FEEDFORWARD AMPLIFIER WITH REDUCED DISTORTION IN WIDE BAND

摘要

A first pilot signal is superimposed onto an inputsignal to thereby distribute the signal as a first signal anda second signal to two destinations. The first signal is fedvia an equalizer to a main amplifier for amplificationthereof such that a second pilot signal is mixed with theamplified signal to attain a main amplification signal.Subtraction is conducted between the second signal and themain amplification signal to extract a distortion signal tobe fed via an equalizer to an auxiliary amplifier so as toproduce an auxiliary amplification signal. Between the mainand auxiliary amplification signals, there is effectedsubtraction to attain a differential signal. The pilotsignals are detected according to the differential and outputsignals. The equalizers are controlled to set the pilotsignals to a minimum value. Consequently, there is achieveda linear amplifier obtaining a stable amplification signalwith reduced distortion in a wide band.