低轨卫星与星间链路增强的北斗卫星联合定轨精度分析

Analysis of the Accuracy of Beidou Combined Orbit Determination Enhanced by LEO and ISL

为提升区域地面监测站条件下北斗卫星定轨精度,面向日益丰富的北斗星载数据和即将实现的星间链路技术,提出了联合运用地面监测站数据、低轨卫星星载数据与星间链路数据的北斗卫星精密定轨方法。讨论了低轨卫星星载数据与星间链路数据增强对于导航卫星精密定轨的影响,重点从低轨卫星数量、轨位分布及星间链路等方面进行了仿真分析。结果表明:加入少量低轨卫星与区域监测站联合定轨即可显著提高导航卫星定轨精度约73%,钟差解算精度略有改进但不明显;同等数量且均匀分布的低轨星座,其轨位分布对联合定轨精度影响不大;加入星间链路数据可大幅提升导航卫星定轨精度,且改进效率高于低轨卫星。

In order to improve the precision of BeiDou orbit determination under the conditions of regional ground monitoring station and make good use of increasingly rich on-board data and upcoming ISL technology,a method of BeiDou precision orbit determination is proposed which combines the use of ground monitoring stations data,low earth orbit satellite(LEOs)data and Inter-Satellite Link(ISL)data.The effects of assisting data of LEOs and ISL on the precision orbit determination of navigation satellite are discussed.Simulation analysis is carried out mainly from the number of LEOs,orbit slot configuration and ISL.The results show that the orbit precision of BeiDou will greatly improve about 73% with a small number of LEOs,while improvement of clock bias is not remarkable;the uniform orbit slot configuration of the same number of LEOs has a modest effect on the accuracy of combined orbit determination;compared with LEOs,the increase of ISL will significantly improve the accuracy of orbit determination with a higher efficiency.