Design and Analysis of a Compact Ultra-Thin Metamaterial Absorber for Microwave Sensing Applications

This study presents the design and analysis of a compact, ultra-thin metamaterial absorber (MTM-A) optimized for microwave sensing applications. The unit cell is constructed on FR-4 substrate of 0.8 mm, ensuring low-cost fabrication without compromising performance. The proposed structure exhibits a strong absorption peak at 6.45 GHz within the C-band, with an absorption rate exceeding 99% and a significantly low reflection coefficient. This indicates minimal electromagnetic energy loss and reduced signal distortion, thereby ensuring high signal integrity within the operational frequency range. To evaluate its effectiveness in sensing applications, the absorber was analyzed with varying dielectric materials, demonstrating sensitivity changes in permittivity and conforming to its potential for solid material characterization in microwave regimes. The simulated results indicate that the proposed MTM-A can be effectively utilized in diverse sensing applications, including those in industrial and medical domains.