Patent ID: 6385436
Filing Date: 2002-05-07
Classification: H03F,H04B

Abstract:
A distortion compensation circuit comprising:a vector adjuster for electrically adjusting amplitude and phase characteristics of an input signal; a linearizer, constructed of analog linear and nonlinear elements and having amplitude and phase characteristics opposite to those of an amplifier with respect to changes in input power, which is an output of said vector adjuster, for electrically adjusting the amplitude and phase characteristics with respect to the changes in input power, said amplifier being connected to the succeeding stage of said linearizer; a linear signal extraction path for extracting part of the input signal from the input side of said vector adjuster; a nonlinear signal extraction path for extracting part of an output signal from the output side of said amplifier; a level detector for detecting a combined power level of the signals from said linear signal extraction path and said nonlinear signal extraction path; and a control circuit for adjusting a bias of said linearizer in accordance with the detected combined power level, electrically adjusting said linearizer so that the power detected by said level detector is minimized, and adjusting said vector adjuster so that the power detected by said level detector is minimized every time said linearizer is adjusted.