Flexible metamaterial absorber with wide incident angle insensitivity for conformal applications

This Letter demonstrates design, simulation, fabrication and performance of a metamaterial (MTM) absorber having wide incident angle insensitivity for conformal applications in X-band region. The important feature of the proposed structure is achieving more than 90% absorptivity with very low thickness. In this design, an FR4 material having thickness 0.1 mm is used as a substrate. Hence, the overall thickness of the proposed MTM absorber is only 1/81 of the wavelength at the resonance frequency of 9.2 GHz. Also, the presented absorber is offering more than 80% absorptivity up to 50 degrees incident angle which is very much suitable for conformal applications where curved surfaces are involved. Designed MTM absorber has been fabricated and simulation results are experimentally verified.