An optically transparent broadband metamaterial absorber for radar-infrared bi-stealth

Abstract An optically transparent broadband metamaterial absorber (MA) containing an air layer and a water layer is proposed, which can absorb broad-band microwave and reduce infrared radiation at the same time. As a proof, a structure consisting of indium tin oxide (ITO) frequency selective surface (FSS), air layer, water substrate and ITO backplane was firstly designed. The simulation reveal that the structure can absorb wideband microwave with an efficiency of over 90% in the 14.4 GHz to 39.4 GHz frequency band, and it is optically transparent. This is consistent with the experimental results. In addition, the use of the water circulation system can significantly reduce the infrared radiation, thereby achieving infrared stealth. Due to its versatility and excellent performance, the proposed design is expected to find extensive applications in multi-spectrum stealth, such as glass windows for stealth devices, camouflage, etc.