High Power Microwave Rectifier for Lower Variation to Input Power and Phase

This work presents a novel high efficiency and low complexity radio frequency (RF) to direct current (DC) rectifier was designed for wireless power transfer (WPT) applications at 2.45 GHz. The proposed circuit is based on a Branch line coupler (BLC) and shunt diode rectifier that maintains high conversion efficiency over a broad range of input power. The circuit has been simulated and optimized with help of Advanced design system (ADS) using a Large signal S-parameter (LSSP) tool on RT/duroid 5880 substrates with h = 0.8 mm and ϵ
r
= 2.2. The reflection coefficient remains less than −15 dB for the complete simulation power range (0 to 36 dBm). The peak power conversion ratio obtained for the designed circuit is 67.19% for input in-phase power equal to 32 dBm. With variation in relative input phase (at the second coupler port) between 0° to 360°, the efficiency remains higher than 50% from 23 to 34 dBm.