Orthogonal polynomial-based digital predistortion for wideband power amplifiers

A novel orthogonal polynomial-based modeling and digital predistortion technique for wideband power amplifiers is presented in this paper. The conditional number of the matrix affects the stability of LMS algorithm. Orthogonal polynomial is therefore employed for memory power amplifier with high order. The LMS and RLS combined algorithm is used to estimate coefficients of the digital predistorter. Simulation results show that, than compared to digital predistorter using conventional polynomials, the proposed orthogonal polynomial-based digital predistortion technique achieves better performance in nonlinear and memorial distortions for wideband power amplifiers.