Linearization Angle Widened Predistortion for Hybrid Beamforming Array Utilizing Iterative Post-Weighting

While beam-oriented digital predistortion (BO-DPD) is an effective technique to deal with power amplifier (PA) nonlinearity in hybrid beamforming (HBF) communication systems, it suffers from a limited linearization angle. Recent research shows such a drawback can be substantially mitigated by a post-weighting (PW) process. However, the linearization performance of traditional PW-DPD still has room for improvement since the PA distortion is therein approximated by a constant term irrelevant to the PW coefficients. In this work, we address the linearization angle widening issue via an iterative approach based on the alternating optimization framework, which leads to better performance in distortion reduction compared to the conventional PW scheme.