中文摘要：

在一个三节点MIMO窃听网络中，针对窃听方发送恶意导频干扰，提出了一种基于分段导频发送和人工噪声的物理层安全传输方案。首先将导频发送长度分为n段，合法接收方只选取其中的m段发送导频信号。发送方利用rt—m段接收信号获取窃听信道的近似估计，并用其消除m段信道估计中的窃听信道部分。然后，发送方设计预编码矩阵并同时发送信号和人工噪声，实现信号的安全传输。仿真表明，当干扰功率为100mw时，所提方案下的安全速率平均提高了1．34bit／s／Hz。

英文摘要：

In a three-node Muhiple Input Multiple Output（MIMO） wire-tap network, this paper proposes a physical layer security transmission scheme based on the fragmented pilot transmission and the artificial noise according to the malicious pilot contamina- tion. First, the pilot transmission length is divided into n segments, and the legitimate receiver only uses m segments of them to transmit the pilot. Then, the transmitter obtains the approximate estimation of the eavesdropping channel based on the n-m seg- ments received signal and eliminates the eavesdropping channel part in the channel estimation results of the m segments received signal. Besides, the transmitter designs the precoding matrix and transmits both the signal and the artificial noise, realizing the se- cure transmission. Finally, the simulation results show the average security rate of the proposed scheme improves 1.34 bit/s/Hz when the jamming power is 100 mW.