Automatically adaptive transversal filter

Abstract

A method and apparatus for the adaptive equalizing of phase and amplitude distortion in a received signal by an N-stage digital delay line system and comprising the steps of digitally sampling the received signal and advancing each digital sample through successive stages of the N-stage digital delay line, producing a continuously up-dated scaled error signal after each advance of the digital samples in the delay line, multiplying the digital sample in each delay line stage by the scaled error signal after each sampling advance to produce a first scaled signal in each stage, separately accumulating the first scaled signals of each stage after each sampling advance, scaling and accumulating the accumulations of the first scaled signals of each stage after each M accumulations thereof to produce a weighting tap signal for each stage of the delay line, multiplying the received samples by the weighting tap signal of each stage to produce a weighted sampling for each stage, summing the weighted samplings to produce a summed signal, quantizing the summed signal to a selected quantum value which is selected in accordance with the relative value of the summed signal to the ideal quantum value, and determining and scaling the difference between the summed signal and the quantum value to produce the scaled error signal.