An Efficient Mulitfeed Rectenna For RF Energy Harvesting

This paper presents a multifeed rectenna for high-efficiency RF energy harvesting. By using a multifeed slot loop antenna and co-designing the antenna and the rectifier circuit, the lossy impedance matching network between the antenna and the rectifier is eliminated to boost the RF-to-DC conversion efficiency. Additionally, using multiple antenna feeds extends the high-efficiency region of the rectifier, which in turn, allows for high DC output power and high efficiency simultaneously. A proof-of-concept two-feed rectenna is designed and tested at 960 MHz. It achieves a peak efficiency of 64.5% and a combined DC output voltage of 1.72 V at an input power density of
$\mathbf{2.3} \mu \mathbf{W}/\mathbf{cm}^{2}$
, demonstrating state-of-the-art RF energy harvesting performance.