Complexity-reduced Volterra series model for power amplifier digital predistortion

Abstract

This paper expounds a complexity-reduced Volterra series model for radio frequency power amplifier (PA) behavioral modeling and digital predistortion (DPD). An analysis was conducted, which took into account the memory effect mechanisms of the PA. This led to a closed-form expression that relates the memoryless behavior of the PA to the finite impulse response feedback filter, which approximates the memory effects’ behavior. The analysis resulted in a complexity-reduced Volterra series model which allows for a substantial reduction in the requirements for digital signal processors and the time needed to construct and implement the DPD in a real-time environment. The proposed model was validated as a behavioral model and a DPD using two different PA architectures, employing two different transistor technologies, driven by both 20 MHz 1001 wideband code division multiple access and long term evolution signals. The results obtained demonstrate the excellent modeling and linearization capability of the complexity-reduced Volterra series model.