IGS超快星历对GPS近实时反演水汽精度的影响研究

Research on effects of IGS ultra-rapid ephemeris on near real-time GPS inversing the water vapor

将IGS发布的超快星历与最终星历中卫星的坐标及钟差进行对比,初步验证IGS超快星历的精度。在此基础上,以美国国家海洋和大气局ARM实验中GPS连续运行参考站一周的观测数据作为实验对象,利用Bernese软件分别使用IGS最终星历以及超快星历进行GPS反演大气水汽含量的数据解算,将得到的基线精度以及对流层延迟值进行对比,结果表明采用最终星历和超快星历得到的基线精度基本相同,但对流层延迟值相差较大,并且差值较大的时刻一般出现在超快星历的外推时刻,并随着外推时间的增加逐渐增大。为此,本文设计了滑动式动态星历选择方案,通过实验验证,该优化方案能有效的提高近实时对流层延迟解算精度,满足GPS近实时反演大气水汽的精度要求。

The accuracy of IGS ultra-rapid ephemeris was verified by comparing the final ephemeris and ultra-rapid ephemeris. To the problem of low accuracy of IGS ultra orbit, a method of slipping choosing ephemeris was present to apply it in real inversing water vapor by GPS based on the observation data within one week of GPS Continuously Operating Reference Stations （CORS） in ARM test from NOAA. The comparison with the results obtained from final orbit shows that the accuracy of water vapor can satisfy the requirements of real-time application of GPS inversing water vapor. By comparing with sounding balloon water vapor, a conclusion that GPS water vapor is consistent with sounding balloon water vapor and detecting water vapor by GPS is feasible was drawn.