Design and experiment of RF rectifiers for wireless power transmission

This paper presents the design and experiment of series mounted diode rectifier and single stage voltage doubler rectifier at 2.45GHz for applications involving microwave power transmission. Input matching circuit and harmonics filtering at both the input and output have been optimized for high efficiency operation. The series topology is dedicated to low input power conversion. Measurement results show that 40% and 27% RF-DC conversion efficiency are achieved for 0 dBm and -5 dBm input power respectively at 2.45GHz. A maximum efficiency of 54% is obtained for an input power of 12 dBm and a 3V output DC voltage is measured at a 1KΩ DC load when the rectifier is matched to 50Ω. The voltage doubler structure is aimed for high input power conversion and exhibits more than 4V at 2.4GHz for input power above 15 dBm.