This letter investigates physical layer security in intelligent reflecting surface (IRS)-aided VL communication (VLC). Under the point source assumption, we first elaborate the system model in the scenario with multiple legitimate users and one eavesdropper, where the secrecy rate maximization problem is transformed into an assignment problem by objective function approximation. Then, an iterative Kuhn-Munkres algorithm is proposed to optimize the transformed problem, and its computational complexity is in the second-order form of the numbers of IRS units and transmitters. Moreover, numerical simulations are carried out to verify the approximation performance and the VLC secrecy rate improvement by IRS.

中文翻译：

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智能反射面辅助VLC多用户物理层安全优化

这封信调查了智能反射面 (IRS) 辅助 VL 通信 (VLC) 中的物理层安全性。在点源假设下，我们首先阐述了多合法用户和一个窃听者场景下的系统模型，其中保密率最大化问题通过目标函数逼近转化为分配问题。然后，提出了一种迭代Kuhn-Munkres算法对变换后的问题进行优化，其计算复杂度为IRS单元数和发射机数的二阶形式。此外，还进行了数值模拟，以验证 IRS 的逼近性能和 VLC 保密率的提高。