A 5.8-GHz GaN-Based Rectifier with High Power and High Efficiency

In this paper, a high-power rectifier based on gallium nitride (GaN) Schottky barrier diode is proposed for wireless power transmission (WPT) at 5.8 GHz. Firstly, a tri-bridge structured patterned Schottky diode is designed and fabricated. The small series resistance (1.3 $\Omega)$ and low turn-on voltage (0.49V) are advantageous for reducing power losses, while the high breakdown voltage (50 V) is designed to cope with high-power scenarios. Subsequently, a high-efficiency and wide-band single-series rectifier operating at 5.8 GHz is proposed. The load resistance is intentionally optimized to 100 $\Omega$ to enhance the current driving capability of the rectifier. Measurements show that a maximum conversion efficiency of 72.4% is achieved at an input power of 33.4dBm, resulting in a DC voltage of 12.59V (current of 125.9mA). The rectifier achieves an efficiency over 60% in the power range of 25dBm to 35dBm and indicates the potential to provide energy for high-power devices such as electric vehicles.