一种基于人工噪声的MISO相关信道物理层安全方法

现有基于人工噪声的物理层安全方法都假设信道是相互独立的,但是多天线通信系统中存在的信道空间相关性会降低系统安全容量。针对这一问题,设计了一种基于人工噪声的多入单出(MISO)相关信道物理层安全方法。通过合法用户信道参数的协方差矩阵得到发送端的信道相关矩阵,利用该矩阵与合法用户信道参数乘积的零空间作为人工噪声的生成空间,随机生成人工噪声对窃听方实现干扰。仿真结果表明,在存在信道空间相关性的情况下,本方法比现有方法的平均系统安全容量提高了约0.5 bit/s/Hz。

Physical layer security scenario using artificial noise in correlation MISO channel

Prior work on artificial noise approach of physical layer security has assumed the independency of different channels. However, in a practical multiple antenna system, the spatial correlation among channel taps would decline the security capacity. This paper explored a robust alternative for secure transmission on correlated multiple-input single-output(MISO) channel based on artificial noise. The channel state information between transmitter and the legitimate user could provide the correlated matrix of the spatial correlation. With the null space of the product of the correlated matrix and channel state information, the transmitter produced random artificial interference to prevent from eavesdropping. The simulation result indicates that the robust method improves the average secure capacity about 0. 5 bit/s/Hz with the proposed method when channel correlation exists.