An ultra-thin ultra-broadband microwave absorber for radar stealth

A broadband thin radar absorber based on a periodic frequency selective surface (FSS) is proposed. The proposed absorber comprises a resistive film structure printed on a polyethylene terephthalate (PET) substrate arranged periodically, a glass fiber dielectric layer (FR-4) located above and below the resistive film structure, respectively, and a metal base plate. At normal incidence, the proposed structure has greater than 90% absorption in the frequency range from 4 to 12 GHz, absorption bands include C-band, X-band, and Ku-band. When the angle of incidence is increased to 40°, more than 80% absorption can be guaranteed. Relative bandwidth of 130% achieved by multiple resonance. It is shown that this absorber offers significant competitive advantages over other broadband absorbers currently available. Experiments show that the measured results are in good agreement with the simulated results, providing an alternative solution for reducing electromagnetic interference from radomes and satellite stealth applications.Graphic abstract Structural optimization, experimental preparation, and simulation analysis of ultra-thin ultra-broadband absorber for radar stealth