Optically transparent broadband and polarization insensitive microwave metamaterial absorber

A transparent metamaterial absorber with broadband microwave absorption and polarization insensitiveness is presented in this paper. Consisting of a two-layer closed square ring, one-layer patch-shaped indium tin oxide films, and a three-layer soda-lime glass substrate, the proposed absorber has advantages of broadband absorption with absorptivity higher than 85% ranging from 4.6 to 18 GHz, transparency, good polarization insensitiveness, wide-incident-angle stability, and high shielding efficiency. A prototype sample is fabricated and measured to demonstrate its excellent performance. The experimental results agree well with the numerical simulations.