Patent ID: 7418058

Claim:
A distortion compensating apparatus which compensates for nonlinearity of an amplifier by adaptively updating a distortion compensation coefficient for an input signal input to the amplifier based on a difference between an input signal and an output signal of the amplifier, said apparatus comprising: distortion amount detecting means which detects the amount of distortion of an output signal of the amplifier; parameter holding means which holds a parameter having been set therein, said parameter holding means being capable of varying the difference according to the parameter set therein; parameter correcting means which corrects the parameter held in said parameter holding means in such a manner that the distortion amount detected by said distortion amount detecting means is improved; control means performing control such that a frequency component that is to be subjected to distortion amount detection to be performed by said distortion amount detecting means is selected from a plurality of different frequency components, based on results obtained by weighing a plurality of the distortion amounts of the plurality of different frequency components of the output signal of said amplifier in accordance with specification values relating to the distortion amounts.