A Dual-Polarized, Notched Electromagnetic Energy Harvester Array Based on FSS

In this letter, a dual-polarized, notched ambient electromagnetic (EM) energy harvester array based on frequency selective surface (FSS) is presented. The proposed unit structure consists of a notched solid patch with two through-vias. By introducing the notches into the solid patch, the current aggregation at the through-vias is enhanced. As a result, the EM energy flow is constrained and high harvesting efficiency is achieved. Then, a 9×9 harvester array was fabricated and measured. Simulated and experimental results demonstrate that the proposed harvester features dual-polarization and wide-angle insensitive characteristics. At a 60° incidence angle of both TE and TM polarization, the harvesting efficiency exceeds 78%. Also, the half power bandwidth maintains above 100MHz, which covers the WIFI band. Besides, it is also shown that the notched harvester has a small operating frequency offset of 30MHz (1.23%). The proposed harvester can be used to construct a high-efficiency EM energy harvesting system for the wireless power supply of IoT sensors.