Abstract: A linearizer particularly valuable for millimeter wave satellite communications is disclosed. A satellite (12) divides signal into linear (20) and nonlinear (32) paths which are converted to finline. A pair of beamlead PIN diodes (48) and a pair of varactor diodes (52) extend across the finline linear path to constitute an attenuator and phase shifter. A pair of anti-parallel Schottky diodes (60) and a pair of PIN diodes (64) extend across the nonlinear path to constitute a limiter and an attenuator. A combiner (30) combines the linear and nonlinear signals for input to an amplifier.

Abstract: A predistortion linearizer (20) is operative with a microwave signal, as may be provided by signal source (62) to linearize the gain of a power amplifier, such as a traveling-wave-tube power amplifier (74), by introduction of an amplitude and/or a phase distortion to the microwave signal wherein the distortion is inverse to a distortion introduced by the power amplifier, thereby to compensate for the distortion of the power amplifier. The linearizer is constructed of two channels (22, 24) which are operated in parallel but approximately 180 degrees out of phase, with an additional phase increment provided by delay lines (46, 56) to offset one channel from the other channel by a phase difference in a range of approximately 160-200 degrees.