Orbit determination and time synchronization of spatial information network combining sparse regional ground stations
The development of global low earth orbit (LEO) satellite communication constellations and the technology advancement of global satellite navigation system (GNSS) orbit and clock determination lay a necessary foundation for moving the continuous operation reference system (CORS) to near-Earth space,...
Main Authors: | , , , , , , , |
---|---|
Format: | Article in Journal/Newspaper |
Language: | Chinese |
Published: |
Surveying and Mapping Press
2021
|
Subjects: | |
Online Access: | https://doi.org/10.11947/j.AGCS.2021.20210009 https://doaj.org/article/2a8c016cdac044b3a767096f7f9641f9 |
Summary: | The development of global low earth orbit (LEO) satellite communication constellations and the technology advancement of global satellite navigation system (GNSS) orbit and clock determination lay a necessary foundation for moving the continuous operation reference system (CORS) to near-Earth space, which is helpful to break through the limitation of ground reference station distribution and realize global space-based CORS positioning service with few regional ground stations. However,space information network has many different characteristics such as high dynamics, network reconstruction, and significant flexibility. How to determine the orbit of LEO satellites and time datum for a space information network with few regional ground stations is the key to realize global high-precision positioning service of the space-based CORS network. This paper studied the method of unifying space and time datum determination based on the backbone network and the access network strategy. Experiments show that an orbit determination accuracy of about 7 cm is achievable for GNSS and LEO satellites with only five ground stations in China,one in Arctic, one in Antarctica, and 12 LEO satellites. Based on the known precise orbit of space nodes, about 10 cm accuracy is realized for other LEO space nodes that did not participate in orbit determination. For the time synchronization of space information network, the inter-satellite and satellite-ground time comparison method is proposed with the strategy of network layering autonomy and new inter-satellite link. Results show that the time synchronization of 10 ns precision level can be achieved with communication signal system. |
---|