基于伪随机脉冲估计的简化动力学卫星定轨方法

Reduced-Dynamics Satellite Orbit Determination Based on Pseudo-Stochastic Pulse Estimation

采用简化动力学模型和星载GPS非差观测值,通过在确定性卫星运动方程中引入伪随机脉冲参数,将确定性参数和伪随机脉冲参数一起估计,对CHAMP卫星进行精密定轨。定轨软件采用自行研制的CASMORD精密定轨软件,定轨结果与GFZ事后定轨结果以及SLR结果进行了比较与分析。结果表明,采用简化动力学方法对CHAMP卫星定轨,在X、Y、Z三个方向的均方根误差(RMS)基本一致,轨道位置精度优于10cm,与SLR比较,测距精度优于5cm,定轨结果可靠,验证了算法的可行性和软件的定轨精度。

The orbit of CHAMP satellite is determined based on reduced-dynamics model and zero-difference measurements onboard in this article.The pseudo-stochastic parameters are introduced into the satellite＇s deterministic motion equation and two kinds of parameters,i.e.deterministic parameters and pseudo-stochastic parameters,are calculated together in the process of orbit determination.Compared with GFZ＇s RSO（Rapid Science Orbit） and SLR（Satellite Laser Ranging） observations,orbit positioning accuracy is superior to 10 cm and ranging accuracy is within 5cm.Consequently,the feasibility of the algorithm and the orbit determination accuracy of the software are validated.