Establishment of a new tropospheric delay correction model over China area  

作　　者：SONG ShuLi ZHU WenYao CHEN QinMing LIOU YueiAn 

机构地区：[1]Shanghai Astronomical Observatory, Chinese Academy of Sciences, Shanghai 200030, China [2]Center for Space and Remote Sensing Research, National Central University, Taiwan, China

出　　处：《Science China(Physics,Mechanics & Astronomy)》2011年第12期2271-2283,共13页中国科学：物理学、力学、天文学（英文版）

基　　金：supported by the National Natural Science Foundation of China (Grant No.10603011 and 41174023);the National High Technology Research and Development Program of China (Grant No.2009AA12Z307);Science and Technology Commission of Shanghai Municipality (Grant Nos.05QMX1462 and 08ZR1422400);the Youth Foundation of Knowledge Innovation Project of the Chinese Academy of Sciences;Shanghai Astronomical Observatory (Grant No.5120090304)

摘　　要：The tropospheric delay is one of the main error sources for radio navigation technologies and other ground-or space-based earth observation systems. In this paper, the spatial and temporal variations of the zenith tropospheric delay (ZTD), especially their dependence on altitude over China region, are analyzed using ECMWF (European Centre for Medium-Range Weather Forecast) pressure-level atmospheric data in 2004 and the ZTD series in 1999-2007 measured at 28 GPS stations from the Crustal Movement Observation Network of China (CMONC). A new tropospheric delay correction model (SHAO) is derived and a regional realization of this model for China region named SHAO-C is established. In SHAO-C model, ZTD is modeled directly by a cosine function together with an initial value and an amplitude at a reference height in each grid, and the variation of ZTD along altitude is fitted with a second-order polynomial. The coefficients of SHAO-C are generated using the meteorology data in China area and given at two degree latitude and longitude interval, featuring regional characteristics in order to facilitate a wide range of navigation and other surveying applications in and around China. Compared with the EGNOS (European Geostationary Navigation Overlay Service) model, which has been used globally and recommended by the European Union Wide Area Augmentation System, the ZTD prediction (in form of spatial and temporal projection) accuracy of the SHAO-C model is significantly improved over China region, especially at stations of higher altitudes. The reasons for the improvement are: (1) the reference altitude of SHAO-C parameters are given at the average height of each grid, and (2) more detailed description of complicated terrain variations in China is incorporated in the model. Therefore, the accumulated error at higher altitude can be reduced considerably. In contrast, the ZTD has to be calculated from the mean sea level with EGNOS and other models. Compared with the direct estimation of ZTD from the 28 GPS stations, the accurThe tropospheric delay is one of the main error sources for radio navigation technologies and other ground-or space-based earth observation systems. In this paper, the spatial and temporal variations of the zenith tropospheric delay （ZTD）, especially their dependence on altitude over China region, are analyzed using ECMWF （European Centre for Medium-Range Weather Forecast） pressure-level atmospheric data in 2004 and the ZTD series in 1999–2007 measured at 28 GPS stations from the Crustal Movement Observation Network of China （CMONC）. A new tropospheric delay correction model （SHAO） is derived and a regional realization of this model for China region named SHAO-C is established. In SHAO-C model, ZTD is modeled directly by a cosine function together with an initial value and an amplitude at a reference height in each grid, and the variation of ZTD along altitude is fitted with a second-order polynomial. The coefficients of SHAO-C are generated using the meteorology data in China area and given at two degree latitude and longitude interval, featuring regional characteristics in order to facilitate a wide range of navigation and other surveying applications in and around China. Compared with the EGNOS （European Geostationary Navigation Overlay Service） model, which has been used globally and recommended by the European Union Wide Area Augmentation System, the ZTD prediction （in form of spatial and temporal projection） accuracy of the SHAO-C model is significantly improved over China region, especially at stations of higher altitudes. The reasons for the improvement are： （1） the reference altitude of SHAO-C parameters are given at the average height of each grid, and （2） more detailed description of complicated terrain variations in China is incorporated in the model. Therefore, the accumulated error at higher altitude can be reduced considerably. In contrast, the ZTD has to be calculated from the mean sea level with EGNOS and other models. Compared with the direct estimation of ZTD

关 键 词：EGNOS GPS tropospheric delay SHAO-C model ECMWF pressure-level data 

分 类 号：P228.4[天文地球—大地测量学与测量工程] TS653.6[天文地球—测绘科学与技术]