Design, fabrication and characterization of stacked layers planar broadband metamaterial absorber at microwave frequency

The design, simulation, fabrication, and measurement of an ultra-wide spectral band metamaterial absorber were investigated in this paper. The unit cell consisting of three loop copper layers were printed on FR-4 epoxy dielectric substrate, and the top layer was Teflon. By stacking a number of one-layer structures on top of each other, a multi-layered structure was generated with a thickness of 3.7 mm. Results of the recursive method and the simulations showed a high absorption for wide angle of incidence up to 60° at TM and TE modes. The absorption at normal incidence was strong in the frequency range of 5.64–21.16 GHz numerically. The proposed structure was fabricated. The experimental results showed a good correspondence with the simulated results. Importantly, the design can be extended to other frequencies, such as terahertz, infrared, and optical frequencies.