不同测站卫星质心不同改正对卫星激光测距定轨精度的影响分析

Effect Analysis of System-dependent Center-of-mass Correction on Precision of SLR Orbit Determination

数值模拟和理论分析均已显示,由于卫星形状效应,质心改正存在对测站系统运行模式的依赖性,即不同测站对卫星质心的改正是不同的。本文分析这种依赖性对卫星定轨精度的影响。长时间序列的统计结果表明,与全球统一测站卫星质心改正相比,采用不同测站卫星质心不同改正系统性地提高短弧定轨精度。对Lageos-1/2,平均提高约0.4mm;对Etalon-1/2,平均提高约0.6mm。在各种相关应用对卫星激光测距数据处理精度要求迈向毫米级的今天,有必要考虑不同测站卫星质心不同改正。

Numerical simulation and theoretical analysis have demonstrated the dependence of CoM（center of mass） corrections on system operating modes of SLR（satellite laser range） stations due to satellite signature effect,i.e.different CoM corrections should be applied on SLR data from different stations.The influence on POD（pricise orbit determination） exerted by such dependence is analyzed.Statistics over long-time series showed after adopting system-dependent CoM correction,the short-arc orbit determination precision has indeed undergone general improvement comparing to the situation of traditional global uniform CoM correction.The mean precision improvement is approximately 0.4 mm for Lageos-1/2 and 0.6 mm for Etalon-1/2.As the current requirements on SLR data processing for relevant applications have achieved sub-centimeter even towards millimeter level,it is necessary to take in the effect of system-dependent CoM correction.