地面基准站网与星载GNSS融合的高中低轨卫星联合精密定轨

下一代导航系统拟纳入低轨卫星（LEO）作为增强和备份。研究了地面基准站网与星载GNSS融合的高中低轨卫星联合精密定轨（POD）理论与方法，基于实测国际地面站（IGS）和低轨卫星星载GNSS数据，通过建立高精度动力学模型和观测模型，根据全球测站和区域测站两种情况进行了导航星与低轨星的联合精密定轨试验。结果表明，联合定轨可同时获得导航星和低轨星厘米级的定轨精度。低轨星作为高动态天基测站，对导航星定轨精度的提升程度可达20%~90%。

Integrated Precise Orbit Determination of High, Medium and Low Earth Satellites Using Ground Station Network and Spaceborne GNSS Receiver Data

The next-generation navigation system is proposed to incorporate Low Earth Orbit (LEO) satellites as an enhancement and backup. The theory and method of integrated Precise Orbit Determination (POD) of high, medium and low orbit satellites using ground station network and spaceborne GNSS receiver data is studied. A high-precision dynamic model and observation model are established, and the integrated POD experiments of navigation satellites and LEO satellites are carried out under the cases of global station and regional stations using real data. The results show that the integrated POD can obtain centimeter-level POD accuracy for both navigation satellites and LEO satellites simultaneously. As a high-dynamic space-based station, the LEO satellites can help improve the POD accuracy of navigation satellites by 20%~90%.