ABSTRACT
This chapter is devoted to a treatment of two classes of narrowband microwave sources with demonstrated high power capability deep into the millimeter and even sub-millimeter wavelength ranges: gyrotrons and electron cyclotron masers (ECMs), and free-electron lasers (FELs). In fact, in this third edition we focus on the former, for which development continues primarily for CW devices applied to the heating of magnetically confined plasmas; however, this millimeter-wave capability has created a spin-off application for a nonlethal anti-personnel system called the Active Denial System (ADS) (see Chapter 3). Nevertheless, FELs have received considerable attention in the past, and previous efforts have led to the development of a formidable technology base. Unfortunately, they have received little attention as microwave sources in recent years, so that our treatment here constitutes a summary of the more extensive treatment in earlier editions, to which we direct the reader wishing for a more detailed discussion.
