Linearizer bridge circuit

摘要

A Ku-band integrated predistortion type linearizer bridge circuit for use in linearizing the performance of a travelling wave tube amplifier (20). The linearizer bridge circuit comprises a linearizer bridge that embodies a phase shifter (23) and a fixed delay (22a) in a linear arm (21a), and a Schottky diode distortion generator (24a) and a PIN diode attenuator (25) in a nonlinear arm (21b). The output of the linearizer bridge is coupled through an output amplifier (32) and an output attenuator (33). The RF output signal from the linearizer bridge circuit is coupled to the travelling wave tube amplifier (20). A control circuit (35) is coupled to the phase shifter (23), the nonlinear Schottky diode distortion generator circuit (24A), and the PIN diode attenuator (25), and receives on and off input command signals, and outputs a bilevel telemetry signal that is used as a mode indicator for ground command control. The control circuit (35) is used to adjust settings of the Schottky diode distortion generator (24A), the phase shifter (23), the PIN diode attenuator (25), and adjust the gain and attenuation settings of the output amplifier (32) and output attenuator (33). All circuits of the linearizer bridge circuit are integrated onto a single alumina substrate (26). <IMAGE>