The term ‘microwaves’ is rather ambiguous, although in exceedingly widespread use. The microwave bands extend from u.h.f. through s.h.f. and e.h.f. Signals at frequencies from around 1Ghz to 100Ghz encompass the bands in question. Above 1Ghz and through millimeter wavelength bands,design tends to be considerably difficult and product more expensive.

Modern microwave engineering involves predominantly circuit analysis and design in contrast to the field theory.Microwave computer-aided design (CAD) software and the network analyser are the essential tools of today’s microwave engineer. The study of microwave engineering must therefore, respond to this shift in emphasis to network analysis, planar circuits and components, and active circuit design. Microwave engineering will always involve electromagnetics, since many of the most sophisticated microwave CAD packages implement rigorous field theory solutions. However the change in emphasis to microwave circuit analysis and design is clear.

Microwave engineering is being used in satellite communication systems and radar.Applications of microwave engineering are now changing, with increasing emphasis on commercial use of microwave technology for personal communications systems, wireless local area networks, millimeter collision avoidance vehicle radars, radio frequency (RF) identification tagging, direct broadcast satellite television and many other systems related to the information infrastructure. These applications demand a critical appreciation of the wide range of devices, circuits and measurement techniques which are available to the system designer.

In the series of future articles on this subject, it is proposed to provide an overview of the various devices, circuits and measurement techniques with the bare minimum of mathematics.