面向多智能反射表面的物联网安全传输算法

Secrecy Transmission of Internet⁃of⁃Things for Multiple Reconfigurable Intelligent Surfaces

智能反射表面(Reconfigurable Intelligent Surface,RIS)由于其结构简单、易于部署,被广泛认为是物联网的关键技术。由于算力的快速发展,现行的应用层加密已经不能满足下一代通信网在安全方面的需求。为了适应物联网的新特征,有必要引入新的安全传输技术。考虑到以上因素,系统研究了基于物理层安全的物联网安全传输技术,提出了一种高效的智能反射表面选择算法。通过理论分析得到所有智能反射表面单独辅助传输时的链路容量及窃听信道的容量,进而在保证系统安全容量的基础上采用尽可能少的智能反射表面参与传输。在全部智能反射表面中选择一个安全性能较高的子集传输,达到了传输复杂度和系统安全性能之间的平衡,从而改善智能反射表面辅助的物联网系统安全容量性能。仿真结果表明,该算法能够以较低的传输复杂度实现较好的系统安全性能。

Reconfigurable Intelligent Surface(RIS)has been widely considered as a promising technology for the Internet⁃of⁃Things(IoT),which has been proven to be easily deployed with uncomplicated structure.Due to the fact of rapid growing of computer power,conventional encryption algorithms in application layer could not satisfy the security demands of the next generation communica⁃tion networks.In order to adapt to new characteristics of IoT,it is imperative to introduce innovative technologies for the secrecy trans⁃mission.Considering above facts,the secrecy transmission of IoT has been systematically investigated,where physical layer security has been considered.An efficient RIS selection algorithm has been proposed to ameliorate the secrecy capacity performance of the multiple RIS assisted IoT.The capacity for each RIS assisted transmission link and the capacity for eavesdropping channel have been obtained from theoretical analysis,which has been used to implement the transmission under the satisfaction of system secrecy capacity with mini⁃mum number of RIS.Therefore a subset of RIS with better secrecy performance is selected from the whole RIS to balance the transmis⁃sion complexity and the system secrecy performance.Simulation results demonstrated that the proposed multiple RIS selection algorithm achieves better secrecy performance with a low transmission complexity.