A Class-F High-Power Rectifier Circuit Based on Admittance Matching

This paper proposes a novel high-efficiency microwave rectifier circuit with a three-stage harmonic control network based on admittance matching technology. The microwave rectifier circuit is mainly composed of a three-stage Class-F harmonic control network, an admittance matching structure, and a DC filtering structure. The three-stage Class-F harmonic control network, featuring a simple structure, not only achieves the control of the second and third harmonics but also performs impedance control on the fourth harmonic to further improve efficiency, while also realizing the impedance matching function. The DC filtering structure eliminates traditional LC components to reduce losses; meanwhile, it uses fan-shaped microstrip lines to achieve filtering and completes admittance matching with the three-stage harmonic control network. This paper presents the simulation, fabrication and measurement of a high-power rectifier circuit. The results of the measurement show that at 2.55 GHz, with an input power of 32.5 dBm, the rectifier circuit achieves a maximum rectification efficiency of 76.9%, exhibiting excellent high-power performance. Additionally, it addresses the difficulty of impedance-matching technology being relatively complex for parallel circuits. The use of admittance for matching provides valuable reference significance for reducing the complexity of parallel circuit matching and enhancing the intuitiveness of matching in related research.