Design of wideband metamaterial absorber using circuit theory for X-band applications

A broadband metamaterial absorber working in the X-band is designed and fabricated by 3D printing in this study. This structure is capable of nearly absorbing the power of incoming waves (more than 90%) in the frequency band starting from 7.1 to 13.8 GHz. This metamaterial absorber is designed based on an infinite array of conductive ribbons, and the thickness of the absorber is just 0.1 lambda for the minimum frequency (without considering the thickness of the ground layer). A circuit model and transmission line theory are used to design and explain the absorption principle of the proposed structure. Our novel design method is flexible and can be applied to other frequency bands. The satisfaction of the proposed absorber can be applied to many applications namely communication, electromagnetic shielding, radar and satellite. Furthermore, due to the flexibility of the substrate, the proposed absorber is also suitable for flexible applications in the X-band.