Patent ID: 6809607
Filing Date: 2004-10-26
Classification: H03C,H03D,H04L

Abstract:
A method for compensating for non-linear distortion generated during non-linear high-power amplification in a transmitter for quadrature-modulating a baseband signal, non-linearly high-power amplifying the quadrature-modulated baseband signal, extracting a non-linear distortion component from the non-linearly high-power amplified modulated signal, quadrature demodulating the extracted distortion component into a baseband distortion component, and overlapping a phase-inversed distortion component of the quadrature-demodulated baseband distortion component with the baseband signal, comprising the steps of:variably shifting a phase of a signal determined by quadrature modulating the baseband signal; non-linearly high-power amplifying the quadrature-modulated signal by a high-power amplifier; variably attenuating the amplified signal by a gain equal to that of the high-power amplifier; extracting non-linear distortion generated during the non-linear high-power amplification by subtracting the phase-shifted quadrature-modulated signal from the attenuated signal; and automatically adjusting a phase delay of the phase-shifted signal and an attenuation of the attenuated signal according to a transmission frequency.