Rectifying Surface Implemented with a Coupled Array

Abstract

A left-hand circularly polarized microwave rectifying surface consisting of 8×8 sub-wavelength resonant elements and the same number of rectifying circuits is designed, implemented and measured. Working at 5.8 GHz, this rectifying surface was tuned to obtain an optimal impedance matching to the air, a complex-conjugate impedance matching to the rectifying circuits, and a strong impedance mismatching to the air at harmonic frequencies, simultaneously. The measured RF-to-DC conversion efficiency reaches up to 67.35% under an incident power density of 7.45 mW/cm2.