一种OFDM系统信道密钥生成方法

提出了一种在正交频分复用(OFDM)系统中提取信道频率响应(CFR)表征信道特征，经过探测、量化、协商、一致性确认以及隐私放大生成信道密钥的方法。首先，利用OFDM系统多载波的优势，在各个子信道提取信道特征，并进行量化；然后，采用滑窗密钥生成机制以及分段校验，通过一次位置信息交互，高效地完成协商,生成初始信道密钥；最后，利用隐私放大函数生成信道密钥。所提方法通过滑窗生成大量密钥比特，以一轮协商代替多轮协商；只限定初始密钥最大长度，使得初始密钥在长度及信息两个维度保持随机化。

A channel frequency response based secret key generation method in OFDM systems

This paper proposes a method for channel key generation in Orthogonal Frequency Division Multiplexing(OFDM) systems through exploiting channel frequency response(CFR),quantization,reconciliation,confirmation and privacy amplification.Firstly,by utilizing the advantage of multi-carrier,channel characteristics are extracted in subchannels and quantization.Then,sliding window key generation mechanism and segment checking are used for initial channel key generation.The reconciliation process is accomplished efficiently with one single location interaction.Finally,privacy amplification function is used to generate channel secret key.With the proposed method,a large number of key bits are generated through the sliding window,multi-round reconciliation is replaced with a single round reconciliation,and limitting the maximum length of initial key makes initial key kept random both in length and information.