Non-metallic materials and composites are now commonplace in modern vehicle construction, and the need to compute scattering and other electromagnetic phenomena in the presence of material structures has led to the development of new simulation techniques.
This book describes a variety of methods for the approximate simulation of material surfaces, and provides the first comprehensive treatment of boundary conditions in electromagnetics. The genesis and properties of impedance, resistive sheet, conductive sheet, generalised (or higher order) and absorbing (or non-reflecting) boundary conditions are discussed. Applications to diffraction by numerous canonical geometries and impedance (coated) structures are presented, and accuracy and uniqueness issues are also addressed, high frequency techniques such as the physical and geometrical theories of diffraction are introduced, and more than i 30 figures illustrate the results, many of which have not appeared previously in the literature.
Written by two of the authorities m the field, this graduate-level text should be of interest to all scientists and engineers concerned with the analytical and numerical solution of electromagnetic problems.
The continuous development of the Geometrical Theory of Diffraction (GTD), from its conception in the 1950s, has now established it as a leading analytical technique in the prediction of high-frequency electromagnetic radiation and scattering phenomena. Consequently, there is an increasing demand for research workers and students in electromagnetic waves to be familiar with this technique. In this book they will find a thorough and clear exposition of the GTD formulation for vector fields. It begins by describing the foundations of the theory in canonical problems and then proceeds to develop the method to treat a variety of circumstances. Where applicable, the relationship between GTD and other high-frequency methods, such as aperture field and the physical optics approximation, is stressed throughout the text. The purpose of the book, apart from expounding the GTD method, is to present useful formulations that can be readily applied to solve practical engineering problems. To this end, the final chapter supplies some fully worked examples to demonstrate the practical application of the GTD techniques developed in the earlier chapters.
This book describes new, highly effective, rigorous analysis methods for electromagnetic wave problems. Examples of their application to the mathematical modelling of micros trip lines, corrugated flexible waveguides, horn antennas, complex-shaped cavity resonators and periodic structures are considered.
Special attention is paid to energy dissipation effects. Various physical models and methods of analysis of dissipation are described and approximate formulas and computer-based calculation results for dissipation characteristics are given and compared with experimental data. Ways of decreasing dissipation in waveguides and resonators are discussed.
The book will be of interest to physicists and engineers working on the theory and design of microwave and millimetre-wave components and devices. Designers in microwave engineering will find here all the information they need for choosing the correct waveguide (resonator) for a stipulated dissipation characteristic. The numerical algorithms and formulas can be directly applied to CAD systems. The book is also relevant for students of electromagnetism and microwave circuits.
This book is an introduction to some of the most important properties of electromagnetic waves and their interaction with passive materials and scatterers. The main purpose of the book is to give a theoretical treatment of these scattering phenomena, and to illustrate numerical computations of some canonical scattering problems for different geometries and materials. The scattering theory is also important in the theory of passive antennas, and this book gives several examples on this topic.
Topics covered include an introduction to the basic equations used in scattering; the Green functions and dyadics; integral representation of fields; introductory scattering theory; scattering in the time domain; approximations and applications; spherical vector waves; scattering by spherical objects; the null-field approach; and propagation in stratified media.
The book is organised along two tracks, which can be studied separately or together. Track 1 material is appropriate for a first reading of the textbook, while Track 2 contains more advanced material suited for the second reading and for reference. Exercises are included for each chapter.
Long before Europeans came to America, the Aztecs created a unique culture based on myth and a love of language. Myths and poems were an important part of their culture, and a successful speech by a royal orator was pronounced "a great scattering of jades." A Scattering of Jades is an anthology of the best of Aztec literature, compiled by a noted anthropologist and a skilled translator of Nahuatl. It is a storehouse of myths, narratives, poems, and proverbs—as well as prayers and songs to the Aztec gods that provide insight into how these people's perception of the cosmos drove their military machine. Featuring a translation of the Mexicayotl—a work as important today for Mexico's concept of nationhood and ideology as it was at the time of the Conquest—these selections eloquently depict the everyday life of this ancient people and their unique worldview. A Scattering of Jades is an unsurpassed window on ancient Mesoamerican civilization and an essential companion for anyone studying Aztec history, religion, or culture.
This book is a systematic and detailed exposition of different analytical techniques used in studying two of the canonical problems, the wave scattering by wedges or cones with impedance boundary conditions. It is the first reference on novel, highly efficient analytical-numerical approaches for wave diffraction by impedance wedges or cones. This text includes calculations of the diffraction or excitation coefficients, including their uniform versions, for the diffracted waves from the edge of the wedge or from the vertex of the cone; study of the far-field behavior in diffraction by impedance wedges or cones, reflected waves, space waves from the singular points of the boundary (from edges or tips), and surface waves; and the applicability of the reported solution procedures and formulae to existing software packages designed for solving real-world high-frequency problems encountered in antenna, wave propagation, and radar cross section. This book is for researchers in wave phenomena physics, radio, optics and acoustics engineers, applied mathematicians and specialists in mathematical physics and specialists in quantum scattering of many particles.
Sea Clutter: Scattering, the K Distribution and Radar Performance, 2nd Edition gives an authoritative account of our current understanding of radar sea clutter. Topics covered include the characteristics of radar sea clutter, modelling radar scattering by the ocean surface, statistical models of sea clutter, the simulation of clutter and other random processes, detection of small targets in sea clutter, imaging ocean surface features, radar detection performance calculations, CFAR detection, and the specification and measurement of radar performance. The calculation of the performance of practical radar systems is presented in sufficient detail for the reader to be able to tackle related problems with confidence. In this second edition the contents have been fully updated and reorganised to give better access to the different types of material in the book. Extensive new material has been added on the Doppler characteristics of sea clutter and detection processing; bistatic sea clutter measurements; electromagnetic scattering theory of littoral sea clutter and bistatic sea clutter; the use of models for predicting radar performance; and use of the K distribution in other fields.
This book provides an authoritative account of the current understanding of radar sea clutter, describing its phenomenology, EM scattering and statistical modelling and simulation, and their use in the design of detection systems and the calculation and practical evaluation of radar performance.
The book pays particular attention to the compound K distribution model developed by the authors during the past 20 years. The evidence for this model, its mathematical formulation and development and practical application to the specification, design and evaluation of radar systems are all discussed. In addition, the book sets the previously empirical development of the K distribution model in the wider context of recent advances in the calculation of low grazing angle electromagnetic scattering and oceanographic modelling of the statistics of the sea surface.
The authors discuss in detail the prediction of the performance of specified radar systems; at the same time, their presentation of the underlying physical principles and analytic and computational techniques employed in these calculations is sufficiently comprehensive for the reader to be well equipped to tackle related problems with confidence.
These features, and appendices reviewing pertinent mathematical background material and the calculation of low grazing angle scattering by corrugated surfaces, make this book invaluable to specialist radar engineers and academic researchers, while being of considerable interest to the wider applied physics and mathematics communities.