Physically-Derived 3-Box Power Amplifier Model

In this work, a novel approach to reduce the complexity of memory polynomial model is presented. The proposed technique, named the coefficient decomposition (CD) technique, is based on reducing the search space for the memory polynomial coefficients based on memory effects generation mechanism. In this paper, the technique is demonstrated for power amplifier of classes A and AB. In this case, the physical analysis shows that the conventional two-dimensional coefficient architecture of the memory polynomial could be simplified into a one dimensional architecture while keeping almost the same accuracy. The performance of the proposed approach is demonstrated and compared with other models using a 30 dBm commercial power amplifier with 20 MHz and 60 MHz LTE signals. The measurements and simulations showed that, the presented model achieves -34.2 dB of NMSE while needing only 13 coefficients compared with 25 needed for a memory polynomial model. Also, the DPD performance of the proposed model is the same as memory polynomial model and comparable with high complexity models like the PLUME and GMP.