基于软件定义量子通信的自由空间量子通信信道参数自适应调整策略  

Parameters adaptive adjustment strategy of quantum communication channel in free-space based on software-defined quantum communication

作　　者：卫容宇 聂敏 杨光 张美玲[1] 孙爱晶 裴昌幸 Wei Rong-Yu;Nie Min;Yang Guang;Zhang Mei-Ling;Sun Ai-Jing;Pei Chang-Xing(School of Communication and Information Engineering,Xi’an University of Post and Telecommunications,Xi’an 710121,China;School of Electronics and Information,Northwestern Polytechnical University,Xi’an 710072,China;State Key Laboratory of Integrated Service Networks,Xidian University,Xi’an 710071,China)

机构地区：[1]西安邮电大学通信与信息工程学院,西安710121 [2]西北工业大学电子信息工程学院,西安710072 [3]西安电子科技大学,综合业务网国家重点实验室,西安710071

出　　处：《物理学报》2019年第14期296-304,共9页Acta Physica Sinica

基　　金：国家自然科学基金(批准号:61172071);陕西省国际科技合作与交流计划项目(批准号:2015KW-013);陕西省教育厅科研计划项目(批准号:16JK1711)资助的课题~~

摘　　要：自由空间量子通信会受到雾霾、沙尘、降雨等自然环境的干扰.为提升环境干扰下量子通信的性能,本文提出了基于软件定义量子通信(software defined quantum communication,SDQC)的自由空间量子通信信道参数自适应调整策略.该策略通过对环境状态实时监测,根据预置在应用层的程序,对量子初始状态及单量子态存在时间等相关参数进行自适应调整,提高自然环境背景干扰下自由空间量子通信系统的保真度.仿真结果表明,在退极化、自发幅度衰变及相位阻尼三种噪声信道参数取值不同时,SDQC系统参数的最佳取值也不同.系统根据环境变化及业务需求,自适应地选择量子初始状态及单量子态存在时间,使量子保真度在通信过程中始终保持在峰值,有效提升了量子通信系统的适应能力及综合免疫力.Quantum communication in free space will be disturbed by natural environment, such as fog, dust, and rain, which is a difficult problem in the construction of quantum communication system. In order to solve this problem and improve the survivability of quantum communication system, we propose an adaptive parameter adjustment strategy for free-space quantum communication based on software-defined quantum communication(SDQC). Firstly, we propose a software-defined quantum communication model based on the idea of software defined networks. The architecture of SDQC is divided into four layers: transport layer, access layer, control layer, and management layer. The SDQC system sends the link information to the preset program at a management level through the real-time monitoring of channel state by the access layer. According to the link information, the management level issues instructions to the control layer to adjust the parameters such as the initial quantum state and the existence time of single quantum state, in order to improve the quantum entanglement and fidelity. Secondly, we analyze the relationship between quantum fidelity and parameters in SDQC system under three noise channels, i.e. depolarization channel, spontaneous amplitude decay channel,and phase damping channel. In the depolarized channel, the quantum fidelity F decreases with the increase of the error probability Pd of the qubit. When the error probability of qubit is certain, the system has the maximum quantum fidelity with the value of parameter x is 0.5. In the spontaneous amplitude decay channel,the quantum fidelity F decreases with the increase of the quantum state transition probability pt. When the transition probability of quantum state is certain, the higher the value of parameter x, the higher the fidelity will be. In the phase-damped channel, the quantum fidelity F decreases with the increase of the probability pc with which the qubit and the background interference equivalent quantum state have complete elastic scattering. When the pr

关 键 词：自由空间量子通信 软件定义量子通信 量子态 保真度 

分 类 号：O413[理学—理论物理] TN918[理学—物理]