新太阳光压模型在GNSS定轨中的应用

Application of new solar radiation pressure model in GNSS orbit determination

太阳光压摄动是影响卫星定轨中重要的误差源,在GNSS导航卫星精密定轨过程中使用最为广泛的光压模型为ECOM模型。为了探究几种ECOM模型及其适用性,该文以超快速星历为起算轨道,分析对比经典ECOM-1模型与最新13参数ECOMC模型对GPS/BDS卫星轨道的影响。结果显示:相较于ECOM-1模型,ECOMC模型在GPS定轨中精度有所提升,特别体现在径向精度提升,单天与三天弧段在径向的解算精度分别提升了12.73%和24.74%;在BDS定轨中,采用ECOMC模型,部分GEO卫星在径向方向单天精度有12.38%的提升,而对于IGSO与MEO卫星二者精度差异不大;分析可得,由于星体结构不对称引起卫星在沿太阳-卫星方向作用的偶数阶短周期谐波扰动,引入卫星-太阳方向偶数阶项的参数估计可提升卫星径向精度。

Solar radiation pressure perturbation is an important error source in satellite orbit determination.ECOM is the most widely used optical pressure model in the precise orbit determination of GNSS.In order to explore several ECOM models and their applicability,this article used ultra-fast ephemeris as the starting orbit,the influence of the classic ECOM-1 model and the latest 13 parameter ECOMC model on GPS/BDS satellite orbit were analyzed and compared.The results showed that:compared with the ECOM-1 model,the accuracy of ECOMC model in GPS orbit determination had been improved,especially in the radial accuracy.The radial accuracy of single day and three-day arc segments had been improved by 12.73%and 24.74%respectively.In BDS orbit determination,the single day accuracy of GEO satellite in radial direction had been improved by 12.38%,while the difference between IGSO and MEO satellite was not significant.The analysis showed that due to the asymmetry of the satellite structure,the even-order short-period harmonic disturbance of the satellite acting along the sunsatellite direction was caused.The introduction of the parameter estimation of the even-order term in the satellite-sun direction could improve the accuracy of the satellite in the radial direction.