Switched mode power amplifier linearization using digital predistortion

Abstract

This paper proposes the realization of a three box parallel nonlinear model for predistorting a switched mode power amplifier (PA). Such amplifiers are highly efficient but exhibit very strong nonlinear effects, and this constraint has considerably limited their use. Through the implementation of accurate models as the predistorter, the nonlinearity inherent in the switched mode power amplifier can be compensated for. Driven by a wideband signal, simulations show that the model used achieves an improvement of 1.224dB in the adjacent channel power ratio (ACPR). Overall, the PA maintains 71.3% power added efficiency (PAE), a significant increase over other classes.