STAR-RIS Enabled Downlink Secure NOMA Network Under Imperfect CSI of Eavesdroppers
STAR-RIS Enabled Downlink Secure NOMA Network Under Imperfect CSI of Eavesdroppers
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DOI：
10.1109/lcomm.2023.3233980
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发表时间：
2023-03
期刊：
影响因子：
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通讯作者：
Hanbo Jia;Lin Ma;S. Valaee
中科院分区：
文献类型：
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作者：
Hanbo Jia;Lin Ma;S. Valaee
可重构智能表面（RIS）被认为是未来无线通信的关键技术之一。最近，同时传输和反射（星星）RIS被提出来克服传统的反射RIS的地理限制。在这封信中，我们建模的STAR-RIS使能的下行链路安全的非正交多址系统下不完美的信道状态信息（CSI）的窃听。具体而言，我们提出了基于块坐标下降的优化框架，以最大化最坏的保密率与基站和STAR-RIS系数的下行NOMA的主动波束形成，其中窃听者的CSI的不确定性是由S-过程转换。利用逐次凸逼近和罚函数方法解决了问题的非凸性。最后，仿真结果表明，该算法的最坏保密率优于传统的RIS和其他基准方案。
Reconfigurable intelligence surface (RIS) is regarded as one of the key technologies for the future wireless communications. Recently, simultaneous transmission and reflection (STAR) RIS is proposed to overcome the geographical constraint of the conventional reflection only RIS. In this letter, we model the STAR-RIS enabled downlink secure non-orthogonal multiple access systems under imperfect channel state information (CSI) of eavesdroppers. Specifically, we propose the block coordinate descent based optimization framework to maximize the worst secrecy rate with active beamforming of downlink NOMA at the base station and STAR-RIS coefficients, where the uncertainty of eavesdropper’s CSI is transformed by S-Procedure. The successive convex approximation and a penalty-based method are utilized to address the non-convexity of the problem. Finally, simulation results demonstrate that the worst secrecy rate of the proposed algorithm outperforms that of the conventional RIS and the other benchmark schemes.