【摘要】 在GPS定位与导航中,用户可以通过选择至少4颗可见卫垦的观测,得到测站位置和站钟差信息。卫星相对于测站的几何关系直接影响到定位和导航的精度。考虑用4颗卫星进行定位,在当前有一定的现实意义,在Kihara等人工作的基础上对四面体的性质进行了深入讨论,推导了4颗可见卫星构成四面体体积的计算公式,实例分析证明该计算公式更合理、更精确。更多还原

【Abstract】 In some special GPS navigation and positioning applications, it can be synchronously obtained sites’ positions and clock biases from four visible satellites. The selections of these four satellites have influence on the accuracy of navigation and positioning. The minimum GDOP can be realized for four symmetric distributed satellites with respect to the sites. The GDOP is inversely proportional to the volume of the tetrahedron formed by unit vectors from sites toward the satellites. In this paper, based on the work of Kihara, the amendment of the optimum geometry on tetrahedron is discussed deeply and induced the formula of tetrahedron, it is demonstrated that it is more reasonable and precisely in example.更多还原