无准确初轨信息时星载GPS低轨卫星定轨方法研究

Research on methods of low-earth satellites orbit determination based on GPS without accurate preliminary orbit position

本文提出了适用于星载GPS低轨卫星定轨的一种精密自主定轨方法。该方法利用星载GPS观测资料直接解算GPS方程求得卫星初轨,避免了早期使用短弧资料定初轨时法方程的病态性的影响,为精密定轨提供了较准确的近似值,并以此展开观测方程进行精密定轨,保证了迭代过程的收敛,减少了迭代次数,节约了时间,适用于低轨卫星的自主定轨和实时定轨。

The method of low-earth satellites orbit determination based on GPS without accurate preliminary orbit position is proposed.By solving GPS observation equations directly,the relatively accurate preliminary orbit position is obtained.It avoids ill-conditioned existed in normal equation with short-arc observations to determine preliminary orbit formerly and ensures high solution precision.The theoretical analysis and numerical simulation results show that the times of iteration of solving precise preliminary state parameters with the method proposed in this paper is fewer and iterative convergence is ensured.The method can be used in autonomous and real-time orbit determination of space aircrafts.