Use Of Regional Network Data To Determine The Gps Satellite Orbital Methods And Related Software Design

The precise determination of orbit of the GPS satellites is the key technology to improve the precision of position and navigation. This paper mainly introduces how to determinate precise orbit using the data of civil regional network which is important to the research of orbit determination of the satellite navigation system of our country.Firstly this paper introduces some basic information about the determination of satellite orbit, including time systems, coordinate systems, the definition of these systems and the transfer between different systems. Then the two-body problem is discussed. It's the approximate description of the satellites movement. The position vectors, the velocity vectors and the orbital elements of the satellites have special relation which was introduced followed. The paper analyses the disturbed motions of the GPS satellites detailed such as the magnitude of the disturbing forces, the models of each disturbing force and the numerical solution of the equation of the satellites disturbed motion. The basic step of orbit determination by pseudorange is listed. Then Using the data of single day, three days and seven days to determinate orbit. The distribution of tracking stations influences the precision of orbit determination. Software with the function of primary orbit extrapolation is designed. Using this software we can choose set parameters and choose different models. Extrapolating the satellite orbit by broadcast ephemeris and precise ephemeris. The result shows that the error of initial value of the orbit will enhance rapidly. Finally the influence of different disturbing force model is detailed.