用于多维数据协调的双边类型LDPC码

Two-Edge Type LDPC Code for Multidimensional Reconciliation

在连续变量量子密钥分发(CV-QKD)多维数据协调中,协调效率和密钥传输距离取决于低密度奇偶校验(LDPC)码的纠错性能。在本研究中构造了一种拥有重复累积(RA)码中累积结构的高码率双边类型LDPC码(TET-LDPC),这种双边类型LDPC码在多维数据协调中相比于普通LDPC码可以得到更好的协调性能。经仿真结果可知,在信噪比为1.68 dB时,本文构造的码长为2×10~5的TET-LDPC的协调效率仍然可以达到98.48%,并得到了17.35 kb/s的安全密钥率。

In the multidimensional reconciliation process of continuous-variable quantum key distribution,reconciliation efficiency and the key transmission distance rest upor the error correction performance of LDPC code.Herein,a low-rate two-edge type LDPC code(TET-LDPC)with cumulative structure in repeated accumulation(RA)codes is constructed,This two-edge type LDPC code has better performance than canonical LDPC codes in the multidimensional reconciliation.According to the simulation results,when the signal-to-noise ratio is 1.68 dB,the reconciliation efficiency of the constructed TET-LDPC with a code length of 2×10~5 can still reach 98.48%,and the security key rate of 17.35 kb/s is obtained.