中国空间科学技术 ›› 2021, Vol. 41 ›› Issue (1): 13-21.doi: 10.16708/j.cnki.1000-758X.2021.0002

• 研究探讨 • 上一篇    下一篇

基于扩展卡尔曼滤波的XPNAV-1卫星自主定轨算法研究

丁陶伟,帅平,黄良伟,张新源   

  1. 中国空间技术研究院钱学森空间技术实验室,北京100094
  • 出版日期:2021-02-25 发布日期:2021-02-02

An autonomous orbit determination algorithm of XPNAV-1 based on extended Kalman filtering

DING Taowei,SHUAI Ping,HUANG Liangwei,ZHANG Xinyuan   

  1. Qian Xuesen Laboratory of Space Technology,China Academy of Space Technology,Beijing 100094,China
  • Published:2021-02-25 Online:2021-02-02

摘要: X射线脉冲星导航1号(XPNAV-1)是全球首颗脉冲星导航专用试验卫星。利用该卫星观测的单颗脉冲星数据,采用几何约束方法,能够有效抑制轨道误差增长,但存在长时间定轨发散问题。针对XPNAV-1卫星拓展试验任务及脉冲星导航后续发展需求,利用多颗脉冲星的观测数据,研究基于扩展卡尔曼滤波(EKF)的卫星自主定轨算法。首先,建立该卫星的轨道力学模型和观测方程;然后,详细论述EKF滤波算法和分段式定常系统(PWCS)的可观测性分析方法;最后,通过综合分析XPNAV-1卫星的观测数据、脉冲星对该卫星轨道的覆盖性以及系统状态的可观测性,进行自主定轨算法试验。试验结果表明,基于EKF的自主定轨算法滤波过程收敛,验证了该算法的合理性和有效性。

关键词: XPNAV-1, 自主导航, 动力学定轨, 非线性滤波, 可观测性分析

Abstract: The world′s first dedicated pulsar navigation test satellite, X-ray pulsar-based navigation-1(XPNAV-1), was successfully launched by China in November, 2016. The satellite is operating normally in orbit, and a large amount of observation data has been acquired. The measured data of a single pulsar was used to verify the effectiveness of the satellite orbit improvement and the pulsar navigation system through the geometric constraint method. However, the longterm orbit determination process using a single pulsar had divergence problems. Based on the XPNAV-1 satellite expansion test mission and the need for subsequent development of pulsar navigation, the observation data of multiple pulsars was used to study the autonomous orbit determination algorithm of satellites based on extended Kalman filter (EKF). Firstly, the orbital mechanics model and observation equations of the satellite were established; secondly, the EKF filter algorithm and the observability analysis method of the piecewise constant system (PWCS) were discussed; finally, through a comprehensive analysis of the XPNAV-1 satellite observation data, pulsar coverage of satellite orbits and observability of system status, the autonomous orbit determination algorithm experiment was carried out. The test results show that the filtering process of the autonomous orbit determination algorithm based on EKF converges, which verifies the rationality and effectiveness of the algorithm.

Key words: XPNAV-1 satellite, autonomous navigation, dynamic orbit determination, nonlinear filter, observability analysis