A Custom C Band High-Power GaN-Based Rectifier for WPT Systems

This study presents the development of a 5.8 GHz high-power voltage doubling rectifier for wireless power transfer (WPT) applications, leveraging advanced gallium nitride (GaN) Schottky barrier diode (SBD). The GaN SBD, designed for high-frequency and high-power operation, features a wide bandgap, high electron mobility, and high saturation velocity, ensuring superior performance in microwave power rectification. Key characteristics include a high breakdown voltage larger than 200 V, a low zero-bias junction capacitance of 0.34 pF, a turn-on voltage of 1.25 V, and an on-resistance of 10.5 Ω. These properties enable efficient rectification at the C band. The GaN SBD is integrated into an optimized rectifier circuit featuring a harmonic compression structure to enhance performance, a peak RF-to-DC conversion efficiency of 77.4% is achieved at an input power of 39 dBm. These results highlight the potential of high-power GaN SBDs in advancing high-frequency, high-power WPT systems.