Design of a Thin-Profile FR-4 Based Multi-Band Metasurface Absorber in S, C, X, and Ku Bands

作者：Merve Kurt · 发表于：Brilliant Engineering · 年份：2026 · DOI：10.36937/ben.2027.41158 · 研究领域：Advanced Antenna and Metasurface Technologies、Electromagnetic wave absorption materials、Metamaterials and Metasurfaces Applications

This study numerically presents the design of a multi-band metasurface-based microwave absorber designed to operate in the S, C, X, and Ku bands. The proposed structure exhibits simulated peak absorption values above 95% at resonance frequencies of 2.9 GHz, 6.3 GHz, 11.7 GHz, and 17.5 GHz, with narrowband fractional bandwidths of 0.64–1.14%. Polarization sensitivity was evaluated under normal incidence, while angular stability was assessed for Transverse Electric (TE) and Transverse Magnetic (TM) modes under oblique incidence. In addition, the structure was analyzed at oblique incidence angles of 15°, 30°, 45°, 60°, and 75° for TE and TM modes, showing that high absorption performance is generally maintained up to 60° incidence. To further interpret the absorption mechanism, effective permittivity and effective permeability were retrieved at the resonance frequencies; because the design is metal-backed, these parameters are treated as qualitative indicators of the electric and magnetic resonances rather than bulk constitutive parameters. Normalized impedance analysis confirms good matching with free space, with the real part approaching unity and the imaginary part approaching zero at all four resonances. In addition, electric field, magnetic field, and surface current distributions were analyzed at each resonance frequency, revealing anti-parallel current loops between the patterned resonator and the ground plane that confirm the magnetic-resonance mechanism underlying the a...