Design and Development of Broadband Absorptive Metasurface

Abstract

Metasurfaces has gained fascinating interest of researchers for radar cross-section (RCS) reduction applications. Cross polarization conversion metasurfaces and absorptive metasurfaces are widely used for RCS reduction. Passive metasurfaces exhibit single functionality at the required frequency band. Many multi-functional metasurface are proposed to achieve multiple functionalities at different frequencies. Comparative to conventional techniques of absorption, the metasurface offers compact size but narrow bandwidth. Generally, conventional absorptive metasurfaces can perform maximum absorption of 0.8 GHz bandwidth. Several absorptive structures are proposed where different absorptive resonators are integrated to achieve absorption at multiple distinct frequencies. Moreover, several research papers are focused on bandwidth enhancement of absorptive metasurfaces and researchers are pushing the boundaries of electromagnetic wave absorption in metasurfaces by employing lumped elements, complex multilayered structures, and inclusion of spacers in design techniques. However, achieving wider absorption bandwidth solely through lumped elements, without multilayer structures, remains an avenue for in-depth study especially if impinging is required to be absorbed at different incident angles. Thus, in this research single layer wide-band absorptive metasurface will be presented. The design will exhibit novelty in terms of structure, bandwidth and Angular Stability. The proposed design exhibits uniqueness in terms of structure, size and absorption ratio. The proposed single layer structure offers absorption greater than 80 %. The design is also angular stable for absorption up to 60 degree. The design has significant applications for scattering and absorption for RCS reduction techniques.