Artificial-Noise-Aided Precoding Design for Multi-User Visible Light Communication Channels

作     者：Pham, Thanh, V Hayashi, Takafumi Pham, Anh T. 

作者机构：Univ Aizu Comp Commun Lab Aizu Wakamatsu Fukushima 9658580 Japan Niigata Univ Dept Informat Engn Niigata 9502181 Japan 

出 版 物：《IEEE ACCESS》 (IEEE Access)

年 卷 期：2019年第7卷

页      面：3767-3777页

核心收录：

基　　金：JSPS KAKENHI [18J14290, 15K00134] Grants-in-Aid for Scientific Research [18J14290, 15K00134] Funding Source: KAKEN 

主　　题：VLC wiretap channel physical layer security artificial noise-aided precoding zero-forcing precoding 

摘      要：Recent developments in visible light communications (VLC) have focused on enhancing its security and privacy. This paper studies the physical layer security in VLC networks with multiple users when there is a single wiretap eavesdropper. In particular, our aim is to design the optimal artificial noise (AN)aided precoding scheme to improve the secrecy performance in terms of legitimate users and eavesdropper s signal-to-interference-plus-noise ratios (SINRs). The purpose of our AN-aided precoding design is to ensure a fairness of the legitimate users SINRs while impairing the quality of eavesdropper s channel as much as possible. Depending on the availability of the eavesdropper s channel state information (CSI) at the transmitters, there are generally two design strategies. When the eavesdropper s CSI is unknown to the transmitters (i.e., passive eavesdropper), the AN is constructed to be orthogonal to the users aggregate channel matrix. In case the eavesdropper s CSI is available (i.e., active eavesdropper), the AN design strategy is to keep the SINR of the eavesdropper below a certain predefined threshold. Aside from the general design, we also study a specific design with the zero-forcing (ZF) technique and compare its performance with that of the general design. In both designs, numerical results show that significant gaps between users and eavesdropper s SINR can always be achieved, thus guaranteeing a high secrecy performance. It is also observed that while the general design outperforms the ZF one in terms of the users SINRs, it does not result in lower eavesdropper s SINRs compared to the ZF design, especially in the low transmit power region.