Frequency selective surfaces (FSSs) have attracted extensive attention for suppressing interference and improving channel quality and coverage by selectively transmitting or directionally reflecting electromagnetic waves in a specific frequency range in wireless communication networks. Therefore, FSS technology is considered to be another candidate after intelligent reflective surfaces (IRSs) in the sixth generation (6G) communication systems. In this paper, we provide a comprehensive investigation of the theory, design, and classification of FSS, and a contemporary overview of its vision and current applications in future 6G networks, as well as some emerging use cases of FSSs in 6G networks. Then, we describe the fundamentals and design methods of FSS from architecture, performance metrics, and experimental analysis methods and classify the relevant papers according to the FSS applications. Moreover, we review systematically the frequency selection characteristics, reflection, transmission, and absorption properties of FSS, and discuss the corresponding communication models. Additionally, we provide an overview of the vision and requirements for FSS-assisted 6G networks and summarize the FSS communication architecture and performance analysis towards 6G networks. Since the IRS technology is another metasurface candidate for 6G networks, we compare and review them with those for IRS-assisted 6G networks. Furthermore, we review some emerging use cases in 6G networks and present a new use case of adaptive spectrum allocation based on FSS. Finally, based on an extensive literature review and common weaknesses of FSS extant literature, we offer several challenges and some potential research directions.

中文翻译：

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6G 通信系统的频率选择性表面：当代调查


频率选择性表面（FSS）通过在无线通信网络中选择性地发射或定向反射特定频率范围内的电磁波来抑制干扰、改善信道质量和覆盖范围，引起了广泛的关注。因此，FSS技术被认为是第六代（6G）通信系统中继智能反射表面（IRS）之后的另一个候选技术。在本文中，我们对 FSS 的理论、设计和分类进行了全面的研究，对其愿景和在未来 6G 网络中的当前应用进行了当代概述，以及 FSS 在 6G 网络中的一些新兴用例。然后，我们从体系结构、性能指标和实验分析方法描述了FSS的基本原理和设计方法，并根据FSS应用对相关论文进行了分类。此外，我们系统地回顾了FSS的选频特性、反射、传输和吸收特性，并讨论了相应的通信模型。此外，我们概述了 FSS 辅助的 6G 网络的愿景和要求，并总结了 FSS 通信架构和 6G 网络的性能分析。由于 IRS 技术是 6G 网络的另一种超表面候选技术，因此我们将其与 IRS 辅助的 6G 网络的技术进行比较和审查。此外，我们回顾了 6G 网络中的一些新兴用例，并提出了基于 FSS 的自适应频谱分配的新用例。最后，基于广泛的文献综述和 FSS 现有文献的共同弱点，我们提出了一些挑战和一些潜在的研究方向。