Design of super compact ultrathin perfect wide‐angle polarization independent metamaterial absorber for C, X, and Ku band applications

Abstract

AbstractThis article focuses on the design of super compact, polarization insensitive with wide angular stability, ultrathin triple‐band metamaterial absorber. The unit cell comprising patches achieves almost perfect absorption (close to 100%) at C, X, and Ku band thereby justifying the term perfect metamaterial absorber. The structure provides 99.96%, 99.98%, and 99.62% absorptivity at the 4.75 GHz (C‐band), 9.47 GHz (X‐band), and 14.40 GHz (Ku‐band), respectively. The dimension of the structure is super compact of the order of 7.2 × 7.2 × 0.8 mm3 along with the ultrathin profile. The unit cell thickness is 0.012 λlowest (where λlowest is at a lowest cut‐off frequency). The proposed absorber comprises an outermost ring, split ring, innermost ring and square line with triangle patches at the boundary. The combinational effect of rings and internal patch provides perfect absorption at designated frequencies. Further, equivalent circuit is explained for the proposed design. The absorptivity remains insensitive towards transverse electric and transverse magnetic polarized wave and exhibits matched absorption. Moreover, the stability of the proposed design is validated with the different incident (for TE and TM modes) and polarization angles. The results are found close to perfect absorption. Finally, the simulated results are validated with measured results and found in close agreement.