Distortion-compensated amplifier device

Abstract

Excellent compensation of the distortion is realized with a distortion-compensated amplifier device that compensates a distortion that is generated in a main amplifier, through the respective operations of a circuit comprised of a distortion-detecting loop and a distortion-compensating loop and a pre-distortor. In a distortion-detecting loop, the signal is distributed. With respect to one distribution signal, a vector adjuster ( ) performs vector adjustment of it and the pre-distortor ( ) generates a distortion. A main amplifier ( ) amplifies this signal. The resulting amplification signal and the other distribution are composed, whereby a distortion component is detected. In a distortion-compensating loop, that amplification signal and this distortion component are composed to thereby eliminate the distortion component from the amplification signal. In a control part, a distortion component level detecting means ( ) detects the levels of the distortion component that is detected. Vector adjusting/controlling means ( ) and ( ) controls the vector adjusting means ( ) to thereby make the average value of those levels small. On the other hand, pre-distortor controlling means ( ) and ( ) controls the pre-distortor ( ) to thereby make the peak values of those levels.