Broadband Metamaterial for Visible and Infrared Transparent Microwave Absorption

In this paper, we present a broadband microwave absorber that is visible and infrared transparent, flexible, polarization insensitive, and angularly stable. It is designed with a three-layer structure consisting of a resistance film of indium– tin–oxide (ITO), Polymethylmethacrylate (PMMA), and a metallic grid. The proposed absorber can achieve more than 90% absorption in the frequency range of 8–18.34 GHz and greater than 95% in the range of 8.8-17.63 GHz, with a fractional bandwidth of 78.5%.