Design of a Compact Line-of-Sight Rectenna for Wireless Power Transfer Systems

This paper presents the design of a compact line-of-sight rectenna system for wireless power transfer and energy harvesting applications. The proposed rectenna consists of a highly-directive Vivaldi microstrip antenna and a voltage doubler rectifier circuit assembled in the same double-sided copper fiberglass substrate. To achieve the established requirements for the antenna, a mixed optimization process is proposed by using alternately two techniques: Particle Swarm and Covariance Matrix Adaptation Evolution Strategy. In addition, to limit the rectifier output current, a buffer circuit is proposed to interface the rectifier output and the load. Finally, the proposed methodology and the designed rectenna are numerically and experimentally characterized, and the obtained results confirm the system’s capacity to power low-consumption loads.