Reconfigurable intelligent surfaces (RISs) have attracted the attention of academia and industry circles because of their ability to control the electromagnetic characteristics of channel environments. However, it has been found that the introduction of an RIS may bring new and more serious network coexistence problems. It may even further deteriorate the network performance if these new network coexistence problems cannot be effectively solved. In this paper, an RIS network coexistence model is proposed and discussed in detail, and these problems are deeply analysed. Two novel RIS design mechanisms, including a novel multilayer RIS structure with an out-of-band filter and an RIS blocking mechanism, are further explored. Finally, numerical results and a discussion are given.

中文翻译：

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RIS辅助无线通信的网络共存分析

可重构智能表面（RIS）因其能够控制通道环境的电磁特性而引起了学术界和工业界的关注。然而，已经发现引入 RIS 可能会带来新的和更严重的网络共存问题。如果这些新的网络共存问题不能得到有效解决，甚至可能进一步恶化网络性能。本文提出并详细讨论了RIS网络共存模型，并对这些问题进行了深入分析。进一步探索了两种新颖的 RIS 设计机制，包括具有带外滤波器的新型多层 RIS 结构和 RIS 阻塞机制。最后给出了数值结果和讨论。