Research Of Location Algorithm And Analysis Of GDOP Of The COMPASS Satellite Navigation System

COMPASS satellite navigation system is one of the four global navigation system, alongwith the great role playing by “BEIDOU” in the last, people and researchers have been paidmore and more attention to the development and application of COMPASS. The completionof COMPASS will make a great difference to the production and life, the scientific researchand national defense and army building. This paper researches the location algorithm thenmakes the simulation and evaluation performance of diversified algorithms in detail.First of all, the paper introduces the component of the four global positioning systems,the coordinate system and the time system used by them. The article also elaborates the basicoperating principle of every positioning system.Secondly, the orbit of the satellite constellation for navigation system is discussed indetails. Then, establish the mathematical model of BEIDOU and COMPASS. Then accordingto the satellite orbit theory, this paper explains how to calculate the position of every satellite,which is one of the measurements required by discovering their position of the users. Basedon this, this paper gives the situation of the design process of satellite orbit and the regioncovered by those satellites and how many satellites can be observed in a specific place.Thirdly, positioning algorithm is derived in details, including three algorithms each basedon the least square, the improved least square and the Kalman filter. In the derivation processdefines the Geometric Dilution Of Precision (GDOP), which is closely related to the results ofpositioning. Then a new method is raised on, which point out how to select the satellites.Based on this, this paper gives the situation of this three algorithms and the analysis of theresults.Finally, the hybrid positioning algorithms of GPS/COMPASS and GPS/COMPASS/Galileo are studied in the thesis and the mathematic modes of the two kinds ofmethod are established. Then simulate how many satellites can be observed in the hybridpositioning and each GDOP.