Distortion compensation circuit and transmitter using distortion compensation circuit and high-frequency power amplifier

摘要

In order to shorten the convergence time for compensating distortion generated by a high-frequency power amplifier, a distortion compensation circuit which independently generates coefficients of odd-symmetrical amplitude distortion compensation signals and coefficients of odd-symmetrical phase distortion compensation signals of respective orders of a high-frequency power amplifier includes an even-symmetrical distortion compensation signal generation circuit for generating an even-symmetrical amplitude distortion compensation signal and an even-symmetrical phase distortion compensation signal from a difference between the input signal amplitude and a signal obtained by delaying the input signal amplitude and a difference between the input signal and a signal obtained by delaying the input signal, respectively independently and independently of the odd-symmetrical distortion compensation signals, and an even-symmetrical distortion compensation signal superposition circuit for superposing the even-symmetrical distortion compensation signals on the input signal, and conducts pre-compensation on odd-symmetrical distortion and even-symmetrical distortion independently.