Compact polarization-sensitive hash-shaped metamaterial absorber for C and X band microwave applications

The present study describes the design and performance evaluation of a compact triple-band metamaterial absorber operating in the C- and X-band frequency ranges. The structure employs a hash-pattern resonator printed on an FR-4 dielectric substrate. Three resonant absorption bands are obtained at 7.27, 10.23, and 10.97 GHz, achieving absorptivities of 98.20%, 99.30%, and 99.12%, respectively. The electromagnetic response at these resonances is interpreted through analysis of the electric (E) field, magnetic (H) field, and surface current distributions to understand the absorption mechanism. The proposed absorber shows sensitivity to variations in polarization and angle of incidence. For experimental validation, a 13 × 13 array of the optimized unit cell is fabricated and characterized using a vector network analyzer, where the measured results are consistent with numerical simulations. Owing to its compact electrical size (0.279λ), thin profile (0.0194λ), and triple-band high absorption performance, the developed absorber is suitable for microwave sensing and detection applications.