In this paper, an energy-efficient precoding scheme is designed for multi-user visible light communication (VLC) systems in the context of physical layer security, where users' messages are kept mutually confidential. The design problem is shown to be non-convex fractional programming, therefore Dinkelbach algorithm and convex-concave procedure (CCCP) based on the first-order Taylor approximation are utilized to tackle the problem. Numerical results are performed to show the convergence behaviors and the performance of the proposed solution for different parameter settings.

中文翻译：

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带有机密消息的多用户可见光通信的节能预编码

本文在物理层安全性的背景下，为用户的消息相互保密的情况下，为多用户可见光通信（VLC）系统设计了一种节能的预编码方案。由于设计问题显示为非凸分数规划，因此利用Dinkelbach算法和基于一阶Taylor近似的凸凹过程（CCCP）来解决该问题。数值结果表明了不同参数设置的收敛性和所提出解决方案的性能。