Low-Rate Digital Predistortion for Broadband Power Amplifiers Using Bidirectional Model

DOI number:10.1109/LMWT.2025.3592118

Affiliation of Author(s):国防科技大学电子对抗学院，中国科学技术大学信息学院

Journal:IEEE Microwave and Wireless Technology Letters (Online)

Funded by:NSFC 62371436, 62171450, 62201602

Key Words:Broadband transmission, digital predistortion (DPD), power amplifiers (PAs), sampling rate reduction.

Abstract:Low-rate digital predistortion (DPD) significantly reduces running power consumption and deployment cost, but the aliasing effect degrades the linearization performance for power amplifiers (PAs). In this letter, we propose a novel bidirectional DPD model that augments the baseline model with a few noncausal terms to reduce the aliasing effect caused by baseband rate reduction. The proposed model is derived from band-limited (BL) DPD but avoids the high-rate filtering of the basis functions through implicit filtering. To validate the proposed model, we conducted experiments on a GaN-based Doherty PA driven by 100/200 -MHz modulated signals. Experimental results show that the proposed model achieves satisfactory linearization performance with a sampling rate of 1.5× signal bandwidth. In addition, the proposed method significantly reduces the number of coefficients compared with the state-of-the-art method.

First Author:Chengye Jiang

Co-author:Junning Zhang

Indexed by:Journal paper

Correspondence Author:Falin Liu,Bo Tang

Document Code:10.1109/LMWT.2025.3592118

Discipline:Engineering

Document Type:J

Volume:Online

Issue:Online

Page Number:1-4

Translation or Not:no

Date of Publication:2025-07-31