An adaptive algorithm for digital predistortion01An adaptive algorithm for digital predistortion Shanying Wu, S.F.Simon Hau, Yi Zhao Department of Electronic & Information Engineering, the Hong Kong Polytechnic University Kowloon, Hong Kong, China enwsyky(polyu.edu.hk ABSTRACT This article presents an adaptive digital predistortion (DPD) for linearizing RF power amplifiers (PA). The idea is to use nonlinear curve-fitting in conjunction with the look-up table to adaptively pre-adjust the gain and the phase of the input data before it is fed to the amplifier. The performance of the algorithm is tested by simulation. The input data is that of the standard IS-95A test signal and the data used to simulate the nonlinear characteristics of the device is measured from a 30 watt commercial CDMA PA operating at 50 watt. The results showed that ba……