Design of an optically transparent broadband metasurface absorber with fan shape

Aiming at the problem that transparent electromagnetic metamaterials have the advantage of absorbing electromagnetic waves in electromagnetic stealth, a broadband metasurface absorber composed of ITO-PET film and polymethyl methacrylate substrate is proposed in this paper. From the structural point of view, the top, middle and bottom layers of the absorber are ITO-PET films, and the adjacent two layers of films are sandwiched with thicker dielectric substrates. The top resonant absorbing structure is a fan-shaped indium tin oxide surface, which is easy to process and manufacture. The simulation results show that the absorber achieves more than 90% absorption rate in the frequency range of 4~18 GHz, covering the C, X and Ku bands related to electromagnetic stealth, and reaches 98.5% absorption peak at the resonant frequency of 10 GHz. The electric field density and power loss distribution on the surface of the simulated 10 GHz top-layer indium tin oxide are further monitored to reasonably explain the principle of electromagnetic wave absorption. In addition, the influence of structural parameters on electromagnetic wave absorption is analyzed by parameter scanning, and it is verified that it has good wide-angle incident and polarization insensitive characteristics.