Tri-Band Optically Transparent Absorption Metasurface for RCS Reduction

An optically transparent tri-band microwave absorption metasurface based on indium tin oxide (ITO) resistive films is proposed. The physical mechanism of the tri-band microwave absorption is revealed by analyzing the surface current distributions. Simulation results demonstrate that the proposed metasurface achieves over 90% absorptivity for vertically incident linearly polarized waves within three frequency bands from 8.85 GHz to 10.3 GHz, 18.63 GHz to 20.88 GHz, and 27.4 GHz to 30.45 GHz. The absorptivity at the peak frequencies of 9.51 GHz, 19.735 GHz and 28.84 GHz are 99.35 %, 99.78 % and 99.94 %, respectively, nearly perfect absorption across the three bands. Furthermore, the radar cross section (RCS) reduction characteristic of the metasurface under linearly polarized incident plane wave is investigated. The simulation results indicate that the proposed metasurface achieves RCS reduction of more than 1 0 d B in frequency ranges from 8.3 GHz to 9.7 GHz, 18.5 GHz to 21.5 GHz, and 27.5 GHz to 30.3 GHz. Additionally, the metasurface maintains excellent tri-band scattering suppression performance when conformed to cylindrical surface, which exhibits significant potential applications in stealth technology.