A NEW ACCURATE VOLTERRA-BASED MODEL FOR BEHAVIORAL MODELING AND DIGITAL PREDISTORTION OF RF POWER AMPLIFIERS

Abstract

A new accurate Volterra-based model is introduced for behavioral modeling and digital predistortion (DPD) of power ampliflers (PAs). This model extends the GMP model with speciflc cross terms, and these augmented terms signiflcantly increase the model's performance. The proposed model's performance is assessed using a LDMOS Doherty PA driven by two modulated signals (a 4-carrier WCDMA signal and a single carrier 16QAM signal). The experimental results in both behavioral modeling and DPD applications demonstrate that the proposed model outperforms the hybrid memory polynomial-envelope memory polynomial (HME) model and generalized memory polynomial (GMP) model. Compared with the HME model, the proposed model shows an average normalized mean square error (NMSE) improvement of 2.2dB in the behavioral modeling, average adjacent channel power ratio (ACPR) improvement of 2.8/2.5dB in the DPD application, and 20% reduction in the number of coe-cients. In comparison with the GMP model, the proposed model achieves higher model accuracy and better DPD performance, but reduces approximately 40% of coe-cients.