双星定位系统及其备份星在近地卫星联合定轨建模中的应用

Application of the Double-star Positioning System and Its Backup Satellite in Integrated Orbit Determination Modeling for LEO Spacecraft

建立了基于双星定位系统距离和观测数据的近地卫星联合定轨模型，设计了相应的数值融合联合定轨算法；为进一步提高近地卫星定轨精度，考虑融合双星及备份星距离和观测数据，建立了基于双星和备份星的近地卫星联合定轨模型及实现算法，并针对不同仿真条件进行了联合定轨仿真实验。仿真计算结果表明，联合定轨方式较传统近地卫星精密定轨方式可以更好地抑制双星星历误差对近地卫星定轨精度的影响，近地卫星和双星的定轨精度均得到了一定程度的提高；同时，融合备份星观测数据的近地卫星联合定轨精度得到进一步改善，达到5．17m。

An integrated numerical fusion LEO satellite orbit determination model is established based on the range and observation data of the Double-star positioning system. To further improve the orbit determination accuracy for LEO spacecraft, an integrated LEO satellite orbit determination model and implementation algorithm are established by combi- ning the range and observation data of two prime and one backup satellites of the Double-star system. Simulation results under different conditions show that the integrated orbit determination method better minimizes the impact of ephemeris error of Double-star satellites on the orbit determination accuracy for LEO spacecraft compared with other traditional LEO satellite orbit determination methods. As a result, the orbit determination accuracy of both LEO spacecraft and the Double-star system is improved. Integrated LEO orbit determination accuracy by incorporating observation data of the backup satellite is further improved to 5.17 meters.