GPS星历精度对精密单点定位的影响

The influences of GPS ephemerises accuracy to the precise point positioning

精密单点定位的实质就是利用精密星历和精密卫星钟改正来实现单机精密定位。本文简要地介绍了精密单点定位的原理及技术关键,在此基础上,分析了IGS目前提供的3种精密星历(IGF、IGR、IGU)的精度和时延性。根据实验数据进一步分析了3种精密星历对精密单点定位精度的影响。通过精度分析,得出利用IGS的超快星历也可以达到厘米级定位精度,为全球厘米级单站RTK提供了有益的参考。

Using the precise ephemeris and the precise satellite clock correction can realize the precise point positioning （PPP） using a single receiver. This article introduces briefly the principle and the technical key of the precise point positioning. Then, accu- racies and latencies of three kind of precise ephemerises （IGF,IGR, IGU） provided currently by International GPS Service （IGS） are analyzed. This article has further analyzed influences of three kind of precise ephemerises to the precise point positioning accuracy according to the data. Through the accuracy analysis, we can draw a conclusion that a centimeter level of the pointing accuracy can be achieved by using the IGS ultra rapid ephemeris, which provides a reference to real-time kinematic precise point positioning.