Design of a Self-Driving Transistor-Based RF-DC Converter Based on Optimized Harmonic-Tuned Rectification Waveforms

Abstract

In order to apply the traditional power amplifier’s (PA) waveform engineering in an RF-dc rectifier design, a piecewise ON-resistance transistor model is introduced into the derived equations. In this proposed analysis method, the connection between the drain voltage and current is built in order to make the theoretical waveforms easily applied to a practical rectifier design with optimized parameters of the best efficiency. Continuous class-F/inverse class-F and continuous class-B/J waveforms are evaluated with numerical examples in this work. Thus, the rectification performance with different classes and parameters can be compared. This study shows that a continuous class-F and a continuous class-B/J rectifier can barely offer higher than 52% and 70% efficiencies with precise on-duty ratio ( $D$ ) of 0.5, respectively, except by reducing the conduction angle. However, a continuous inverse class-F shows the best rectification efficiency (easily higher than 85%) among all the studied cases for $D=0.5$ . A self-driving inverse class-F design example with optimized parameters is given to verify the theoretical analysis and demonstrate the high-efficiency performance. The rectification efficiencies of 74.9% and 80.7% are measured for 11.2- and 6 W-input powers at 1.9 GHz, respectively.