A Miniaturized Design of Frequency Selective Absorber for S, C and X bands

In this paper, a study for realizing a miniaturized frequency selective absorber (FSA) capable of wide performance in S, C, and X bands is presented. The proposed absorber consists of a resistive layer on which a hexagonal shaped ring resonator and lumped resistors mounted rectangular strips are printed. A wide range of absorption is achieved in the proposed study with 90% bandwidth ranging from 2.9 to 11.2 GHz, along with the miniaturized unit dimension of $0.074 \lambda \mathrm{L}$ (where $\lambda_{L}$ is associated with the lowest absorption frequency). The proposed structure is a 2-layer design comprising of 4 lumped elements per unit cell and a thickness of $0.079 \lambda_{L}$. The absorption process is thoroughly investigated through comprehensive parametric analysis.