An analysis of the wide area differential method of geostationary orbit satellites

• Published in: Science China. Physics, mechanics & astronomy Vol. 52; no. 2; pp. 310 - 314
• Main Authors: Cai, ChengLin, Li, XiaoHui, Wu, HaiTao
• Format: Journal Article
• Language: English
• Published: Heidelberg SP Science in China Press 01.02.2009; Springer Nature B.V
• Subjects: area; Astronomy; Classical and Continuum Physics; clock; differential; Dilution; ephemeris; errors; geostationary; Geosynchronous orbits; Global positioning systems; GPS; Mathematical analysis; method; Observations and Techniques; orbitsatellite; Physics; Physics and Astronomy; precision; Range errors; satellite; Satellites; Time synchronization; wide; geostationary orbitsatellite; dilution of precision; satellite clock errors; satellite ephemeris errors; wide area differential method
• ISSN: 1674-7348; 1672-1799; 1869-1927; 1862-2844
• DOI: 10.1007/s11433-009-0036-y

This work aims to obtain a wide area differential method for geostationary orbit (GEO) constellation. A comparison between the dilution of precision (DOP) of four-dimensional (4D) calculation including sa- tellite clock errors and ephemeris errors and that of three-dimensional (3D) calculation only including ephemeris errors with the inverse positioning theory of GPS shows the conclusion that all the 3D PDOPs are greatly reduced. Based on this, a basic idea of correcting satellite clock errors and ephem- eris errors apart is put forward, and moreover, a specific method of separation is proposed. Satellite clock errors are separated in a master station with time synchronization, and all the remaining pseu- do-range errors after the satellite clock errors have been deducted are used to work out ephemeris corrections of all GEO satellites. By a comparative analysis of user positioning accuracy before and after differential, the wide area differential method is verified to be quite valid for GEO constellation.