Target driven design of electromagnetic metamaterial for dual-band Wi-Fi energy harvester

Abstract

With the development of Internet of things (IoT), there have a large amount of interconnected devices communicates with each other through electromagnetic (EM) waves sent by Wi-Fi router. It is promising to harvest Wi-Fi energy realizing wireless power transmission for sensors or microelectronic devices. However, the energy is hardly to be harvested effectively due to the complexity and disorder of EM waves. To address such issue, we propose an EM metamaterial based on parametric equation as dual-band Wi-Fi energy harvester operating at 2.45 GHz and 5.8 GHz. By adjusting these equation parameters, the prototype can achieve almost an arbitrary shape, avoiding the problem of local optimal solutions. Through the co-simulation of MATLAB and CST Studio Suite software, we design a genetic algorithm (GA) to optimize the proposed structure so that it can harvest energy at Wi-Fi frequency bands. The optimized metamaterial exhibits electric dipole resonance and magnetic dipole resonance simultaneously at 2.45 GHz and 5.8 GHz, and the maximum harvesting efficiency is 96.9% and 95% at normal incidence, respectively. In particular, the metamaterial has the characteristics of polarization insensitive, ultra-wide band and wide-angle harvesting. It is expected to integrate with small electronic devices to realize the function of remote energy conversion, self-powered, and maintenance-free in the era of advanced wireless networks.