Patent Document ID: 20030108120
Application ID: 10307433
Patent Flag: 0

Claim One:
1. A predistortion amplifier comprising: a 2-variable polynomial calculating unit for calculating a polynomial using real and imaginary parts of a baseband complex input signal as its two variables and having a complex coefficient; an orthogonal modulator for performing orthogonal modulation using two carriers perpendicular to the real and imaginary parts of an output signal of the polynomial calculating unit; a distributor for distributing the output of the orthogonal modulator to a power amplifier for power amplification and to part of an output of the power amplifier; an orthogonal demodulator for performing orthogonal demodulation over an output signal of the distributor and generating a baseband complex demodulation signal; and a coefficient updating section for sequentially updating a complex coefficient of the polynomial calculating unit on the basis of said baseband complex input signal and said baseband complex demodulation signal.