities presents a unique combination of rigorous solutions to Maxwell's equations with conservation of energy to solve for the statistics of many quantities of interest: penetration into cavities (and shielding effectiveness), field strengths far from and close to cavity walls, and power received by antennas within cavities. Including all modes, rather than just the dominant mode, as well as wall losses and a special treatment of the current source region, the book is a valuable tool for researchers, practicing engineers, professors, and graduate students.

InhaltsangabePREFACE. PART I. DETERMINISTIC THEORY. 1. Introduction. 1.1 Maxwell's Equations. 1.2 Empty Cavity Modes. 1.3 Wall Losses. 1.4 Cavity Excitation. 1.5 Perturbation Theories. Problems. 2. Rectangular Cavity. 2.1 Resonant Modes. 2.2 Wall Losses and Cavity Q. 2.3 Dyadic Green's Functions. Problems. 3. Circular Cylindrical Cavity. 3.1 Resonant Modes. 3.2 Wall Losses and Cavity Q. 3.3 Dyadic Green's Functions. Problems. 4. Spherical Cavity. 4.1 Resonant Modes. 4.2 Wall Losses and Cavity Q. 4.3 Dyadic Green's Functions. 4.4 Schumann Resonances in the Earth-Ionosphere Cavity. Problems. PART II. STATISTICAL THEORIES FOR ELECTRICALLY LARGE CAVITIES. 5. Motivation for Statistical Approaches. 5.1 Lack of Detailed Information. 5.2 Sensitivity of Fields to Cavity Geometry and Excitation. 5.3 Interpretation of Results. Problems. 6. Probability Fundamentals. 6.1 Introduction. 6.2 Probability Density Function. 6.3 Common Probability Density Functions. 6.4 Cumulative Distribution Function. 6.5 Methods for Determining Probability Density Functions. Problems. 7. Reverberation Chambers. 7.1 PlaneWave Integral Representation of Fields. 7.2 Ideal Statistical Properties of Electric and Magnetic Fields. 7.3 Probability Density Functions for the Fields. 7.4 Spatial Correlation Functions of Fields and Energy Density. 7.5 Antenna or Test-Object Response. 7.6 Loss Mechanisms and Chamber Q. 7.7 Reciprocity and Radiated Emissions. 7.8 Boundary Fields. 7.9 Enhanced Backscatter at the Transmitting Antenna. Problems. 8. Aperture Excitation of Electrically Large, Lossy Cavities. 8.1 Aperture Excitation. 8.2 Power Balance. 8.3 Experimental Results for SE. Problems. 9. Extensions to the Uniform-Field Model. 9.1 Frequency Stirring. 9.2 Unstirred Energy. 9.3 Alternative Probability Density Function. Problems. 10. Further Applications of Reverberation Chambers. 10.1 Nested Chambers for Shielding Effectiveness Measurements. 10.2 Evaluation of Shielded Enclosures. 10.3 Measurement of Antenna Efficiency. 10.4 Measurement of Absorption Cross Section. Problems. 11. Indoor Wireless Propagation. 11.1 General Considerations. 11.2 Path Loss Models. 11.3 Temporal Characteristics. 11.4 Angle of Arrival. 11.5 Reverberation Chamber Simulation. Problems. APPENDIX A. VECTOR ANALYSIS. APPENDIX B. ASSOCIATED LEGENDRE FUNCTIONS. APPENDIX C. SPHERICAL BESSEL FUNCTIONS. APPENDIX D. THE ROLE OF CHAOS IN CAVITY FIELDS. APPENDIX E. SHORT ELECTRIC DIPOLE RESPONSE. APPENDIX F. SMALL LOOP ANTENNA RESPONSE. APPENDIX G. RAY THEORY FOR CHAMBER ANALYSIS. APPENDIX H. ABSORPTION BY A HOMOGENEOUS SPHERE. APPENDIX I. TRANSMISSION CROSS SECTION OF A SMALL CIRCULAR APERTURE. APPENDIX J. SCALING. REFERENCES. INDEX.

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