一种具有良好带通性能的二阶频率选择表面设计与验证

高阶频率选择表面(FSS)具有工作带宽易控制、通带内插损小、带外抑制强、通带边缘上升性和陡降性好等特点。提出并设计了一种具有良好带通性能的二阶FSS。该FSS结构是由2层介质板上加载3层具有圆结构的金属层,最外2层为圆金属贴片,中间一层为开圆缝隙金属层。利用直线法对FSS结构进行分析计算,并加工实验样件对结果予以证实。结果表明:该3层FSS具有二阶单通带的特性,3 dB带宽为4.21 GHz,相对带宽为21％,通带平稳光滑,带内插损小,对不同入射角度、不同极化方式的电磁波保持很好的稳定性。

The Design and Validation of A Second-order FSS with Good Band-pass Performances

Based on that the high order band-pass frequency selective surface (FSS) has the advantages of bandwidth controllable flexibility, stable performance, flat pass band and low insertion loss, a second-order FSS with good band-pass performances is designed in this paper. The designed FSS is composed of two layers of dielectric boards loaded with three layers of metallic patterns sheets. The two outer layers are of circular metallic patches while the middle layer is of circular aperture. The straight-line method is used to analyze and calculate the structure of the FSS, and a test sample is fabricated and measured to verify the results. The experiment results show that such a three-layer FSS has the desired second-order band-pass properties,the 3 dB bandwidth is of 4.21 GHz, the relative bandwidth is 21%, and the pass-band is quite flat and smooth in which the insertion loss is low. Moreover, the FSS can keep stable performances under different incident angles and polarization states.