A Dual-Band, Polarization-Insensitive, Flexible Rectifying Metasurface for RF Energy Harvesting

In this paper, a dual-band, polarization-insensitive and flexible rectifying metasurface (RMS) is proposed for radio frequency (RF) energy harvesting. The RMS system is matching-free due to its Schottky-diode loaded unit cells. By introducing the gaps between parallel metasurface resonator, not only can dual-band feature be obtained, but direct impedance matching between diodes and metasurface can also be achieved. The simulated results show that the proposed RMS unit can maintain high harvesting efficiency with arbitrary polarization angles. Furthermore, a 3×3 array is designed and analyzed. The simulated results show that the proposed RMS system can achieve maximum efficiency of 75% at 2.4GHz and 76% at 5.8GHz. Moreover, the array performs well under different curvature cases, which indicates its potential for wireless power supply of wearable devices.