Monolithic GaAs FET Power Amplifiers for Kₐ Band

A program to demonstrate the feasibility of GaAs-based K-band power amplifiers has generated a number of technological advances. The goals of the program included (1) capability of amplifier operation at center frequencies of 23, 29, and 32.5 GHz; (2) bandwidth of 5 percent at each center frequency; and (3) gains and output power levels as specified in the table. Each amplifier was to contain three metal/semiconductor field-effect transistor (MESFET) stages, the MESFET gate width in each stage being larger than that of the preceding stage (see figure). During the program, one- and two-stage amplifier submodules with various input and output network configurations were also constructed and tested to characterize the input, output, and interstage-matching electrical characteristics of the networks.