ULTRA-THIN, NON-METALLIC AND FLEXIBLE METAMATERIAL ABSORBER FOR X-BAND APPLICATIONS: DESIGN AND FABRICATION

Dipangkar Borah, Nidhi S. Bhattacharyya

Abstract: With the fast advancement of wireless communications and rapid increase of number of electronic systems, electromagnetic interference (EMI) have become more prominent and hence, minimization of EMI in both civil and military applications has led to extensive research on electromagnetic absorbers. Recently, metamaterial has been studied as EMI absorbers in different frequency regime because of its unique properties that exhibits excellent result as compared to conventional absorbers in different ways. Considering the advantages of metamaterial, here we present an efficient metamaterial absorber composed of expanded graphite based conducting layers and unit cells, separated by a flexible dielectric LLDPE substrate for X-band applications. Expanded graphite is synthesized, characterized and prepared to be used as unit cells and conducting layer. Microwave characterization of linear low density polyethylene (LLDPE) is carried out in X-band and developed as the substrate for flexible metamaterial absorber. Prior to the development, a numerical simulation is carried out using CST Microwave Studio to optimize the unit cell and the proposed absorber. Experimental validation of the designed absorber is done by employing waveguide technique. The proposed absorber showing more than 90% absorption at resonance frequency 10.10 GHz. The proposed absorber possesses the advantage of being ultrathin, lightweight, flexible, corrosive resistance and can be used for different conformal applications.

Keywords: Flexible metamaterial, LLDPE substrate, expanded graphite

DOI: https://doi.org/10.15623/ijret.2017.0613008