Low-profile broadband metamaterial-based RF energy harvesting with mushroom EBG structure

A novel Radio Frequency (RF) energy harvesting circuit is presented. The antenna comprises a low profile, 4 × 4 array of Electromagnetic Band Gap (EBG) unit cells that are fed through a centred slot in a ground plane. The antenna gain is over 6 dBi and its operational bandwidth covers a wide frequency band of 1.01 GHz from 5.03 GHz to 6.04 GHz. It is shown that the EBG unit cell demonstrates a band gap from 3.26 GHz to 6.45 GHz that can effectively inhibit surface wave propagation over the entire band of operation of the antenna. The antenna is integrated with a stacked Grenaicher rectifier circuit and demonstrates a simulated maximum efficiency of 50.4 percent and output voltage of 3.3 V for an input power of 3 dBm which is sufficient to power a wireless sensor node.