High-Efficiency High-Linearity Power Amplification Technique by Digital-Assisted Injection-Control Matching for 6G Flexible Spectrum Applications

This article proposes a novel high-efficiency high-linearity power amplification technique for 6G flexible spectrum application. It combines digital-assisted dynamic signal preprocessing technique with analog injection-control matching power amplifier (PA) technique. The control signal injects into the output end to achieve reconfigurable load varied with scenario, and its power levels are relatively low by implementing a novel design method of fixed output prematching network. The dynamic digital predistortion (DPD) signal injects into the input end to realize the linearization of the proposed structure to meet the requirement of the flexible spectrum. Measurement results show that the proposed architecture achieved peak power-added efficiency (PAE) of 56.6%-74% and 6-dB power back-off with normalized mean square error (NMSE) around $-$ 40 dB and adjacent channel leakage ratio around $-$ 50 dBc after linearization during 0.8-4 GHz. Besides, the compatibility for multimode multiband scenarios is also validated by employing 2G-GSM/3G-WCDMA/4G-LTE/5G-NR signals, and satisfactory performance is obtained.