RF design can either be understood from first principles through Maxwell's equations (wave theory) or from circuit analysis through the basic passive and active electronic components. This book takes the latter approach because it is much easier and far more practical for building actual circuits. Also the mathematics can be held to a minimum with this approach. One of the main reasons the first edition of this book was so popular was the emphasis on reading and understanding Smith charts. This provides a very quick visual entry into RF design without the heavy emphasis on differential equations and boundary conditions.
The book under review is the second edition, which updates the (now more than 25 years old) first edition with two new chapters on RF Front-End Design (chapter 8) and RF Design Tools (chapter 9). Chapter 8 covers modern radio front-end design including sections on intermodulation, receiver architecture and software defined radios. Chapter 9 gives an overview of design tools before going into a detailed case study of IEEE 802.11a in CMOS using Analog Office software.
It is instructive to see both how many things have changed and yet how the basic principles have remained the same. Even though the individual NPN transistors mentioned in the original chapters are long gone (replaced by highly integrated op-amps and LNAs), the passive components are still used in designs every day. And the transistor design issues (S parameters, transistor biasing) still apply today in the multi-GHz range just as they did in the MHz range a quarter of a century ago. Today's integrated designs might include an on-chip inductor created with rectangular traces wrapped into a "coil" instead of an actual physical coil and on-chip capacitors and resistors, but the principles remain the same. In fact, the performance of passive on-chip capacitors and inductors is normally orders of magnitude worse than is required for high performance designs. Thus the physical components are still widely used today.
There are a number of RF circuit design topics missing from this book, including oscillators, distributed elements, microstrip and slot line designs for GHz ranges and advanced integrated circuit topics for CMOS and GaAs radio design, but these would not fit into an introductory text such as this one. Another item the book doesn't emphasize is the wide variety of online tools available now for RF designers. The website http://rf.rficdesign.com/ has consolidated a number of links to free tools covering many aspects of RF design mentioned in this book, including a Pi Network calculator, S parameter utility and Smith chart Java tool.
In conclusion, this book is ideal for either the RF design hobbyist or professional digital designer who needs to design front end circuits without going back to school. The book has a companion website with high resolution versions of many of the Smith charts in the book, http://books.elsevier.com/companions/defaultindividual.asp?isbn=9780750685184