Patent ID: 6108385
Filing Date: 2000-08-22
Classification: H03F,H04L

Abstract:
In a communications system including,a modulator for modulating a plurality of information signals to provide a broadband input signal, V.sub.i, having a plurality of frequency terms,a broadband processor for combining said input signal V.sub.i and a predistortion signal V.sub.pd to form a predistorted input signal V.sub.id,a non-linear element having a non-linear transfer function for processing the predistortion signal, V.sub.id, to provide an output signal, V.sub.o, where the output signal includes terms of the Taylor series form [k.sub.1 (V.sub.i).sup.1, k.sub.2 (V.sub.i).sup.2, k.sub.3 (V.sub.i).sup.3, . . . ],a predistortion processor comprising,term generator means for generating selected predistortion terms of the Taylor series form [k.sub.1 (V.sub.i).sup.1, k.sub.2 (V.sub.i).sup.2, k.sub.3 (V.sub.i).sup.3, . . . ],phase shifter means for providing phase shifts to the selected predistortion terms to provide phase shifted terms that will reduce corresponding ones of the said terms in the output signal, V.sub.o,periodic signal generator means for generating periodic signals from said phase shifted terms,scaling means for scaling the periodic signals in proportion to the transfer function of the non-linear element to form said predistortion signal V.sub.pd.