连续变量量子密钥分发中的最小二乘相位估计算法  

Least Square Algorithm for Phase Estimation in Continuous-Variable Quantum Key Distribution

作　　者：黄彪 麻甜甜 黄永梅[1,3] 彭真明 Huang Biao;Ma Tiantian;Huang Yongmei;Peng Zhenming(Key Laboratory of Optical Engineering,Institute of Optics and Electronics,Chinese Academy of Sciences,Chengdu,Sichuan 610209,China;School of Information and Communication Engineering,University of Electronic Science and Technology of China,Chengdu,Sichuan 610054,China;University of Chinese Academy of Sciences,Beijing 100049,China;Department of Basic Platform,Southwest Communication Institute,Chengdu,Sichuan 610041,China)

机构地区：[1]中国科学院光电技术研究所光束控制重点实验室,四川成都610209 [2]电子科技大学信息与通信工程学院,四川成都610054 [3]中国科学院大学,北京100049 [4]西南通信研究所基础平台事业部,四川成都610041

出　　处：《激光与光电子学进展》2021年第11期349-354,共6页Laser & Optoelectronics Progress

基　　金：国家自然科学基金(61775030,61571096,U1738204);中国科学院光束控制重点实验室基金(2017LBC003)。

摘　　要：为了提高连续变量量子密钥分发的参考相位估计精度,提出了基于最小二乘的参考相位估计方案。利用相位慢漂移的二阶相关特性和最小二乘估计原理,在接收端对多个参考脉冲的相位测量结果进行二次多项式拟合估计,从而抑制相位噪声的影响。仿真结果表明,相比于块平均估计法,基于最小二乘的参考相位估计算法能够更好地适应相位漂移变化,降低参考相位估计的均方误差,从而提高系统的安全密钥率。To improve the accuracy of reference phase estimation in the continuous-variable quantum key distribution,a scheme of reference phase estimation is proposed,which is based on the least square method.Utilizing the second-order correlation characteristics of slow phase drift and the least-square estimation theory,the phase measurement results for a group of reference pulses are fitted by a quadratic polynomial at the receiver to suppress the effect of phase noise. The simulation results show that the least square phase estimation algorithm,compared with the block-averaging estimation algorithm,is better adapted to phase drift variation,so that the mean square error of reference phase estimation can be reduced and the secret key rate of the practical system can be improved significantly.

关 键 词：量子光学 量子通信 连续变量 量子密钥分发 参考相位 最小二乘估计 

分 类 号：O431.2[机械工程—光学工程]