A Miniaturized Band-Notched Absorber for Wideband RCS Reduction

This paper presents a polarization-insensitive miniaturized band-notched absorber with a wide operating bandwidth. The proposed geometry is comprised of a resistive top layer, band-reflective middle layer, and a ground plane, separated from one another by air spacers. The structure exhibits an operational bandwidth of 132.7% where absorption band is spread across the frequency ranges of 2.48-5.23 GHz and 7.68-12.26 GHz, whereas a band-notch response is obtained in between the absorption bands. The proposed topology is also angularly stable upto 45^o for both TE and TM polarizations. In addition, the overall footprint of the unit cell geometry is very small having lateral dimensions of 0.08λ_L × 0.08λ_L and thickness of 0.085λ_L, where λ_L corresponds to the lowest absorption frequency. The prototype of the structure has been fabricated as well as experimentally verified.