A dual broadband metamaterial absorber with concentric continuous and split rings resonator structure

This paper presents the design, simulation and parametric analysis of a concentric continuous and split rings resonator (CCRR, CSRR) structure for a dual broadband metamaterial (MM) absorber. The MM structure unit cell consists of concentric circular split rings of same width and different radii and concentric continuous rings of different width and different radii arranged in four different quadrants. The three layered proposed MM absorber design has upper layer comprising of concentric continuous and split rings structured sub-cells separated by bottom laminated copper layer of FR-4 substrate. The proposed MM absorber is insensitive to any polarization state of incident EM waves due to highly symmetrical circular and split ring structures. The scattering parameter and absorption coefficient are obtained for the present MM absorber. The magnetic and electric fields are monitored to realize the behavior of MM structure. The dual broadband MM absorber has absorbance of 99% from 7.785 GHz – 8.475 GHz and absorbance of 98% from 11.835 GHz – 12.81 GHz. The absorption peaks for this MM absorber are obtained as 99.5%, 99.6%, 98.4% and 98.8% at 7.785 GHz, 8.475 GHz, 11.835 GHz and 12.81 GHz frequencies respectively for the normal incidence of EM waves. The high absorbance makes this MM absorber suitable for various microwave applications including airborne and radar signal absorption.