Patent ID: 8421534
Filing Date: 2013-04-16
Classification: H03F

Abstract:
1. A predistorter comprising: a predistortion filter predistorting an input signal u(n) by using a filter modeled by using the input signal u(n) and a past value of the input signal u(n) to provide an output signal x(n); a predistortion output estimation unit estimating the characteristics of a nonlinear device based on a signal y(n), processed by the nonlinear device and the output signal x(n), and calculating a desired output signal z(n) of the predistortion filter by using the estimated characteristics of the nonlinear device; and an adaptive algorithm driving unit comparing the output signal x(n) with the desired output signal z(n) to output an error as a comparison result, calculating a filter coefficient according to which the calculated error is minimized, and providing the calculated filter coefficient to the predistortion filter in order to update a filter coefficient of the predistortion filter.