A 2.45 GHz FSS Loaded Rectifying Antenna

Abstract In this paper the development of a rectenna system has been presented for 2.45 GHz wireless power transfer application. The receiving element of the rectenna (or the antenna) has been designed to possess spurious free response at least up to 10 GHz to improve the RF-DC conversion efficiency. It was found that the gain of the antenna is not sufficient for rectenna application. Therefore, to improve the gain of the antenna, it has been loaded with an angle and polarization insensitive FSS. The FSS loaded antenna achieved 7.7 dB gain, 85% radiation efficiency, and single operating band at 2.45 GHz; which is suitable for developing a rectenna for wireless power transfer. To convert the received RF energy into DC voltage a 2.45 GHz matched rectifier circuit has been designed. L-type matching network has been used to match the complex rectifier impedance with the 50 Ω antenna impedance. 1.52 V output voltage was obtained for 7 dBm input power and 3 kΩ load. Achieved maximum efficiency is 66.13% for 1.1 mW received power. It has been shown that the FSS loading of the antenna has the capacity of drastically improve the efficiency of the rectenna system.