U Coupled Rotationally Repeated SRR Shaped Metamaterial Absorber for 5G and Multiband Applications

We suggest developing and analyzing a rotationally symmetric metamaterial absorber (MMA) in this paper for wide-angle, polarization-insensitive wireless systems. The MMA, which consists of a single-layered electric ring resonator (ERR) with a four-fold rotational symmetry form, is employed to achieve the required absorption. Between 3.5 and 15 GHz, four strong absorption peaks have been noticed. The absorption may be more excellent in the microwave spectrum at 3.5, 5.28, 7.8, and 13.82 GHz, respectively, as high as 99%, 98%, 92%, and 95%. Numerical analysis and electromagnetic responses characterize the wide-angle and polarization insensitivity to co- and cross-polar waves. The unit cell is subwavelength compact because its thickness and size are 0.02λ and 0.22λ at the lowest working frequency. With a mean of 99% absorptivity at 3.5, 5.28, 7.8, and 13.82 GHz, as well as conventional and oblique incidence up to 80° and 180°, accordingly, the absorber showed similar results for cross-polar waves. The absorber can be used for practical amateur 5G, aeronautical radio navigation services, ground-based tactical radar systems, etc.