Self-Powered Polarization-Reconfigurable Rectenna for Wireless Power Transfer System
Mingyang Chang, Jiaqi Han, Yicen Li, Xiangjin Ma, Haixia Liu, Long Li
Abstract
This article proposes a novel self-powered polarization-reconfigurable rectenna for wireless power transfer (WPT) systems. A three-state-reconfigurable network is designed, which is realized by two 3-dB bridges sharing a branch integrated with p-i-n diodes. The patch antenna can be excited to receive distinct polarized waves at 5.8 GHz by controlling p-i-n diodes’ ON or OFF state. In addition, a high-efficiency rectifier network includes two rectifier circuits integrating with a circulator for optimal input power. The function of the rectifier circuit 1 is to convert the radio frequency (RF) power in the power transfer link into direct current (dc) power. Rectifier circuit 2, as a part of the polarization control link, aims to use the energy reflected by the rectifier circuit 1 to provide a dc bias for the p-i-n diodes. A polarization-reconfigurable antenna without an external dc power source is realized. Finally, a WPT system is established based on the proposed self-powered polarized reconfigurable rectenna. The measured results show that the proposed rectenna has a maximum conversion efficiency of 66% at 5.8 GHz and a conversion efficiency higher than 50% in the incident power range from 21 to 30 dBm. It can flexibly adjust the polarization state without an extra dc power source, realizes efficient wireless power transmission, and can be widely used in WPT systems for different applications.