A compact-sized four-band metamaterial-based perfect absorber for electromagnetic energy harvesting applications

This study presents a novel, compact-sized four-band metamaterial absorber that can be used for ambient Energy Harvesting (EH). The absorber was analyzed both numerically and experimentally. The structure size is 10 x 10 x 1.575 mm3, and it is proposed to operate in S-band. The proposed design outperforms earlier designs, which have substantial drawbacks such as a bulky metamaterial structure, reduced absorption frequency ranges, and a lower absorption band fraction. High absorption coefficients and Polarization-insensitive behaviour across a large angle range are prominent features of the proposed four-band absorber structure. The EH performance of the designed 3 x 3 array structure was measured by an experimental setup conducted in an anechoic chamber. The results demonstrate a notably efficient electromagnetic EH, with resistive loads accounting for up to 96.89% of the total incident energy. The proposed design can potentially be used to develop wireless sensor network applications requiring efficient and compact harvesting systems.