Improved circularly polarized rectenna design for microwave power transmission at 2.45GHz

Interest for Wireless Power Transmission systems (WPTs) is increasing since they allow for power supplied devices involving low power consumption, located in unreachable area or needing expensive maintenance costs. In this paper we will present a rectenna design which is modeled and evaluated for an WPTs at 2.45GHz. The proposed rectenna structure consists of a 3×3 receiving antenna array with circular polarization which provides a high gain of 9.25dBi, and a microstrip RF-to-DC rectifier based on a voltage doubler circuit with HSMS 2820 Schottky diode, which provides a high conversion efficiency of 78% and a DC output voltage of 13.6V can be reached for a given input power level of 24dBm and an optimum load of 950Ω.