A specific class of frequency selective surface (FSS) is the complementary frequency selective surface (CFSS) that has interesting characteristics such as high angular stability, multiple transmission and/or reflection bands, and the possibility of miniaturization. The analysis and design of this sort of structure are commonly performed using commercial software, which demands a high computational effort, impacting a longer optimization time. The equivalent circuit model combined with a cascading technique emerges as an alternative method to the use of these softwares, in the optimization of the physical dimensions of these structures, as they model the behavior of a CFSS with low computational effort and optimization time, in addition to being able to be implemented in various programming languages. Thus, this work proposes a CFSS analysis technique that combines the equivalent circuit method with the ABCD matrix. To the best of our knowledge, this is the first reported research on approximate techniques for CFSS analysis. The chosen geometry was the circular ring, due to high angular stability and polarization independence. The modeling of the equivalent circuit for patch and aperture geometries is presented. Some structures are simulated, and the results are compared with results obtained with the HFSS software. Finally, two prototypes are built to validate the analyses performed.

中文翻译：

---

互补频率选择表面分析技术的提出

一类特定的频率选择表面 (FSS) 是互补频率选择表面 (CFSS)，它具有高角度稳定性、多个传输和/或反射频带以及小型化的可能性等有趣的特性。此类结构的分析和设计通常使用商业软件进行，计算量大，优化时间较长。在优化这些结构的物理尺寸时，等效电路模型与级联技术相结合，成为使用这些软件的替代方法，因为它们以较低的计算量和优化时间对 CFSS 的行为进行建模，此外能够用各种编程语言实现。因此，本文提出了一种将等效电路法与ABCD矩阵相结合的CFSS分析技术。据我们所知，这是第一个关于 CFSS 分析近似技术的研究报告。由于高角度稳定性和偏振独立性，所选的几何形状是圆环。提出了贴片和孔径几何结构的等效电路建模。对一些结构进行了模拟，并将结果与​​使用 HFSS 软件获得的结果进行了比较。最后，构建了两个原型来验证所执行的分析。