A Dual-Band Simple Coplanar-Structured Rectifying Metasurface for Wireless Energy Harvesting

A dual-band and coplanar-structured rectifying metasurface (RMS) is proposed in this letter. The ultra-compact RMS consists of tightly coupled positive (+) and negative (−) metallic resonant patches with coplanar-welded diodes. Two absorptive modes are excited to achieve high MS impedance at dual resonances, so that the proposed MS can directly match with the high-impedance rectifying circuits, eliminating additional impedance matching and power combining networks in conventional works. Moreover, the incident waves under different polarizations and oblique incident angles can be effectively captured. The results show that the peak simulated efficiency is 63.7% (measured 54.3%) at 2.45 GHz and 61.5% (measured 52.7%) at 5.8 GHz with the input power of 0 dBm. This design strategy based on intrinsic resonance, are insensitive to the array-number, equipped with the advantages of simple construction, low incident power, multimode resonance and polarization insensitivity, which shows great potential in complex applications of energy harvesting.