Combination of artificial materials with conventional pyramidal absorbers for microwave absorption improvement

Abstract This article addresses the combination of an artificial and conventional absorber materials in order to enhance its absorption properties and compactness. We demonstrate an increase of the absorption performance of the pyramidal absorbers by integrating a metamaterial layer. The latter is composed of two unit cells with multi resonance behavior between 2 GHz and 18 GHz. The simulation results of the hybrid material predict absorption for normal and oblique incidence of the electromagnetic wave at low and high frequencies depending on the wave polarization. Hybrid materials (metamaterial + conventional pyramidal absorbers) have been achieved using two pyramidal absorbers; the first one is a commercial absorber APM12/SIEPEL and the second one is the same material but with reduced dimensions. These absorbers are made of polyurethane foam loaded with carbon particles. The measurements show an increase of the absorption performance compared to the pyramidal absorber alone, even for the absorber with reduced dimensions.