This paper proposes a class-F synchronous rectifier using an independent second harmonic tuning circuit for the power receiver of 2.4 GHz wireless power transmission systems. The synchronous rectifier can be designed by inverting the RF output port to the RF input port of the pre-designed class-F power amplifier based on time reversal duality. The design of the class-F power amplifier deploys an independent second harmonic tuning circuit in the matching networks to individually optimize the impedances of the fundamental and the second harmonic. The synchronous rectifier at the 2.4 GHz frequency is designed and implemented using a 6 W gallium nitride high electron mobility transistor (GaN HEMT). Peak RF-dc conversion efficiency of the rectifier of 69.6% is achieved with a dc output power of about 7.8 W, while the peak drain efficiency of the class-F power amplifier is 72.8%.

中文翻译：

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使用独立的第二谐波调谐电路的.4 GHz GaN HEMT F类同步整流器

本文提出了一种采用独立的二次谐波调谐电路的F类同步整流器，用于2.4 GHz无线电力传输系统的电力接收器。可以通过基于时间反转对偶性将RF输出端口转换为预先设计的F类功率放大器的RF输入端口来设计同步整流器。F类功率放大器的设计在匹配网络中部署了独立的二次谐波调谐电路，以分别优化基波和二次谐波的阻抗。使用6 W氮化镓高电子迁移率晶体管（GaN HEMT）设计和实现2.4 GHz频率的同步整流器。直流输出功率约为7.8 W时，整流器的峰值RF-dc转换效率达到69.6％，