GPS非差相位精密单点定位技术探讨

GPS Precise Point Positioning Using Undifferenced Phase Observation

探讨了精密单点定位的基本原理、处理方法、所涉及的误差改正及数据处理中的一些关键技术 ;采用直接内插IGS卫星精密星历的方法代替利用IGS跟踪站进行轨道精化方法计算卫星轨道参数 ,对现有精密单点定位计算方法进行了简化 ,使之更具有实用性。最后利用自主研发的精密非差单点定位软件计算和分析了实测数据。计算结果表明 ,经过大约 15min的初始化后 ,非差相位单历元的定位结果精确度在X、Y、Z方向上均优于 2 0cm。

To overcome these shortcomings in differential GPS positioning,a new technique called precise point positioning (PPP) has been developed.In this approach,the IGS precise orbits and satellite clocks are used together with the undifferenced dual_frequency pseudorange and carrier phase observations of one single receiver for precise geodetic point positioning.It provides a very efficient tool to access the terrestrial reference frame or LEO's orbit determination.Also it is the key technique to realize the Global RTK and the internet_based differential GPS positioning in the future.This paper describes the approach of PPP in detail,and then discusses some problems in data processing.Finally,it analyzes the experimental results,which show that the initial time of PPP is about 15 minutes and the accuracy of single epoch positioning can be better than 20cm in X,Y and Z components after initialization.