SPODS软件低轨卫星运动学精密定轨精度分析

Accuracy Analysis of Kinematic Orbit Determination for LEO Satellite Using SPODS Software

SPODS软件是西安测绘研究所自主设计和开发的多GNSS数据处理平台，目前该软件已经初步具备低轨卫星运动学定轨能力。本文简要介绍了星载GPS运动学定轨观测方程和软件的数据处理策略，详细介绍了带参数约化的最小二乘参数估计方法。收集2012年1月01～15日GRACE—A／B卫星的星载GPS数据进行定轨实验，结果表明，与JPL提供的精密轨道相比，GRACE—A卫星RTN分量的定轨误差RMS分别为0．037m、0．030m和0．023m，GRACE—B卫星RTN分量的定轨误差RMS分别为0．046m、0．033m和0．025m。

The SPODS software, designed and developed by Xi＇ an Research Institute of Surveying and Mapping, has the capability of kinematic orbit determination for LEO satellites. In this paper, the observation equation for LEO kinematic orbit de-termination and the data processing strategy with SPODS are presented and a detailed explanation is made on the method of Least - Square with parameter elimination. To evaluate the performance of SPODS for LEO kinematic orbit determination, GPS data of GRACE-A/B from January lst to 15th in 2012 were collected and experiments were carried out. The result shows ihat compared with the precise orbit of JPL, the RMS errors for GRACE - A are 0.037m, 0.030m and 0.023 m respectively in radius, track and normal components, and 0.046m, 0. 033m and 0.025m for GRACE - B.