A Digital Pre-Distortion Based on Nonlinear Autoregressive With Exogenous Inputs

In this letter, a new pre-distortion technique for power amplifiers in wideband applications is proposed. The proposed pre-distortion technique is based on Nonlinear Autoregressive with Exogenous inputs (NARX). The forward path of the proposed predictive method is based on the memory polynomial. Experimental validation is carried out with 4 carrier WCDMA signal with 20MHz bandwidth and PAPR = 9.8 dB. The results show significant reduction in the number of coefficients with comparable performance in terms of adjacent channel leakage ratio (ACLR) and error vector magnitude (EVM) to Volterra series techniques.