A Lunar Navigation System Based on Earth GNSS and Lunar Navigation Stars

Abstract

The invention relates to a lunar navigation system based on the earth GNSS and the lunar navigation star, which belongs to the field of navigation technology. The present invention adds a navigation satellite to the lunar orbit, broadcasts navigation signals compatible with GNSS, combines the earth GNSS to improve the observation geometry of lunar users, and simultaneously establishes the relationship between the earth GNSS navigation constellation and the lunar navigation star and between the lunar navigation star and the lunar user The two-way time synchronization link solves the problem that the user's receiver clock error and radial position error cannot be decoupled, and improves the real-time positioning accuracy of lunar users. At the same time, radio beacons on the lunar surface are added to key areas of the moon, and navigation signals compatible with GNSS are broadcast to enhance regional navigation performance. On the basis of adding a small amount of lunar navigation resources, it can greatly improve the real-time performance and accuracy of lunar user navigation and positioning, provide real-time high-precision navigation services for orbiting the moon, fixed-point landing and return, and lunar surface inspections, and support anytime emergency situations. Maneuverable, and provide beyond-horizon moon-based space short-message communication.

Description

technical field [0001] The invention relates to a lunar navigation system based on an earth GNSS and a lunar navigation star, belonging to the technical field of navigation. Background technique [0002] The follow-up mission of lunar exploration has changed from "focusing on science and engineering technology" to "focusing on scientific research and resource application". Higher requirements are put forward for the autonomy, real-time performance and navigation accuracy of navigation in China. At present, the navigation technology of lunar exploration missions has great limitations in terms of autonomy, real-time performance and positioning accuracy. [0003] The GNSS system uses ranging and timing to realize space-based radio positioning, navigation and timing (PNT) functions, and can provide all-weather accurate three-dimensional position, three-dimensional velocity and time information for ground and low-orbit users. Although the GNSS system is mainly designed for grou...

AI Technical Summary

Problems solved by technology

[0004] The difficulty of applying GNSS to lunar navigation is: the space distance between the earth and the moon is long, the link attenuation is large, and the lunar users mainly receive GNSS side lobe signals, so the available GNSS signal strength is extremely low; GNSS satellites are mainly concentrated in the lunar users’ space. In the top area, the spatial distribution is extremely poor relative to the observation geometry of lunar users, resulting in large positioning errors

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