Patent ID: 7196576

Claim:
A control method for a power series predistortion linearizer wherein an input signal is divided and provided to a linear signal transfer path and N odd-order distortion generation paths, N being an integer equal to or greater than 1, and the outputs from said odd-order distortion generation paths are combined into a distortion compensation signal for compensating an intermodulation distortion by a power amplifier, and said odd-order distortion generation paths each have inserted therein a distortion generator for generating an odd-order distortion of said input signal and a frequency characteristic compensator for providing said odd-order distortion with desired frequency characteristics, said method comprising the steps of: (a) inputting a pilot signal and said input signal to said power series predistortion linearizer; (b) extracting distortion components of said pilot signal from the output from said power amplifier; (c) comparing the upper-frequency one of said extracted distortion components of said pilot signal with a reference value, and adjusting frequency characteristics of the gain and phase of said frequency characteristic compensator so that said upper-frequency distortion component of said pilot signal becomes smaller than said reference value; and (d) comparing the lower-frequency one of said extracted distortion components of said pilot signal with said reference value, and adjusting frequency characteristics of the gain and phase of said frequency characteristic compensator so that said lower-frequency distortion component of said pilot signal becomes smaller than said reference value.