Design of ultra-wideband metamaterial absorber based on resistance films

A metamaterial absorber is proposed to meet the needs of wideband electromagnetic stealth, which completely covers C−Ka band and partially covers S-band and U-band. The absorber is composed of four square resistance films with different square resistance and foam medium substrates, and the multi-layer resistance film structure effectively expands the absorption bandwidth to both sides. The accuracy equivalent circuit is derived for better explaining the mechanism of the proposed absorber. The simulated results show that the proposed absorber provides over 88% ultra-wide absorption from 3.16 GHz to 51.6 GHz (relative bandwidth is 176.9%), and is stable to the incidence angle for both TE and TM wave. The metamaterial absorber is fabricated and tested, and the measured results are in good agreement with the equivalent circuit calculation and full-wave simulation results, which indicates that it has important application value in the electromagnetic stealth field.