一种基于伪逆平差理论的导航星座整网定轨方法

针对分布式单星自主定轨存在的次优解及滤波易发散等问题，结合整网伪逆平差理论和航天器轨道动力学定轨理论，提出一种导航星座整网自主定轨方法。讨论卫星网与大地自由网平差方法的区别，结合伪逆平差和卫星动力学定轨方法，建立导航星座整网自主定轨方法，并给出整网定轨基本流程，最后以典型Walker星座为例进行整网自主定轨仿真验证。结果表明，在初始位置误差1 m、星间测量噪声0.1 m、不考虑钟差的条件下，星座自主运行5 d，每颗卫星的定轨误差均小于0.8 m，星座平均定轨误差小于0.5 m,验证了该方法的有效性。

A Method Based on Pseudo-Inverse Adjustments of NavigationSatellite Constellation Orbit Determination

This paper is concerned with the problem of suboptimal and divergence in distributed filtering for autonomous orbit determination of satellite navigation systems. This paper proposes a concentrated filtering method, in which the navigation satellite constellation is considered as a whole, and essentially, theories of pseudo-inverse adjustment and spacecraft dynamic orbit determination are combined. First of all, differences between free network adjustment of geodetic survey and that of spacecraft network are discussed.Then a method of satellite constellation orbit determination which combines pseudo-inverse adjustment theory and satellite orbit dynamics is constructed, and the relevant technological process is given primarily. Finally, an example of network of typical walker constellations is given. The simulation results show that the user range error (URE) of any satellite is less than 0.8 m, mean URE of the satellite network is less than 0.5 m after five days’ autonomy operation.This verifies the efficiency of the method.