Wideband metamaterial absorber based on CRRs with lumped elements for microwave energy harvesting

A novel metamaterial absorber structure is designed and characterized for microwave energy harvesting. The suggested structure is composed of two circular ring resonators with different dimensions. Due to harvesting application of the proposed structure, the main operation frequency of the suggested structure lies in WIMAX and satellite communication frequency bands and surrounds our environment. The optimum dimensions of the suggested structure are obtained through parametric study by genetic algorithm in order to realize wideband absorption and harvesting response. Simulation results show that the metamaterial-harvester-based resistive loads are useful to absorb and convert microwave energy for the operation frequency. The simulated harvested power across the resistors has been found greater than 0.4 W, which corresponds to 80% efficiency between 7.8 and 14 GHz. In addition, polarization dependence and angular stability of the proposed harvester are investigated at operation frequency to support the simulation of an experimental study for S-parameter measurement. Therefore, simulation and experimental study results show that the proposed design with good absorption and harvesting characteristics can be operated in WIMAX and satellite communication frequency bands.