基于星间测距的卫星自主定轨研究与仿真

Algorithm and simulation of satellite autonomous orbit determination based on cross-link range

摘要:

提出了一种利用星间距离信息和扩展卡尔曼滤波算法确定卫星的位置和速度的方法。利用STK软件建立GPS星座，将1颗目标卫星与3颗参考卫星之间的距离引入一定的误差作为星间观测值，利用扩展卡尔曼滤波算法实现卫星的自主定轨。并对算法进行了改进，利用几何准确度因子GDOP值控制参考卫星的选择，消除了误差峰值。运算结果表明改进后的算法有很好的收敛性，提高了定轨准确度。

Abstract:

An Extended Kalman Filtering algorithm of autonomous orbit determination is presented in this paper. This algorithm can determine the satellite position and velocity vectors using cross-link range information. The STK satellite software developed by the AGI Company is used to create the GPS constellation scene，and cross-link range is derived based on quasi-distance among GPS satellites．Peak value of error is decreased by using the value of Geometric Dilution Of Precision(GDOP) to replace reference satellite. The simulation results demonstrate that the precision of orbit determination is greatly improved.