A 2.45- and 5.8-GHz Dual-Band Stacked Differential Rectenna With High Conversion Efficiency in Low Power Density Environment

This paper proposes a novel stacked dual-band differential rectenna. The proposed rectenna consists of two rectifying diodes and a dual-band array antenna with four 5.8-GHz patch antennas arrayed on a three-element 2.45-GHz array. The dual-band array antenna provides high gains of 12.2 and 13.8 dBi at 2.45 and 5.8 GHz, respectively. The matching circuits between the antenna elements and diodes are designed to provide the highest conversion efficiency at both 2.45- and 5.8-GHz band. The measured conversion efficiencies are 36.4% and 6.2% at 2.48 and 5.96 GHz under the low power density condition of 0.016 W/m
²
, respectively. The proposed dual-band differential rectenna can easily realize large-scale rectenna arrays by simply connecting the ground conductors on the back.