2016 Volume 13 Issue 2 Pages 20150998
A digital predistortion (DPD) technique to linearize multiple power amplifiers (PAs) in analog beamforming systems is proposed. The analog beamforming system considered in this paper has one digital chain and multiple PAs/antennas controlled by phase shifters. Due to the system configuration, a single DPD should linearize the multiple PAs. To design the DPD, this paper introduces a cost function, squares of the sum of errors for all the PAs. The DPD solution minimizing the cost function is found by a recursive least squares (RLS) algorithm. Experimental results with commercial PAs show that the proposed DPD can effectively linearize multiple PAs.