摘要
星间链路ISL(Inter-Satellite Link)测距测速是导航星座自主定轨的主要数据来源。当星座仅涉及传统二体问题意义下的卫星时,ISL定轨是秩亏的。若引进地月系平动点轨道飞行器,则有望解决扩展星座的自主定轨。本文探讨了联合嫦娥四号的“鹊桥”中继卫星与北斗导航星座的自主联合定轨方法。分别构建了“鹊桥”与北斗混合星座中3类轨道卫星的星间测距单链路,数值分析表明,引入“鹊桥”卫星的定轨法矩阵的条件数约减小3个数量级,大大削弱了法矩阵的病态性。EKF自主定轨的滤波收敛后,除GEO的Z分量外,3类北斗卫星的自主定轨结果均可将初轨误差减小50%,但“鹊桥”中继星的轨道改进程度不如北斗卫星。若以“鹊桥”作为空间基准仅解算北斗导航卫星轨道,GEO定轨精度可达m级。仿真结果可为北斗导航星座星间链路的拓展应用提供一种新思路。
he Inter-Satellite Link(ISL)range and range-rate measurements are the primary data sources for autonomous Orbit Determination(OD)of navigation constellations.However,ISL autonomous OD is rank-defect,when only conventional two-body satellites are involved.If introducing LPO(Libration Point Orbit)spacecraft under the earth-moon system to build the extended constellation,this autonomous OD problem could be solved.This study discussed the autonomous OD method that brings Chang’e-4 relay satellite Queqiao,a kind of LPO spacecraft,into the so called extended BDS constellation.Firstly,the ISL single links are built,between Queqiao and three types of satellites of BDS constellation respectively.numerical simulations show that the condition number of the coefficient matrix of the normal equation can be reduced on the order of 3,namely the illness of normal matrix has been alleviated.Then,the OD algorithm with EKF is applied and the converged results demonstrate that the errors in all the positional component for the three types of BDS satellites can be reduced up to 50%of their initial errors,except for Z component of GEO.Generally,the orbital improvement of Queqiao is less than that of BDS satellites.Finally,Queqiao is assumed as a reference satellite and only the orbit of BDS satellite is to solve.The EKF result shows that the accuracy of GEO satellite overall is meter scale.The simulation results obtained by this study suggest a potential possibility for extended applications in BDS constellation's autonomous navigation.
作者
陈思睿
杜兰
CHEN Sirui;DU Lan(Information Engineering University,Zhengzhou 450001,China)
出处
《测绘科学技术学报》
北大核心
2020年第4期362-367,共6页
Journal of Geomatics Science and Technology
基金
国家自然科学基金项目(41774038,41804034)。
关键词
鹊桥
HALO轨道
北斗导航星座
自主定轨
星间链路
Queqiao
Halo orbit
Beidou satellite navigation constellation
autonomous orbit determination
inter satellite link
