基于主轴投影的空域加扰信号窃密算法  

Interception Algorithm for Spatial Scrambling Signals Based on Principal Projection

作　　者：刘璐[1] 金梁[1] 黄开枝[1] 

机构地区：[1]国家数字交换系统工程技术研究中心,河南郑州450002

出　　处：《信息工程大学学报》2014年第1期62-67,共6页Journal of Information Engineering University

基　　金：国家863计划资助项目(2001AA121071);国家自然科学基金资助项目(61176108)

摘　　要：针对现有的窃密算法计算复杂度高,抗噪性能差的问题,提出了一种基于主轴投影的窃密算法。首先证明了当窃听天线数大于或等于发送天线数时,空域加扰信号存在主轴方向。然后利用Fisher线性判别准则,求解出加扰信号的主轴方向,沿该方向的投影能够在保留信息成分的同时抑制人工噪声,从而实现信息获取。理论分析与仿真结果表明,与现有的MUSIClike窃密算法相比,主轴投影法的计算复杂度低5~8个数量级,抗噪声性提升6dB^10dB。The existing eavesdropping method has high complexity and poor anti-noise performance, which makes it unpractical. It is proved that the receiving scrambling signals have principal direction when the eavesdropper has equal or more antennas than the transmitter. The principal direction can be evaluated by the Fisher linear discriminant criterion. The artificial noise can be cancelled by pro- jecting the receiving signals along the principal direction, while the information components are still maintained, which can be used to decode messages. Simulations show that the Principal Projection algorithm has the benefits of lower complexity and better anti-noise performance compared with existing MUSIC-like algorithms.

关 键 词：无线物理层安全 人工噪声 空域加扰 信号盲估计 

分 类 号：TN918.82[电子电信—通信与信息系统]