Linearization Angle Widened Digital Predistortion for 5G MIMO Beamforming Transmitters

To reduce the demand for frequently adjusting phase shifts in fifth-generation (5G) multiple-input multiple-output (MIMO) beamforming transmitters, this article, a novel digital predistortion (DPD) technique is proposed, which employs multiple boxes to shape pattern of nonlinear distortions space order linearize targets simultaneously. By using approach, linearization angle widened and thus communication quality can be kept when user moves off main beam direction. As proof concept, two DPD boxes, namely auxiliary are used realize 2-target linearization. A new model extraction method also proposed with dedicated over-the-air (OTA) feedback post-processing stage. Simulation experiment demonstrated on 4-path transmitter. The results show that effectively widen reasonable additional complexity.