Improving Power Amplifier Efficiency and Linearity Using a Dynamically Controlled Tunable Matching Network

摘要

This paper presents a tunable matching network that enhances both efficiency and linearity of power amplifiers (PAs). A medium-power amplifier with a varactor-based matching network is designed, fabricated, and tested. It is demonstrated that not only the power efficiency at reduced drive levels can be improved but also the AM–AM and AM–PM distortions of the PA are reduced when the tunable matching network is biased according to the input drive level. Moreover, under 3GPP WCDMA modulated input, the PA with a dynamically controlled tunable matching network achieves up to 5% improvement in drain efficiency when compared with a PA employing a fixed matching network.