Proposal of an EM Energy Harvesting Solution from Ambient Railway Communication Systems Based on Focusing Metasurfaces

In this paper, we investigate the potential of an EM energy harvesting system based on focusing metasurfaces to enhance the performance of off the shelf rectenna systems, and overcome the challenges of low efficient ambient EM energy harvesting from railway communication systems. The metasurface is designed based on the hyperboloidal profile of the generalized phase law. Our energy harvesting system is deployed in the railway environment in three configurations: The receiving antenna of the rectenna along side the focusing metasurface, the antenna along side a metallic plate and the antenna alone. The focusing concept shows remarkable results compared to the other configurations with a receiving power up to 10 µW compared to that of the antenna with a metal plate and alone of 1 µW and 0.1µW respectively, which can be an interesting result to supply low input WSNs where such power in needed to wake up the device.