Three-Layered Biased Memory Polynomial for Dynamic Modeling and Predistortion of Transmitters With Memory

This paper proposes a new three-layered biased memory polynomial for behavioral modeling and digital predistortion of highly nonlinear transmitters/power amplifiers (PAs) for 3G wireless applications. The proposed model considers the possibility that the nonlinearity order of the dynamic part of the PA characteristics is different from the nonlinearity order of the static part. For highly nonlinear PAs, the proposed model offers some benefits, such as a low dispersion of coefficients, numerical stability and a low number of coefficients. Moreover, with the measurement setup, better in-band performance is reported. To establish the performance of the linearized PA under realistic conditions, experiments have been carried out for a deep biased class-AB PA and a Doherty PA for various modeling and signal quality norms defined for 3G signals.