Dynamic Matching Power Amplification Technique for Transmitting Time-Varied Signals With Large Modulated Bandwidth and Frequency Range

Abstract

This article proposes a novel high-efficiency high-linearity dynamic matching power amplification technique for transmitting time-varied signals with large modulated bandwidth and frequency range in 6G flexible spectrum scenarios. This technique integrates the signal preprocessing technique in the digital domain with injection-control matching power amplifier (PA) in the analog domain. By employing a digital filter, control signals with a relatively low power are injected into the PA’s output for dynamic impedance matching within a large modulated bandwidth. Moreover, by updating the coefficients of the filter, the control signals are dynamically generated in response to carrier frequency and modulated bandwidth changes. Incorporating dynamic digital predistortion (DPD) at the input helps to realize the linearization of the proposed structure, leading to a system that consistently maintains both high efficiency and linearity. The measurement results show that the proposed architecture achieved the average power added efficiency (PAE) of 35.7%–41.1% while transmitting 200-MHz 5G-NR signals within the 1–3.8-GHz range. The normalized mean square error (NMSE) of around -35 dB and the adjacent channel leakage ratio (ACLR) of around -45 dBc were achieved under different modulated bandwidths and operating frequencies.