A New Digital Predistortion Algorithms Scheme of Feedback FIR Cross-Term Memory Polynomial Model for Short-Wave Power Amplifier

Due to the non-linear behavior, high fractional bandwidth, relatively poor circuit matching, large standing wave of output port, large fluctuation of power tube temperature of the short-wave power amplifier (PA), it is difficult to achieve the expected performance in HF (High Frequency) communication to maintain high efficiency and improve the linearity of HF power amplifier at the same time. However, there are no optimization measures for the above problems in the traditional digital pre-distortion (DPD) model, which is always recognized as an effective technique to improve system linearity and efficiency. In this paper, the new Feedback FIR Cross-term Memory Polynomial Model (MPM) to compensate the characteristics of the short-wave PA is presented. The experimental results show that, comparing with the traditional MPM DPD look-up table (LUT) method and the Generalized Memory Polynomial Model (GMPM) LUT method, this model can improve IM3 of Adjacent Channels Power Ratio (ACPR) about 10 dB.