Performance of adaptive algorithms for compensation of radio over fiber links

Abstract

This paper considers the adaptive predistortion of the nonlinear distortions in a Radio over Fiber (RoF) link. In particular, we modify and compare two adaptive algorithms developed originally for the compensation of the linear systems, namely LMS and variable step size normalized LMS (VS NLMS). A recursive least squares (RLS) solution is used as a reference. Our simulation results indicate that over 40 dB improvement of adjacent channel power ratios can be achieved via the predistortion. Furthermore, we show that in the compensation of the nonlinear RoF link, the LMS can be used in such a way that its performance is comparable to more complex RLS.