全球定位系统实时服务数据的精度分析

Accuracy Analysis of GPS Real-time Service Data

全球定位系统的广播星历轨道精度约为2m,钟差精度约为2ns,用于实时精密单点定位,精度不够理想。为了得到高精度的实时数据,国际全球定位系统服务机构从2013-04-01起推出实时计划。介绍了全球定位系统实时服务数据接收和修复的方法,并选取其中4个实时数据流数据,分析比较了全球定位系统卫星轨道和钟差的精度,与国际全球定位系统服务机构事后精密星历进行对比。发现全球定位系统卫星轨道在径向、切向、法向上精度都能达到厘米级,其中径向误差最小,可达2cm,切向误差最大,为8cm;钟差精度优于0.2ns。全球定位系统实时服务数据的精度完全满足实时精密单点定位的要求。

The orbit accuracy of GPS broadcast ephemeris is about 2mand the clock precision is 2ns,which is unsatisfac- tory to real-time precise point positioning.IGS provided real-time service in order to provide high-precision real-time data since April 1,2013.The receipt and recovery of GPS real-time data are introduced in this paper.The orbit and clock of GPS satel- lites from four real-time data streams were selected and analyzed.Compared with the IGS final products,the orbit accuracy of GPS satellites can reach cm-level.The orbit error in radial direction is minimum,which is about 2cm and the orbit error in tan- gential direction is maximum,which is about 8cm.And the clock precision of GPS satellites is better than 0.2ns.The conclu- sion that the GPS real-time service data can be used to do real-time precise point positioning is represented.