基于外差检测原理的绝对测距性能理论研究  

Theoretical research for absolute distance measurement based on heterodyne detection principle

作　　者：王盟盟[1,2] 董瑞芳[1] 项晓[1,2] 刘涛[1] 张首刚[1] 

机构地区：[1]中国科学院国家授时中心,西安710600 [2]中国科学院大学,北京100039

出　　处：《仪器仪表学报》2016年第8期1861-1868,共8页Chinese Journal of Scientific Instrument

基　　金：国家自然科学基金(91336108;11273024;61127901);国家自然科学基金青年科学基金(11403031);中科院科技创新"交叉与合作团队"项目(中科院人教字(2012)119号);中科院科研装备研制项目和中组部"青年拔尖人才支持计划"(组厅字[2013]33号)项目资助

摘　　要：基于双光学频率梳外差原理测距将长模糊距离、高精度和高更新率3个关键测距特性完美结合,使测量性能能够满足航空航天、科学研究和工业生产等众多领域的需求。然而所使用的双光学频率梳的脉冲时域宽度、重复频率及相对差值、脉冲的固有时间抖动等特性都将会影响测距的性能。对基于双光学频率梳外差原理测距进行了全面的理论分析,并数值模拟了数据脉冲宽度、双光学频率梳重复频率差、啁啾参量、定时噪声、脉冲类型等各因素对测距性能的影响。模拟结果在数值上验证了奈奎斯特采样定律对测距精度的显著影响,表明实验中数据脉冲宽度和重频差的选择应严格满足奈奎斯特采样定律;当飞秒脉冲序列存在一定的时间抖动时,重频差越小,测距性能越差;而脉冲的啁啾特性可转化为脉冲宽度的影响,随着啁啾的增大脉冲宽度被压窄,奈奎斯特采样频率对应的重频差临界值也会变小。通过上述数值分析,为研究人员在特定实验条件下优化测距性能提供了重要指导。Absolute distance measurement technology based on heterodyne detection principle of dual optical frequency combs （OFC） perfectly combines three key distance measurement characteristics of large ambiguity range, high precision and fast update rate together, which makes the ranging performance meet the requirements of aeronautics and astronautics, scientific research and industrial manufacturing, etc. However, the characteristics of the used dual OFCs, such as time domain pulse width, repetition rate and the relative difference between the two combs, as well as the inherent pulse timing jitter will influence the ranging performance. In this paper, the fundamental model for laser ranging based on heterodyne principle of dual OFCs is built. Based on this model, the theoretical analysis for absolute distance measurement is implemented; and the influences of data pulse width, the difference of repetition rates of dual OFCs, chirp parameters, timing noise, pulse type and etc. on ranging performance are numerically simulated. The simulation results digitally verify the remarkable influence of Nyquist sampling theorem on ranging precision; thus, the selection of the data pulse width and the repetition rate difference should strictly meet the Nyquist sampling theorem in the experiment. In the presence of certain timing jitter of the femto second sampling pulse train, the smaller the repetition rate difference is, the poorer the ranging performance will be. The chirping feature in the data pulse train will be finally transformed to the influence of the pulse width. With the increasing of the chirp, the pulse width becomes nmaower, the critical value of the repetition rate difference corresponding to Nyquist sampling frequency will become smaller. The above numerical analysis provides an important guidance for optimizing ranging performance under specific experimental condition.

关 键 词：绝对距离测量 光学频率梳 外差原理 测距性能模拟 

分 类 号：TH741[机械工程—光学工程]