Ka-band monolithic GaAs two-stage power amplifier

The development of a Ka-band monolithic GaAs two-stage power amplifier with 3.6-mm total gate width is presented. The monolithic amplifier uses FETs with 1.2-mm and 2.4-mm gate widths for the first-stage and second-stage devices, respectively. It delivers an output power of 0.56 W, with a power gain of 7.2 dB, and a power-added efficiency of 15% at 28 GHz. Output power of more than 0.5 W is obtained over 27.5-28.5 GHz, with power gain exceeding 5 dB. The authors expect that further improvements in output power will be achieved through drain current optimization and a monolithic parallel combining of amplifiers.<<ETX>>