A new predistorter based on memory polynomials and LUT

Digital base band predistortion is a highly cost-effective way to linearize PAs, but the existing architectures assume that the PA has a memory less nonlinearity. For wideband application, such as DVB-T (digital video broadcasting-terrestrial) system, PA memory effects can no longer be ignored. The predistorter based on look-up table (LUT) cannot compensate the distortion caused by memory effects. The predistorter based on memory polynomials (MPM) is an effective approach for the linearization of PAs with memory effects. But when the nonlinearly of PAs becomes stronger, the performance of MPM becomes worse. In this paper, we give the simulation results of the predistortion based on MPM with DVB-T signal, and analyze the drawback of the approach. At the end of the paper, we proposed a new predistorter based on both memory polynomial and LUT. It is implemented using an indirect learning architecture.