In this study, a frequency selective rasorber (FSR) is proposed where a transmission band at a higher frequency is achieved besides the lower broadband absorption. The FSR is designed by combining the individual designs of broadband absorber and bandpass frequency selective surface (FSS). The broadband absorption is achieved by placing the resistive and ground layer at a distance of around λ/4 at center frequency. The unit cell of bandpass FSS is designed by etching a double cross slot. The performance parameters at the transmission band are improved by a modified double cross slot, wherein a quarter of the slot is replicated on each corner of the unit cell. The bandpass FSS replaces the ground plane of broadband absorber, in the design of proposed FSR. The proposed FSR is a polarization-independent structure exhibiting a broadband absorption from 3.1-8.7 GHz (94.91%) along with a transmission band at 11.4 GHz. The working principle of proposed FSR is illustrated by an equivalent circuit model. A range for higher transmission frequency is determined for the proposed FSR, by studying the effects of bandpass FSS parameters on the transmission performance. A prototype of the proposed FSR is fabricated, and the results are experimentally verified.

中文翻译：

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使用改进的基于双交叉槽的带通层具有更高传输频带的偏振不敏感频率选择性吸收器

在这项研究中，提出了一种频率选择性吸收器（FSR），除了较低的宽带吸收外，还可以实现更高频率的传输频带。FSR 是通过结合宽带吸收器和带通频率选择表面 (FSS) 的单独设计而设计的。宽带吸收是通过将电阻层和接地层放置在中心频率处大约 λ/4 的距离来实现的。带通FSS的晶胞是通过蚀刻双十字槽设计的。传输频带的性能参数通过改进的双交叉时隙得到改善，其中四分之一的时隙复制在单位单元的每个角上。在提议的 FSR 设计中，带通 FSS 取代了宽带吸收器的接地平面。- 8.7 GHz (94.91%) 以及 11.4 GHz 的传输频带。提出的 FSR 的工作原理由等效电路模型说明。通过研究带通 FSS 参数对传输性能的影响，为建议的 FSR 确定了更高传输频率的范围。制造了所提出的 FSR 的原型，并通过实验验证了结果。