Adaptive arrays are a radical departure from conventional thinking in antenna design, offering substantial improvements in performance over fixed pattern antennas in environments that include severe interference and jamming. They achieve this because they are designed to steer nulls automatically at noise sources of unknown or variable direction and generally to modify their beampatterns to optimise performance. Adaptive array processing is applicable in most systems that exploit wave propagation; typical uses being radar, active and passive sonar, radio communication links, and radio monitoring. Although sensors and hardware for different applications vary, the same optimality criteria are used throughout and similar algorithms may be employed. This book develops the concepts underlying the design of adaptive arrays from first principles and is directed at research workers and designers whose mathematical background requires refurbishment in the special techniques that have accumulated around the field, often to the obscuration of the simple basic ideas. The topics treated include: single multiple null steering; derivation of the weighting coefficients in an array that maximises signal to noise ratio; online algorithms for achieving these coefficients using gradient methods based on correlators and coefficient peterbation; direct estimation of optimum coefficients by covariance matrix inversion and recursive techniques; prevention of null steering at the desired source and control over the main lobe shape; minimisation of the number of variable coefficients in suboptimal implementations.

This book covers recent achievements in the area of advanced analytical and associated numerical methods as applied to various problems arising in all branches of electromagnetics. The unifying theme is the application of advanced or novel mathematical techniques to produce analytical solutions or effective analytical-numerical methods for computational electromagnetics addressing more general problems. Each chapter contains an outline of its topic, discusses its scientific context and importance, describes approaches to date, gives an exposition of the author's approach to the problem tackled in the chapter, describes the results, and concludes with a discussion of the range or class of problems where the techniques described work most appropriately and effectively. Intended primarily for researchers in the fields of electrical engineering, mathematics, physics and related disciplines, the book offers systematic and thorough coverage of this complex topic. It is hoped that the book will help to stimulate further investigation and discussion of the important problems in electromagnetics within this research community.

Most antennas are assembled from conducting surfaces and wires. The usual approach to numerical analysis of such structures is to approximate them by small surface or wire elements, with simple current approximation over the elements (the so-called subdomain approach), which requires a large amount of computer storage. This book describes a novel general entire-domain method for the analysis of metallic antennas and scatterers which enables the solution of a very wide class of problems to be obtained using computers of relatively modest capability. Antenna-design engineers, scientists and graduate students interested in the analysis and design of electrically small and medium-sized metallic antennas and scatterers will find in this book a self-contained and extremely powerful tool that circumvents most difficulties encountered in other available methods.

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 than130 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.

This exceptional book introduces the reader to the principles, theory and applications of physical layer wireless/mobile communications. applicators and millimetric antennas. The book emphasises the basic principles needed to establish an understanding of this technology, whilst treating the tools required - such as the mathematics and statistics - in the manner of a practical handbook, thus avoiding detailed derivations.

A cognitive radio is a transceiver which is aware of its environment, its own technical capabilities and limitations, and those of the radios with which it may communicate; is capable of acting on that awareness and past experience to configure itself in a way that optimizes its performance; and is capable of learning from experience. In a real sense, a cognitive radio is an intelligent communications system that designs and redesigns itself in real time. Cognitive Radio Engineering is both a text and a reference book about cognitive radio architecture and implementation, intended for readers who want to design and build working cognitive radios. It takes the reader from conceptual block diagrams through the design and evaluation of illustrative prototypes. An important goal is to bridge the divide between radio engineers, who often have little experience with the computational resource and timing issues inherent in cognitive radios, and computer engineers who often are unaware of RF issues like dynamic range, intermodulation products, and acquisition time. Following a brief overview of cognitive radio history and a high-level look at cognitive radio operation, the book presents a detailed study of cognitive engine design and analysis. After treating RF subsystems the book considers computational platforms and computation issues in cognitive radios, followed by system integration, evaluation methods for cognitive radio, and cognitive radio design for networking. The book concludes with coverage of cognitive radio applications in communications.

Corrugated horns are widely used and highly efficient, especially in their use as feeds for microwave reflector antennas. This book is devoted to the theory and design of corrugated horns and scalar feeds and explains why hybrid mode feeds are ideal feeds for reflectors.

Developments in Antenna Analysis and Design presents recent developments in antenna design and modeling techniques for a wide variety of applications, chosen because they are contemporary in nature, have been receiving considerable attention in recent years, and are crucial for future developments. It includes topics such as body-worn antennas, that play an important role as sensors for Internet of Things (IoT), and millimeter wave antennas that are vitally important for 5G devices. It also covers a wide frequency range that includes terahertz and optical frequencies. Additionally, it discusses topics such as theoretical bounds of antennas and aspects of statistical analysis that are not readily found in the existing literature. This first volume covers the theory of characteristic modes (TCM) and characteristic bases; wideband antenna element designs; MIMO antennas; antennas for wireless communication; reconfigurable antennas employing microfluidics; flexible and body-worn antennas; and antennas using meta-atoms and artificially-engineered materials, or metamaterials (MTMs). A second volume covers the topics of: graphene-based antennas; millimeter-wave antennas; terahertz antennas; optical antennas; fundamental bounds of antennas; fast and numerically efficient techniques for analyzing antennas; statistical analysis of antennas; ultra-wideband arrays; reflectarrays; and antennas for small satellites, viz., CubeSats. The two volumes represent a unique combination of topics pertaining to antenna design and analysis, not found elsewhere. It is essential reading for the antenna community including designers, students, researchers, faculty engaged in teaching and research of antennas, and the users as well as decision makers.

Every electric product designed and manufactured worldwide must meet electromagnetic compatibility (EMC) regulations, and yet, EMC compliance staff levels have been cut to the bone in companies large and small. If you are a working engineer or technician, the Electromagnetic Compatibility Pocket Guide: Key EMC Facts, Equations and Data is the first place to look while designing for EMC and your quide to thwarting electromagnetic interference. Key features: Concise, constant-use guide addressing the most common reasons for compliance failure; Get needed answers quickly and move on to other design issues.

This book presents a unified and comprehensive theoretical treatment of electromagnetic, thermal and mechanical phenomena in superconductors. Introduces basic concepts and principles with particular emphasis on general methodology.