A highly efficient deca-band metasurface absorber for diverse microwave applications

Abstract

We propose a highly efficient, deca-band, and single-layered metasurface absorber (MA) based on the idea of split-ring resonators (SRRs). The unit cell of the proposed MA is a combination of 2 × 2 symmetrically arranged meta-structured designs, each comprising long and short L-shaped SRRs, two concentric semi-circular rings, and two T-shaped conducting strips. The absorption phenomenon of the proposed structure is successfully demonstrated using the standing wave resonance theory (SWRT), detailed current distribution, and the electric field distribution analysis. The thickness of the proposed MA unit cell is 0.96 mm having 1/56, 1/41, 1/35, 1/21, 1/20, 1/18, 1/17, 1/13, and 1/12 respective free-space wavelengths and has compact unit cell dimensions of 0.018λo×0.018λo, where λo corresponds to the lowest absorption frequency. The proposed structure offers absorption peaks of more than 90% at 10 distinct frequencies to demonstrate its applicability in diverse microwave applications. It is shown in simulations and experimentally that the proposed MA is angularly stable up to 70˚and has polarization insensitivity behavior up to 90˚ for both TE and TM polarized waves. A good agreement between simulation and measurement results demonstrates the efficacy of the proposed MA in a wide range of microwave applications.