DISTORTION COMPENSATION DEVICE AND DISTORTION COMPENSATION METHOD

摘要

A compensation data table (304) generates information on non-linear characteristic of a base band signal. A judgment section (305) judges whether the power has increasing tendency or a decreasing tendency than the power measured. An IM unbalance compensation calculation section (306) generates unbalance IM characteristic so that an amplitude component and a phase component are different when the power is identical in the increasing tendency and the decreasing tendency of the power and generates a compensation signal of compensation characteristic having the amplitude component and the phase component symmetric to the unbalance IM characteristic generated for fixed values of the amplitude component and the phase component when an amplifier (312) is assumed to have a linear characteristic. A complex multiplier (308) combines the base band signal and the compensation signal. An amplifier (312) amplifies the base band signal and the distortion component generated when amplified is suppressed by the compensation signal. Thus, it is possible to accurately suppress the distortion component of the lower/upper unbalance.