ABSTRACT
In the introductory chapter it was noted that microwaves encompass a wide sphere of applications owing to their many inherent advantages. The study of microwave systems and devices requires the proper understanding of plane waves, transmission lines and related topics that are based on field theory. In general, these topics are included in the curriculum of electromagnetics given at a lower level. Since the concepts involved in these form the basis for microwaves, this chapter summarises some of the essential aspects of wave propagation in free space, between parallel planes and in transmission lines.
