Microwave Line of Sight Link Engineering

This well written book approaches the subject in a way that a good engineer will find easy to follow. It does not overburden the reader with unnecessary derivations of equations like some text books do, rather it explains the points in a narrative style and then presents equations as required for link design. It is also refreshingly free of jargon and acronyms and contains many high quality diagrams and plots.The book itself starts with a review of fixed links, what they are and how they have developed and in particular why things are as they are due to the evolution of technology and the challenges of propagation. The first chapter covers pretty much the entire field from data formats through network topologies and link budgets to spectrum management. The following chapters then cover the detail, starting with a quick review of propagation. This chapter could have been longer but maybe as this is my field, I am biased and in any case, much more detailed propagation planning is presented in later chapters. Chapter 3 covers frequency planing concisely and comprehensively. Chapter 4 covers the technology, and it is nice to see basic points that are often missed have been included, e.g. modulation and antennas. If there is a criticism this chapter of over 70 pages could have be split into several shorter ones. Chapter 5 covers performance objectives, something I am less familiar with but I round it easy to follow and a useful reference. Chapter 6 - link path engineering basically contains advice on how to make sure a path is line of sight (using modern computer techniques rather than having going out and make a survey) and if it is line of sight, if there are likely to be issues with diffraction and multipath. Chapter 7 covers the ITU-R recommendations which enable the engineer to assess performance impairments due to the atmosphere. It is now slightly out of date as many recommendations referred to have been updated since publication, but the basics are the same. The reader would be advised to download the latest ITU-R recommendations from the website once they have understood the principles in this book. The final chapters are about putting the knowledge gained from previous chapters together. The engineers in us will possibly read these first and look at earlier chapters where a subject is new to us.All in all, it is a good book covering the field comprehensively..

First, disclosure: The publisher offered me a free copy of this text if I would agree to read it and post a review to Amazon.com. Since I design microwave links as part of my job as a consulting engineer, that sounded like a fair deal and I accepted. The book arrived a few days later.As mentioned, I am a consulting engineer, a P.E., and I design radio and TV stations, including the microwave links that broadcasters need to support their operations. If it's RF above 50 MHz or so, I do it. So the opportunity to add a new textbook on microwave engineering to my technical library was attractive, and, who knows, maybe I could learn a few things. I may be an old dog, but I am not adverse to learning new tricks.Microwave Line of Sight Link Engineering is just under 400 pages. It has nine chapters and a 40-page appendix of practical examples. The book has a distinctive non-U.S. Federal Communications Commission (FCC) flavor, citing International Telecommunication Union (ITU) standards extensively. I was a bit puzzled by this until seeing the design examples in the appendix, with geographic coordinates placing the links in South America. Not that there is anything wrong with this: RF propagation doesn't care about international boundaries.The book is black & white, but the graphics are excellent. I learned that a graphical representation of a microwave link's path budget is called a Hypsogram, and that the Fresnel zone radii that have to be considered to ensure adequate path clearances actually have the transmit and receive dishes at the foci of the Fresnel volume. Since that volume is highly elliptical the foci are very near to the ends of the ellipse, and so most diagrams don't bother to show that detail. The Fresnel zone clearance equations are the same, and ones I recognized right away, but this was an interesting detail that I had not been aware of until reading Microwave LoS Link Engineering.The chapter I found most helpful was Chapter 4, which discusses digital modulation from 4-QAM (QPSK) through 516-QAM (which would make me nervous for even an engineered RF path with lots of fade margin); higher level QAMs are pretty fragile signals. Great for pushing through fiber optic or coaxial cables, but in my view iffy for anything except the most robust of microwave paths. The Figure 4.19 depiction of adaptive modulation is the best graphic I have seen anywhere demonstrating the concept. And, in the U.S., the FCC has only recently decided to routinely allow adaptive modulation (it's a path efficiency issue, and one that can unfortunately be abused).This text is a nice addition to my technical library, and an excellent resource for sorting through the multitude of ITU recommendations. Although those recommendations are generally not binding for microwave links in the United States, which instead are subject to FCC regulations, it was good to now have a convenient reference for those documents.This would be a good text for an undergraduate EE course on microwave engineering, or for an IT professional getting dragged into doing "just a couple" of short microwave hops between buildings, or cell site backhaul links. Mr. Romo and Mr. Angueira get a "well done" and my thumbs up positive recommendation for their book.