Design of High-Frequency Selective Rasorber with Wide-Angle Broadband

a novel wide-angle rasorber with a wide transmission window and two wide absorption bands at both sides of the transmission window based on an interdigital resonator is presented and investigated in this article. The rasorber consists of a metallic absorption layer (loss layer) and a metallic FSS transmission layer (lossless layer). The transmission channel is achieved by a staggered grid slot. An equivalent circuit model (ECM) is proposed to explain the fundamental operating principle of the FSR and how to achieve the characteristic of the transmission window within the absorption band. The simulated results show that a flat less than 1 dB transmission window can be obtained from 9.5-10.8 GHz, and the -10 dB absorption bands are 6.2-8.9 GHz and 13.7-22 GHz under TE polarization. The transmission bandwidth and absorption bandwidth of FSR under TE and TM are almost the same. At the same time, oblique incidence can reach 50 degrees, with good angular stability.