Feedforward predistortion linearizer

Abstract From the Canadian patent

A feedforward predistortion equalizer includes a first loop with a signal divider for dividing signals into first and second portions, and a distortion generator for distorting the second signal. The first loop is completed by a signal combiner which combines the undistorted first signal and the distorted second signal. The phase and amplitude of the signals in the loop are controlled so that the linear or carrier signal component is cancelled, leaving at the output of the first combiner only the distortion component of the distorted signal. A second loop includes phase and amplitude controls for combining the pure distortion and undistorted signals to produce the desired predistorted …