亚毫米精度卫星激光反射器关键特性的研究及其应用

Satellite laser ranging is a high-precision satellite orbit measurement method, which plays an important role in satellite precise orbit determination, geodesy and other aspects. At present, the SLR precision is centimeter level, and only a few stations can reach millimeters for a small number of satellites. The error introduced by the laser retro-reflectors due to the distribution effect is the main obstacle to improve SLR precision. Research on the key characteristics of sub-millimeter precision satellite laser retro-reflector is the key to break through millimeters precision SLR, which is the demand of development and application of SLR..This project will research on the far-field diffraction pattern of laser retro-reflector array. And starting from the distribution effect of LRA, the accurate calculation model of reflection reference point correction and introduced random error of ranging will be established. Then the above research will be applied to design the international leading laser retro-reflectors with sub-millimeter precision for low, medium, high orbit satellites. The ranging random error and reflection reference point correction error introduced by them are less than 1mm, which can effectively improve the precision and accuracy of SLR, and provide on-board laser retro-reflector designs for millimeters precision SLR. Aiming at the large error introduced by the on-orbit LRAs, the research on extracting the ranging residuals of different corner reflectors in the laser reflector array will be carried out, which will be applied to SLR data preprocessing, so that the SLR precision of Shanghai Astronomical Observatory will reach millimeters level and reach the international leading level.

卫星激光测距是一种高精度卫星测轨手段，在卫星精密定轨、大地测量等方面发挥了重要作用。目前SLR精度仅为厘米级，只有少数台站对少量卫星可达毫米级，其中激光反射器因分布效应引入的误差是制约SLR精度提升的主要障碍。开展亚毫米精度卫星激光反射器关键特性的研究是突破毫米级精度SLR的关键，是SLR发展及应用的需求。.本项目将开展激光反射器阵列远场衍射光斑研究，并从激光反射器分布效应出发，建立精确的激光反射器反射参考点修正、引入的测距随机误差计算模型，应用上述研究设计性能国际领先的亚毫米精度低轨、中高轨卫星激光反射器，其引入的测距随机误差和反射参考点修正误差均小于1mm，可有效提高SLR精度和准确度，为毫米级精度SLR提供星载激光反射器设计。针对在轨激光反射器引入的误差大，开展激光反射器阵列中不同角反射器距离残差提取研究，应用于SLR数据预处理，使上海天文台SLR精度完全达到毫米级，达国际领先水平。

卫星激光测距是一种高精度卫星测轨手段，在卫星精密定轨、大地测量等方面发挥了重要作用。目前SLR精度仅为厘米级，仅有少数台站对少量卫星可达毫米级，其中激光反射器因分布效应引入的误差是制约SLR精度提升的主要障碍。.本项目建立激光斜入射角反射器的远场衍射光斑仿真模型、激光反射器等效反射点距离修正模型、激光反射器引入测距随机误差计算模型，作为亚毫米精度激光反射器设计依据。设计研制高精度四棱台激光反射器，成功应用于我国某重力卫星，在轨卫星激光测距精度优于1cm。设计研制亚毫米精度三棱台、单体大口径激光反射器，激光反射器引入的测距随机误差小于1mm，性能达国际先进水平。其中设计的单体大口径激光反射器将应用于我国某月球轨道卫星。建立Lageos卫星激光测距前沿回波数据提取模型，成功应用于数据预处理，上海站对Lageos激光测距度精由7.1mm提高到5.1mm，测距精度明显提升。项目的研究将推进我国毫米精度卫星激光测距的发展。