Development of A Novel Ultra-Wideband Textile-Based Metamaterial Absorber for mm-wave Band Applications

This work proposes an ultra-wideband Metamaterial (MM) absorber for smart electronic textile (etextile) applications. The design is based on a novel cell geometry composed of two combined letter patches (A&S) printed on a grounded textile substrate. This unit cell geometry is specifically developed and optimized for millimeter-wave (mm-wave) applications. In this study, different types of textiles are considered, namely, Felt, Denim, and Polyester, and the achieved -10 dB reflective fractional bandwidths are about 50.36%, 44.49% and 41.42%, respectively. A comparison between conventional counterparts PCB-based dielectrics (FR-4 and Rogers RT-5880) and textile-based fabrics (Felt, Denim, and Polyester) indicates that the bandwidths exhibited by textile fabrics are significantly wider. This study also demonstrates that the bending of textile-based materials has an inverse effect on the -10 dB bandwidth, as the material's surface curvature increases. The current design is more compact, thin, and more efficient in terms of absorptivity in comparison to other reported absorbers and structures in the literature. The obtained results can be considered promising for the development of ultra-wideband e-textile-based applications such as energy harvesting, health monitoring, and camouflage systems.