中文摘要：

根据基于放大转发的双向中继信道的特性，该文利用时分系统无线多径信道的互易性和卷积运算的交换律提取密钥，使得密钥可以在信道估计时生成，而无需预先进行分配。由于信道的稀疏多径特性，采用基于压缩感知的重构算法对信道状态信息进行估计，提出了基于多径相对幅度和基于多径相对相位的密钥生成方案进行密钥的生成，并与基于多径相对时延的密钥生成方案进行了比较。仿真结果表明，3种方案均可以达到较高的密钥生成一致性，解决了第三方窃听的问题，保证了物理层通信的安全。

英文摘要：

According to the characteristics of two-way amplify-and-forward relay channel, this paper extracts secret key by exploiting the reciprocity of wireless multipath channel in time division system and the commutative law of convolution operation. So, the secret key can be generated with the channel estimation to overcome the drawback of the key pre-distribution mechanism. The recovery algorithm based on compressive sensing theory is used for channel estimation because of the sparsity of the wireless multipath channel. This paper proposed two new schemes based on the relative-amplitude and the relative-phase for secret key generation and compared them to the scheme based on the relative-delay. Simulation results show that all three schemes can achieve high key generation consistency probability, and present eavesdropping by the third party to ensure the security of the physical layer communication.