To control a signal passband without increasing the number of taps.

The signal processing apparatus includes: an analysis signal-generating section that converts a digital signal into an analysis signal of a complex number, using a digital filter; and a compensation section that compensates for the analysis signal, using a compensation coefficient of a complex number in accordance with non-linear distortion, wherein the digital filter divides data of the digital signal into (n) data sequences (n is an integer ≥2), allocates (n×L+k)th data (L=0, 1, ...) of the digital signal to a k-th data sequence (k=1, 2, ..., n), filters the respective data sequences using the same filter coefficient, and combines the respective filtered data sequences to generate an imaginary number portion of the analysis signal.