Quadruple Polarization Insensitive Multilayered Metamaterial Absorber

A quadruple, compact multi-layered metamaterial absorber operating in the frequency band of C, X, Ku is presented in this paper. The multi-layered structure is formed by integrating the nested circular rings as the top layer and combination of split ring resonators and rings as the lower layer. The absorptivity plot of individual layer as well as absorptivity plot of complete multi-layered structure, which is calculated by considering both co- and cross- polarized reflection co-efficients, are studied. The presented design resonates at four resonating frequencies of 7.68 GHz, 11.073 GHz, 11.329 GHz, 13.1 GHz with absorptivity of 98%, 95%, 91%, and 99% respectively and also provides a bandwidth of 2GHz at full width half maximum (FWHM). The absorptivity plot with respect to the variation of both phi and theta is plotted to investigate the behaviour about polarization sensitivity and oblique incidence. The surface current distributions and impedance plot have been explained for the origin of high absorption.