Patent ID: 8605819

Claim:
A memory effect canceller comprising: a sample obtaining section that obtains a plurality of discrete-time samples of a transmission signal supplied to a power amplifier that amplifies a transmission signal; a signal generation section that generates a correction signal that is a weighted linear combination, using given weighting coefficients, of partial derivatives of a transfer function of the power amplifier, wherein the transfer function has been defined in advance with a plurality of discrete-time samples as input variables, and wherein the partial derivatives are based on the discrete-time samples obtained by the sample obtaining section at respective times; and a signal correction section that corrects an output signal of the power amplifier by adding the correction signal to the output signal of the power amplifier, wherein the signal generation section includes a plurality of first delay sections that delay the plurality of discrete-time samples in sequence, a subtracter that computes difference values between neighboring samples among the plurality of discrete-time samples, a plurality of second delay sections that delay the difference values computed by the subtracter in sequence, a plurality of computing sections that compute derivatives of the transfer function using samples at respective times based on the outputs of the first and second delay sections, a plurality of multipliers that multiply derivatives, computed by the computing sections, respectively by the given weighting coefficients, and an adder that adds the multiplication results obtained by the plurality of the multipliers.