Low‐Profile Fabric‐Based Ultra‐Wideband Metamaterial Absorber Design

Wearing electromagnetic protective equipment enables the absorption or reflection of electromagnetic waves that are incident on the human body, thereby reducing the risk of health issues associated with electromagnetic pollution. Although fabric‐based metamaterial absorbers can overcome the drawbacks of traditional electromagnetic shielding gear, such as excessive weight and low efficiency, achieving broadband absorption under low‐profile conditions remains challenging due to the inherently low dielectric constants of fabric materials. This study proposes a lightweight metamaterial absorber utilizing wool felt as the dielectric substrate and a polyethylene (PE) conductive film as the resonant layer for the frequency‐selective surface (FSS). Leveraging the excellent conductivity and high sheet resistance of the PE film, the nested square‐ring structure of the FSS exhibits strong resonant behavior. As a result, the absorber demonstrates absorption rates exceeding 90% across the 3.91–27.52 GHz frequency range, achieving a relative absorption bandwidth of 150.24% with an overall thickness of only 0.109 . Experimental measurements in a microwave anechoic chamber validate the absorber's angular and polarization insensitivity, in conjunction with excellent flexibility that maintains high absorption efficiency even under mechanical deformation. Furthermore, numerical simulations confirm that the absorber retains stable performance under humid environmental conditions.