密钥协商是量子密钥分配(QKD)的重要环节,影响着QKD的密钥率和安全距离。作为一种低信噪比时较为高效的密钥协商方案,多维协商算法被很好地应用在高斯调制连续变量QKD中,延长了通信距离。本文研究了二进制LDPC码在多维协商算法中的应用方案,进而扩展到多进制LDPC码。仿真表明,相比二进制LDPC码,利用多进制LDPC码能够使多维协商性能获得明显增益。
Secret key reconciliation is an important phase in quantum key distribution (QKD), which influences both the secret key rate and the speed of QKD. As an efficient reconciliation scheme under low SNR regime, multidimensional reconciliation scheme has been well adapted to the Gaussian-modulated continuous-variable QKD protocol and has extended the communication distance. We first investigate the application of binary LDPC Codes in the multidimensional reconciliation, and then extend to non-binary LDPC Codes. In the numerical simulations, we observe an obvious performace gain with our settings by using non-binary LDPC Codes, compared to binary LDPC Codes.