Digital predistortion apparatus and method in power amplifier

摘要

A digital predistortion apparatus is provided for predistorting a nonlinear characteristic caused by a wideband power amplifier that amplifies a input signal. The digital predistortion apparatus includes a predistorter, connected to the power amplifier via a digital-to-analog converter (DAC) and a frequency up-converter, for receiving the input signal and compensating for the nonlinear characteristic using a look-up table that depends upon a change in output power of the power amplifier. The digital predistortion apparatus further includes look-up table (LUT) updating block for adaptively updating the look-up table by comparing a feedback signal output from the power amplifier, connected thereto via an analog-to-digital converter (ADC), with the input signal output from the predistorter.