基于随机调制实现光信道测量样本去相关分析  

Random modulation-based realization of optical channel measurement sample de-correlation analysis

作　　者：侯艺浩 娄岩[1,3] 陈纯毅 赵圣亚[1,2] 李辉 李琼 秦心怡[1,2] Hou Yihao;Lou Yan;Chen Chunyi;Zhao Shengya;Li Hui;Li Qiong;Qin Xinyi(NUERC of Space Optoelectronics Technology,Changchun University of Science and Technology,Changchun 130022,China;College of Opto-Electronic Engineering,Changchun University of Science and Technology,Changchun 130022,China;Chongqing Research Institute,Changchun University of Science and Technology,Chongqing 401135,China;School of Computer Science and Technology,Changchun University of Science and Technology,Changchun 130022,China)

机构地区：[1]长春理工大学空间光电技术国家地方联合工程研究中心,吉林长春130022 [2]长春理工大学光电工程学院,吉林长春130022 [3]长春理工大学重庆研究院,重庆401135 [4]长春理工大学计算机科学技术学院,吉林长春130022

出　　处：《红外与激光工程》2024年第4期243-253,共11页Infrared and Laser Engineering

基　　金：国家自然科学基金项目(62275033);重庆市自然科学基金项目(cstc2021jcyj-msxmX0457);吉林省科技发展计划项目(232655GX0108115018)。

摘　　要：从大气光信道中可以提取两个合法通信方用来加密其传输的机密信息的公共密钥。首先,为了打破湍流引起的光学波动的相关时间对每秒提取的不相关光信道测量样本的数量限制,提出了为合法通信双方配备随机调制的方法,并针对其实现测量样本去相关性进行了理论分析;其次,利用OptiSystem软件仿真分析了大气光信道水平路径传输距离为1 km,中湍流,调制方式为幅度调制条件下,合法通信方在无调制、单调制、双调制三种不同调制的情况下对光信道测量样本自相关性的影响。针对单调制的情形,分析了不同大气光信道传输系数相干时间、伪随机码生成速率、传输距离和信噪比对光信道测量样本自相关性的影响。结果表明,对比无调制情况,在相同采样间隔内,观测到的光信道测量样本的测量数据变化次数增多;同时施加随机调制的发射光信号,在小于湍流引起的光学波动的相关时间的采样间隔下,观测到的光信道测量样本,在滞后100个样本的延迟时间后的自相关性,从无调制情况下的0.676降低到单调制情况下的0.083和双调制情况下的0.035。Objective Based on channel-based key extraction technology,the reciprocal random channel is treated as a public random source from which shared keys are generated.During the optical channel transmission,the received optical signals may exhibit correlation due to unstable factors such as atmospheric turbulence,indicating a degree of correlation between adjacent signal samples.In order to extract highly random key sources from the optical channel,it is necessary to reduce the measurement rate of the channel state based on the correlation time of the channel,ensuring the lack of correlation between consecutive channel measurements.To some extent,the correlation time of optical fluctuations caused by turbulence limits the number of uncorrelated optical channel measurement samples that can be obtained per second.Therefore,it is necessary to perform decorrelation on the continuous observed optical channel measurement samples obtained by the legitimate party at a sampling interval shorter than the correlation time of optical fluctuations caused by turbulence.In this paper,a simulation experiment based on random modulation is constructed to achieve decorrelation of measurement samples,and the impact of random modulation on the autocorrelation of measurement samples is analyzed.Methods Based on existing relevant theories,an experimental system for measuring sample decorrelation based on random modulation has been designed.The schematic diagram of the transmitting and receiving terminal principles based on random modulation is shown(Fig.1),and theoretical analysis has been conducted(Fig.2).Through analysis,the impact of the normalized variance of the modulation signal source on the correlation coefficient of consecutive measurements is explained.Utilizing OptiSystem software,a simulation experiment of the sample measurement system based on random modulation in optical channels was constructed(Fig.3).Results and Discussions The power samples of received signals over time were analyzed under three conditions of no modulation

关 键 词：激光通信 自相关 随机调制 大气湍流 

分 类 号：TN929.12[电子电信—通信与信息系统]