Xiong Jie, Lin Hai, Wang Kun, Wang Weilong, Yang Baoping
Opt Express. 2023 Nov 6;31(23):37818-37828. doi: 10.1364/OE.504446.
High-order bandpass filtering responses are highly desirable for frequency-selective surfaces (FSSs) in narrowband antenna/radar systems. In this paper, the design process of a reconfigurable dual-band FSS with second-order response is presented. Initially, the basic dumbbell-shaped resonator used in this design is theoretically investigated using the characteristic mode analysis (CMA) method to study the relation between geometric design parameters and the excited orthogonal resonance modes in different frequency bands. Then, an additional CMA process was performed on a unit cell with four such patch resonators arranged with 90-degree rotation between adjacent ones. This detailed analysis leads to a polarization-independent FSS design with a high-order dual-band response. Two of these composite resonators are combined back-to-back through coupling apertures on the middle layer. Finally, PIN diodes are loaded on separate layers to realize independent pass-band switching. The loading place of the PIN diodes is carefully chosen based on electromagnetic field analysis. A prototype was also fabricated and experimentally tested. Experimental results show that this FSS has two independently switchable passbands centered at 3 GHz and 4.8 GHz.
对于窄带天线/雷达系统中的频率选择表面（FSS）而言，高阶带通滤波响应非常理想。本文介绍了一种具有二阶响应的可重构双频FSS的设计过程。首先，使用特征模式分析（CMA）方法对本设计中使用的基本哑铃形谐振器进行理论研究，以研究几何设计参数与不同频带中激发的正交谐振模式之间的关系。然后，对一个单元进行了额外的CMA分析，该单元由四个这样的贴片谐振器组成，相邻谐振器之间以90度旋转排列。这种详细分析得出了一种具有高阶双频响应的与极化无关的FSS设计。其中两个复合谐振器通过中间层上的耦合孔背对背组合。最后，PIN二极管加载在不同层上以实现独立的通带切换。基于电磁场分析仔细选择了PIN二极管的加载位置。还制作了一个原型并进行了实验测试。实验结果表明，该FSS具有两个分别以3 GHz和4.8 GHz为中心的可独立切换的通带。
