采用超快星历中实测钟差进行精密单点定位精度分析

Analyzing Precise Point Positioning Precision by Using the Measured Clock Difference in Ultrafast Ephemeris

超快星历是国际GNSS服务(IGS)发布的一种精密星历文件。它不仅含有精度不低于5cm的卫星轨道数据,而且包含了24h的实测钟差数据以及24h的预报钟差数据,其中实测钟差数据的精度约为0.15ns.实验结果表明:若采用超快星历中实测钟差进行精密单点定位,当观测数据观测时段为1h时,定位误差小于0.96m;当采用2h观测数据时,定位精度优于0.18m;若观测数据时间长度增加到4h,能进行不低于8cm的精密单点定位。

Ultrafast ephemeris is a precision ephemeris file International GNSS Service（Internati onal GNSS service,IGS）provided.It not only contains the satellite orbital data accuracy no less th an as 5cm,and contains measurement clock difference data at 24 hand forecast clock difference data at 24 h,in which the accuracy of the measured data clock difference of about 0.15 ns.A large number of experimental results show that if Precise Point Positioning using the measured clock dif ference in ultrafast ephemeris,when the length of observation data is 1h,it can decimeter level po sitioning.When using 2hobservational data,excellent positioning accuracy to 0.2 m.If the data observation time length add to 4h,you can centimeter precise point positioning.