Survey and History of the Progress of the Microwave Arts

This is a review of the history and technical progress of the microwave techniques beginning with fundamental research and continuing to present-day practical applications. Particular emphasis is placed on the evolution of techniques that are now of great practical importance. Included are the ordinary 2-wire transmission line and the useful tuning devices that it has provided and also the more recent waveguide techniques which have added not only a new medium of transmission but new antennas for radiating and receiving electromagnetic waves, and a new type of circuitry for dealing with microwaves. Reflecting discontinuities, sometimes conductive and sometimes reactive, when judiciously located inside a waveguide, may perform numerous useful functions such as matching transformers, frequency filters and special networks that very knowingly allow wave power to pass in one direction and not in the reverse. The present paper is a greatly condensed portion of certain chapters of a new book entitled "Forty Years of Radio Research." The latter tells of the author's personal experiences, not only in connection with microwaves, but in connection with the development of much of the rest of the radio spectrum as well.