滑动时间窗技术在地基GPS数据实时解算中的应用

滑动时间窗技术使用移动的时间窗定义参与解算的GPS(全球卫星定位系统)数据的起止时间,使得最新的观测数据得以加入实时的数据解算,获得最接近实况的观测结果。使用固定宽度的时间窗,可在保证模糊度解算精度的同时,占用最少的计算机资源。以2008年中国境内6个IGS(国际全球卫星定位服务局)测站全年数据为例,采用滑动时间窗技术,用不同的时间窗宽度计算各测站的逐时对流层参数,以CODE网站上公布的上述测站的逐日天顶总延迟(Zenith Total Delay,ZTD)作为标准值,分别统计其标准差,分析不同宽度的时间窗对ZTD解算精度的影响。结果表明,业务化的"地基GPS实时水汽反演系统"应用滑动时间窗技术,将时间窗宽度设定在8h左右,可以在获得高精度对流层参数的同时,满足业务的实时性需要。

Application of Sliding Timing Window Technology to GPS Data Processing

The Technology of Sliding Timing Window（TSTW）can define the starting and ending time of GPS data involved in data processing.Using TSTW,the latest observations can be added into the real-time data processing with more actual results.Using a timing window with fixed widths,the accuracy of ambiguity resolution can be guaranteed with the least occupation of computer resources.Using TSTW and getting observations from 6IGS（International GNSS Service）stations in China in 2008,the parameters for the troposphere at these 6stations are calculated.Using the daily Zenith Total Delay（ZTD）of the stations that posted on the website of CODE as normal values,the standard deviations are calculated, respectively,and the influences on the accuracy and the real-time properties of ZTD solution by timing windows with different widths are analyzed.The operational system of＂Ground-based GPS Real-time Water Vapor Retrieval＂using TSTW can gain the parameters in the troposphere with high-accuracy and meanwhile meet the real-time demands of operation.The best timing window width is about 8hours.