A Two-Layer Secure Quantization Algorithm for Secret Key Generation With Correlated Eavesdropping Channel

When the eavesdropping channel has a certain correlation with the legitimate channel, the physical layer key is susceptible to eavesdroppers. To ensure the security of the secret key, we propose a two-layer secure (TLS) quantization algorithm in this paper. First, we model the correlation between the distance and the channel correlation and derive the joint probability density function of channel phase and the key capacity. Then, we describe the detail of the TLS algorithm and prove the validity of our algorithm. Finally, we evaluate the performances of the TLS quantization algorithm using two parameters-key rate and bit disagreement rate. The Simulation results verify the effectiveness of the algorithm.