* Dynamic Electromagnetics
Paul Diament
Prentice Hall
497 pages; $100
ISBN: 0023287-60-8
S ome people think the study of electromagnetics is nasty. However, the author sets out to simplify the study of dynamic electromagnetics and has written a text that provides the framework for a one-semester first course in electromagnetics for engineers and physicists. (It is the only required electromagnetics undergraduate course at Columbia University.)
The author's approach uses time-varying fields as the central and paramount place to start. The emphasis is on distributed systems, where time development and dynamics are deeply involved, as opposed to the classic concentration on statics. The book uses simple mathematics at the level of integral calculus and steers away from partial differential equations and boundary value problems. The text makes extensive use of Maxwell's equations in integral form.
The text approaches high frequency phenomena using quasistatic analysis, thus providing a more user-friendly transition from low frequency circuit theory. The main focus of the course work is on wave propagation, exemplified by the behavior and response of transmission lines in both transient and steady state.
Both electric and magnetic fields are treated with virtually equal importance, and the book emphasizes how one affects, creates and maintains the other. In addition, the text avoids introducing potentials and the notion that the electric field is the gradient of a scalar potential. Potentials are considered a major obstacle to making the transition to the time-varying case. Voltages are dealt with, but as electromotive forces, not as potentials.
The examples provided in the text are extensively discussed and interpreted, well beyond the determined solution. In some cases guidance as to how to prove a theory has been left to the problems as a better means of demonstrating the points.
If a textbook on dynamic electromagnetics can be considered refreshing, this book fits the bill. It presents a nasty subject in a much more favorable light, and attempts to make learning the material much less intimidating.
To order this book, contact: Prentice Hall, PO Box 11073, Des Moines, IA 50336 (800) 947-7700.
* Electronic Warfare in the Information Age
D. Curtis Schleher
Artech House Inc.
605 pages plus diskette; $105, £72
ISBN: 0-89006-526-8
E lectronic warfare (EW) is basically a battle for control of the EM spectrum. It is recognized that a primary function of the EM spectrum is as a carrier of information, which is essential to any military operation. New EW definitions include electronic attack (EA), electronic support (ES) and electronic protection (EP). Thus, the new EW is both offensive and defensive, and involves denying the enemy use of critical information as well as the preservation of our own. This book describes the new functions of EW in terms of today's communications revolution.
The book begins by describing the new and continuing functions of EW, including a discussion of jamming of modern communications nets. Chapter 2 goes on to describe several advanced radar techniques that have created stress for older EW systems. Chapter 3 describes the architecture and capabilities of modern EA systems and the trend toward off-board systems to cope with the monopulse radar threat.
Chapter 4 focuses on EA actions directed against modern radars with advanced capabilities, including techniques used against pulse compression, pulsed Doppler, monopulse and sidelobe cancellation threat systems. Chapter 5 provides a complete description of digital RF memories, an essential component in the design of modern EA systems. Chapter 6 discusses advanced ES systems, including advanced receiver and processing systems. The optimum receiver for these applications is the digital receiver, which separates the signal set into individual channels where each signal can be further analyzed. Chapter 7 covers expendables and decoy systems, a system that is becoming increasingly popular. Infrared missile attach is also discussed. The final chapter discusses directed energy weapons and signature control.
EW techniques are rapidly changing in light of the new information age capabilities. This book brings EW up to date and makes the reader aware of the many new threats that exist today and what is being done to counter those threats.
To order this book, contact: Artech House Inc., 685 Canton St., Norwood, MA 02062 (781) 769-9750, ext. 4002; or 46 Gillingham St., London SW1V 1HH, UK +44 (0)20 7596-8750.