This book employs a relatively new method for solving electromagnetic problems, one which makes use of a transmission line matrix (TLM). The propagation space is imagined to be filled with this matrix. The propagating fields and physical properties are then mapped onto the matrix. Mathematically, the procedures are identical with the traditional numerical methods; however, the interpretation and physical appeal of the transmission line matrix are far superior. Any change in the matrix has an immediate physical significance. What is also very important is that the matrix becomes a launching pad for many improvements in the analysis, using more modern notions of electromagnetic waves. Eventually, the purely mathematical techniques will probably give way to the transmission line matrix method.Major revisions occur in chapters IV and VII in this second edition. The revised chapters now present an up-to-date and concise treatment on plane wave correlations and decorrelations, and provide a revised formulation of simulation to solve transient electromagnetic problems. It also takes into account semiconductors with arbitrary dielectric constant, using much smaller cell size, and extending the range of applicability and improving accuracy.

This latest edition continues the evolution toward the ultimate realization of a new technique for solving electromagnetic propagation problems. The technique combines the classical and intuitive use of a transmission line matrix (TLM) while striving for consistency with the guideposts demanded by quantum mechanics and the essential structure of electromagnetic theory. The matrix then becomes a useful vehicle for examining both coherent and noncoherent electromagnetic waves. The goal is a mathematical tool capable of solving problems related to the propagation of transient, high-speed, complex waveforms containing both symmetric and plane wave components. For such waveforms, standard classical electromagnetic theory is unable to provide a truly accurate solution since it does not properly account for the correlations among the various TLM cells. The correlations among neighboring TLM cells allow the cell waves to sense one another and to collectively participate as a coherent wave.For arbitrary signals, e.g., complex, high speed, highly non-uniform signals, the correlation model must be placed on a firmer footing to insure the proper correlation strength based on the close adherence to quantum mechanical principles. The purpose of the Third Edition is to thereby improve the correlation model, and incorporate the model into the simulations. The simulation results thus obtained show great promise in describing the full range of electromagnetic phenomena. Wave divergence and diffraction simulations, employing both composite and shorter range correlation models, have been incorporated. The models employ correlation coefficients which may be linked with quantum mechanical parameters, thus providing a deeper understanding of coherent wave fronts.

Summary: Describes transmission line matrix techniques for solving electromagnetic problems. The approach visualizes the propagation medium as divided into identical cells with the electromagnetic energy confined to transmission lines which separate the cells. The author, who works for United Silicon Carbide, develops the electromagnetic scattering equations for one, two and three dimensions, corrects the transmission line matrix for any wave properties, and incorporates boundary conditions and dispersion into the method. Finally, he outlines a computer program for finding the transient solution of a 2D semiconductor switch whose conductivity is induced by a light source.

V. Boundary conditions and dispersion. 5.1. Dielectric-dielectric interface. Node coupling: nearest node and multi-coupled node approximations. 5.2. Nearest nodes for ID interface. 5.3. Nearest nodes at 2D interface. 5.4. Truncated cell and oblique interface. 5.5. Single index cell notation. 5.6. Simplified iteration neglecting the nearest node approximation. 5.7. Non-uniform dielectric. Use of cluster cells. Other boundary conditions. 5.8. Dielectric- open circuit interface. 5.9. Dielectric - conductor interface. 5.10. Input/output conditions. 5.11. Composite transmission line. 5.12. Determination of initial static field by TLM method. 5.13. Time varying source voltage and antenna simulation. Dispersion. 5.14. Dispersion sources. 5.15. Dispersion example. 5.16. Propagation velocity in terms of wave number. 5.17. Dispersive properties of node resistance. 5.18. Node resistance in terms of wave number. 5.19. Anomalous dispersion. Incorporation of dispersion into TLM formulation. 5.20. Dispersion approximations. 5.21. Outline of dispersion calculation using the TLM method. 5.22. One dimensional dispersion iteration. 5.23. Initial conditions with dispersion present. 5.24. Stability of initial profiles with dispersion present. 5.25. Replacement of non-uniform field in cell with effective uniform field -- VI. Cell discharge properties and integration of transport phenomena into the TLM matrix. 6.1. Charge transfer between cells. 6.2. Relationship between field and cell charge. 6.3. Dependence of conductivity on carrier properties. Integration of carrier transport using TLM notation. Changes in cell occupancy and its effect on TLM iteration. 6.4. General continuity equations. 6.5. Carrier generation due to light activation. 6.6. Carrier generation due to avalanching: identical hole and electron drift velocities. 6.7. Avalanching with differing hole and electron drift velocities. 6.8. Two step generation process. 6.9. Recombination. 6.10. Limitations of simple exponential recovery model. 6.11. Carrier drift. 6.12. Cell charge iteraction.equivalence of drift and inter-cell currents. 6.13. Carrier diffusion. 6.14. Frequency of transport iteration. 6.15. Total contribution to changes in carrier cell occupancy -- VII. Description of TLM iteration. 7.1. Specification of geometry. 7.2. Description of inputs and TLM iteration outline. 7.3. Output format. Output simulation data. 7.4. Conditions during simulation. 7.5. Behavior during charge-up.establishment of static field profile. 7.6. Node resistance R(n,m) during activation. 7.7. Output pulse when semiconductor is activated. 7.8. Node recovery and its effect on output pulse. 7.9. Steady state and transient field profiles. 7.10. Partial activation of nodes and effect on profiles and output. 7.11. Cell charge following recovery. 7.12. Role ofTLM waves at charged boundary. 7.13. Comparison of possible boundary conditions at the semiconductor/dielectric interface. 7.14. Simulation results for boundary with non-integral nearest nodes. 7.15. Comparison of output with and without matched input /output lines. 7.16. Simulation of plane wave effects. Effect of alternating input -- VIII. Spice solutions. 8.1. Photoconductive switch. 8.2. Traveling wave Marx generator. 8.3. Traveling Marx wave in a layered dielectric. 8.4. Simulation of a traveling Marx wave in a layered dielectric. Pulse transformation and generation using non-uniform transmission lines. 8.5. Use of cell chain to simulate pulse transformer. 8.6. Pulse transformer simulation results. 8.7. Pulse sources using non-uniform TLM lines (switch at output). 8.8. Radial pulse source (switch at output). 8.9. Pulse sources with gain (PFXL sources). Darlington pulser. 8.10. TLM formulation of Darlington pulser. 8.11. SPICE simulation of Lossy Darlington Pulser.

This comprehensive resource covers both antenna fundamentals and practical implementation strategies, presenting antenna design with optimum performance in actual products and systems. The book helps readers bridge the gap between electromagnetic theory and its application in the design of practical antennas in real products. Practical implementation strategies in products and systems will be addressed in order to design antennas in the context of actual product environments, including PCB layout, component placement and casing design. Practical design examples on wearable electronic products are presented with a systematic approach to designing antennas for actual products. The book introduces antenna fundamentals to provide the basic concepts and necessary mathematics on electromagnetic analysis, followed by advanced antenna elements. The concept of electromagnetic simulation is presented. The advantages and disadvantages of different numerical methods in antenna modeling are also discussed. Several commercial antenna design and simulation tools are introduced, allowing hands-on practice of antenna modeling and simulation.