一种基于预编码的MIMO无线隐信道

MIMO wireless covert channel based on precoding

物理层调制类无线隐信道将秘密信息转化为人工噪声传输,以避免被检测发现。在多输入多输出通信场景下,由于传输介质的开放性,检测方可以利用各天线信号存在相关性而发现隐信道。针对这个不足,提出一种基于预编码的多输入多输出无线隐信道。假设发送方与检测方均能获得两者之间多输入多输出信道状态信息,发送方可以利用该信道状态信息对生成的人工噪声进行预编码处理,以去除检测方接收到的多路信号之间的相关性。接收方可通过公开信道传输的该信道状态信息生成预编码矩阵,进而提取出秘密信息。仿真结果表明,所提出的多输入多输出无线隐信道相较于现有方法,去除了检测方接收到的多路信号之间的相关性,有效地提高了抗检测性,同时可靠性有了一定的提高。

To conceal the existence of secret information,the wireless covert channel established in modulation of the physical layer converts secret information into artificial noise for transmission.In multiple-input multiple-output(MIMO)communication scenarios,due to the openness of the transmission medium,the detector can use the correlation of each antenna signal to discover the covert channel.To solve this problem,this paper proposes a MIMO wireless covert channel based on precoding.Assuming that both the sender and detector can obtain the MIMO channel state information(CSI),the sender can use this CSI to pre-encode the generated artificial noise to remove correlation of the multiple signals received by the detector.The receiver can generate the precoding matrix through the CSI transmitted through the public channel,and then extract secret information.Simulation results show that compared with the existing method,the proposed MIMO wireless covert channel removes the correlation of the multiple signals received by the detector,and effectively improves the undetectability,and that the reliability has been improved to a certain extent.