ADAPTIVE DIGITAL FILTER, SIGNAL PROCESSING METHOD, FM RECEIVER, AND PROGRAM

摘要

A complex signal having one signal in a real part and the other signal in an imaginary part, the two signal being generated from one real signal and having phases shifted by 90 degrees from each other, is inputted into an input terminal (301). By a convolution calculation of the input signal and the real signal filter coefficient, a filter unit generates an output signal of a complex signal and outputs it to an output terminal (302). A coefficient control unit is formed by a common section (318) and separate sections (3190 to 319N-1) controls an envelope target value according to the input signal and updates the filter coefficient so that the envelope value obtained from the output signal approaches the envelope target value.