An inter-satellite dynamic ranging algorithm based on two-way time synchronization
Feijiang Huang1, 2, Jun Yang1, Xiaochun Lu3, 4, Qingxiao Shan1, Yongbin Zhou1, Jianyun Chen1, Zhuli Hu1
1College of Mechatronic and Automation, National University of Defense Technology, Changsha 410073, China
2Department of Electronics and Communication Engineering, Changsha University, Changsha 410022, China
3National Time Service Center, Chinese Academy of Sciences, Xi’an 710600, China
4Key Laboratory of Precision Navigation and Timing Technology, Chinese Academy of Sciences, Xi’an 710600, China
Inter-satellite precise ranging is the foundation for all aerospace application systems in realizing autonomous navigation. To acquire a high-accuracy inter-satellite range, this study investigates an inter-satellite dynamic ranging algorithm. Referring to the simulation of inter-satellite range variation rules in constellation, this study analyzes the negative impact of satellite motion on inter-satellite ranging and proposes corresponding improved methods to eliminate the major error caused by satellite motion. This algorithm solves the minimal error in inter-satellite range using a combination of inter-satellite range fitting polynomial and inter-satellite clock-offset fitting polynomial, both of which are generated by two-way time synchronization data. Simulation calculation results show that the accuracies of inter-satellite ranging can be controlled within 3m provided that simulation error is considered. The algorithm can be used to improve the accuracy of inter-satellite dynamic ranging of various aerospace application systems.