Aiming at the problem of few visible satellites and short visible time for LEO cooperative navigation constellation leading to the difficulty of positioning, this paper studies multi-epoch positioning method based on the idea of replacing time to space. Taking advantage of the characteristics of the LEO satellite, such as high angular velocity and high signal landing power, through limited time of navigation signal observation, the pseudo-range and Doppler frequency positioning algorithm based on least squares method is adopted to achieve reliable positioning of static or quasistatic users. On this basis, the paper analyzes the Cramer-Rao lower bound of the positioning error, and through simulation analysis based on the error ellipsoid theory, it is found that the single LEO satellite multi-epoch positioning error distribution shows strong directivity, and the size and distribution of the positioning error is related to the relative position of user and satellite track. Therefore, the paper suggests that the positioning error of single LEO satellite is not suitable to be divided into horizontal and vertical errors according to the error analysis method of GNSS because of the anisotropy of each direction, but should be described separately by the three directions of east, north and vertical. The paper can provide technical support for the system design and positioning application of future LEO navigation satellites.
Single Satellite Positioning Method and Error Characteristic Analysis of LEO Navigation Satellites
Lect. Notes Electrical Eng.
China Satellite Navigation Conference ; 2024 ; Jinan, China May 24, 2024 - May 26, 2024
2023-11-04
12 pages
Article/Chapter (Book)
Electronic Resource
English