Microwave Radio Links, from Theory to Design

Carlos Salema
Wiley Interscience
474 pages; $79.95
ISBN: 0-471-42026-3

This book introduces the reader to the principles and the design of microwave links. It can be used as a textbook for upper level engineering students and a reference for the practicing engineer. It discusses thoroughly the subject of microwave links, from the basic concepts of free space propagation and aperture antennas, through the transmission of analog and digital signals in noisy (and fading) channels, right to the design specifications and costing of links.

After a brief historic review, Chapter 1 describes a typical microwave radio link, introduces the techniques and the hardware, and presents the principles upon which frequency plans are based. Chapter 2 deals with propagation in the atmosphere in stable conditions, that is, in conditions which are valid, on average, for at least 10 seconds, including the effects of the presence of the earth, obstacles, atmospheric gases and rain. Although the emphasis is on line-of-sight links and links with propagation by diffraction, troposcatter links are referred to briefly. Varying propagation conditions, leading to fading, and diversity techniques to counteract fading are described in Chapter 3. Chapters 4 and 5 are devoted to link performance, as a function of the received power, for analog and digital links, respectively, in accordance to the applicable recommendations for international links. Chapter 6 deals with error control codes, which are becoming increasingly popular in digital links as a measure to continuously monitor link performance and, in some cases, to correct transmission errors.

Finally, in Chapter 7, the principles and theory presented in the previous chapters are applied and the reader is introduced to the design of microwave radio links. Three appendices are included, which discuss detailed frequency plans for the main microwave bands, the derivation of the output signal-to-noise ratio for frequency and phase demodulators as a function of the input carrier to noise ratio, typical costs of microwave radio links components and link calculations for a typical microwave radio link.

To order this book, contact: John Wiley & Sons Inc., One Wiley Drive, Somerset, NJ 08875 (800) 225-5945.

Nonlinear Microwave and RF Circuits, Second Edition

Stephen A. Maas
Artech House Inc.
582 pages; $99, £69
ISBN: 1-58053-484-8

This is the second edition, revised and expanded, of the very successful Nonlinear Microwave Circuits, published in 1988. During the past fifteen years, nonlinear circuit technology has advanced considerably, with the help of much more powerful personal computers and the introduction of new semiconductor devices. The word RF has been added to the title to show the change in direction the technology has incurred since the first edition. RF, wireless and cellular systems depend strongly on hetero-junction bipolar transistors, a technology that has grown to maturity since the first publication. Similarly, power MOS devices, known as VHF/UHF transistors in 1988, are extremely important for power applications in the low end of the microwave range. While the MESFET was the only real option for microwave transistors in 1988, now high performance HEMT devices for both power and small-signal applications are available.

While the book has been almost completely rewritten to update the technical information, its organization has remained unchanged. Chapter 2, on device modeling, now includes the new devices. Chapter 3, on harmonic balance, has been considerably lengthened to include the latest developments. Chapter 4, "Volterra-series and Power Analysis," and Chapter 5, "Balanced and Multiple-device Circuits," have been kept practically the same. The last seven chapters, which are design oriented, are completely new. In particular, the design examples have been brought up to date to show how modern circuit analysis software can be best exploited to produce state-of-the-art components. Chapters 6 and 7 are dedicated to diode mixers and diode frequency multipliers, respectively. Small-signal amplifiers and power amplifiers are the subjects of Chapters 8 and 9. Chapter 10 covers active frequency multipliers while Chapter 11 describes active mixers and FET resistive mixers. Transistor oscillators are the subject of Chapter 12.

To order this book, contact: Artech House Inc., 685 Canton St., Norwood, MA 02062 (781) 769-9750 ext. 4030; or 46 Gillingham St., London SW1V 1HH, UK +44 (0) 207 596-8750.