The Book End

Electromagnetic Optimization by Genetic Algorithms
Yahya Rahmat-Samii and Eric Michielssen

John Wiley & Sons Inc.
480 pages; $89.95
ISBN: 0-471-29545-0

Genetic algorithm (GA) optimizers are robust, stochastic search methods modeled on the principles and concepts of natural selection and evolution. GAs are increasingly being applied to traditional and cutting-edge optimization problems in engineering and operations research as well as many nontraditional areas in drug design, financial prediction, data mining and composition of music and poetry. In this book some key features of GAs are presented to facilitate the design of EM devices and applied to the synthesis of various antennas, filters and static devices. The aim of the book is to provide the EM engineer with an up-to-date body of knowledge on the application of GA-based techniques for the optimization and synthesis of EM devices.

The book begins with a section on GA theory and implementation of simple and advanced genetic algorithms. Chapter 1 introduces basic GA nomenclature and describes how a simple GA works. A number of advanced GA schemes and operators are introduced in Chapter 2 along with supporting theory. Chapter 3 details the process of choosing parameters with an example on the design of wire antennas. (Array antenna design is the most widespread application of GAs in electromagnetics.)

Chapters 4, 5 and 6 address the synthesis of thinned, linear and planar arrays and provide a performance comparison between GAs and simulated annealing in the design of arrays. Chapters 7 through 10 demonstrate the use of GAs in the synthesis of broadband wire antennas, strangely shaped wire antennas for circular polarization applications and novel printed antennas. Chapters 11 and 12 describe the application of GAs to the design of various EM filter structures such as waveguide filters, frequency-selective surfaces and all dielectric gratings. Chapter 13 studies the use of a GA in the minimization of an object's radar cross section. The last chapter demonstrates the applicability of GAs in the design of several magnetostatic devices. An extensive bibliography on the application of GAs to the synthesis of EM devices and the solution to inverse problems is also provided.

To order this book, contact:
John Wiley & Sons Inc.,
605 Third Avenue, New York, NY 10158
(800) 225-5945 or (212) 850-6336.

Design of FET Frequency Multipliers and Harmonic Oscillators
Edmar Camargo

Artech House Inc.
215 pages; $83, £62
ISBN: 0-89006-481-4

This book is an introduction to the application of FETs as frequency multipliers and harmonic oscillators. GaAs MESFET technology has become cost competitive to build functions that were traditionally performed by Schottky and varactor diodes and bipolar devices. The book explores the device's nonlinearity to perform multiplication and harmonic generation and emphasizes practical circuit generation as opposed to the physics and mathematics of the subject.

The book begins with an introduction to the application of frequency multipliers in telecommunications systems and the devices used to perform these functions. Nonlinear device modeling is presented in Chapter 2 and the most common analytical approaches are analyzed and compared. Chapter 3 utilizes simple low frequency models to describe multiplier operation. Basic graphical analysis is employed to demonstrate current and voltage waveforms inside the device. Procedures are presented for determining and extracting the basic parameters of frequency multipliers.

Nonlinear high frequency models are considered in Chapter 4 along with a discussion of the effect of parasitics on the gate and drain circuits. Circuit stability is also analyzed and the effect of these reactances on circuit design is demonstrated. Design strategies for nonlinear circuits, including linearization, direct nonlinear synthesis, computer optimization and harmonic load pull, are introduced in Chapter 5. The direct synthesis approach is also described in the design of a frequency tripler.

Chapter 6 concentrates on harmonic oscillator design and describes an application example. Chapter 7 presents a large number of frequency multiplier topologies. Most examples involve discrete component designs, however, examples of commercially available MMICs are also shown.

The numerous illustrative design examples make this book very useful as a reference text or as a supplementary book for graduate students studying nonlinear microwave design and large-signal operation of microwave devices.

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) 171 973 8077.