High Efficiency 2.45 GHz Low Power Hybrid Junction Rectifier for RF Energy Harvesting

This paper presents a 2.45 GHz low power rectifier utilizing a 180° hybrid junction for radio frequency (RF) energy harvesting. This rectifier provides enhanced efficiency at low input power levels compared to the typical Greinacher voltage doubler rectifier. The proposed rectifier consists - in addition to the 180° hybrid combiner - of two rectifying branches and two output ports. Each rectifying branch is based on the Greinacher voltage doubler configuration but contains only one rectifying diode for each branch. Using of only one diode instead of two provides significant improvement in the efficiency of the RF rectifier. The proposed rectifier configuration has been simulated using advanced design system (ADS) and its performance has been investigated and compared to the ordinary voltage doubler rectifier. The proposed rectifier provides maximum power conversion efficiency (PCE) of 70 % compared to maximum PCE of 51 % for the ordinary voltage doubler circuit. Moreover, the proposed rectifier topology provides sensible enhancement of the efficiency at the lower input power levels.