A GaN-Based Rectifier with Ultra-High Efficiency and Power Bandwidth

In this paper, a 2.4-GHz GaN rectifier with ultra-high efficiency and ultra-wide input power range is proposed for wireless power transmission. Firstly, an equivalent current model is proposed for accurately analyzing the power losses resulting from gallium nitride Schottky barrier (SBD) diodes. Based on the model, a custom GaN Schottky barrier diode is designed and manufactured. The series resistance and junction capacitance of the diode are decreased to 2.6 Ω and 0.47 pF, respectively, while the breakdown voltage is increased to 54 V. Then a wideband microwave rectifier is fabricated with harmonic harvesting and impedance compression technology. The test results shows that a maximum rectification efficiency of 90% at 25.2 dBm input power is achieved of the proposed rectifier. While the high-efficiency power range (efficiency ≥ 50%) is extended to 23.5dB (3.5-27dBm). The proposed GaN-based rectifier offers significant benefits for enhancing the working distance and anti-interference capabilities of wireless power transmission systems.