A piecewise generalized memory polynomial model for envelope tracking power amplifiers

This paper proposes a novel piecewise generalized memory polynomial model for envelope tracking power amplifiers (ETPAs). First, the input complex envelope signal is decomposed into several sub-signals by employing vector threshold decomposition technique and each sub-signal is processed separately by using generalized memory polynomial(GMP) model. Then, the selection of thresholds is discussed in detail to achieve optimum modeling accuracy. Simulation results show that the proposed model can provide about 3dB improvement of NMSE compared to the traditional memory polynomial(MP) model with same number of model coefficients, and can accurately describe the distinct characteristics of the ET system.