Abstract:Giving error analysis on three frequently used zenith tropospheric delay correction models, including the Hopfield, Saastamoninen and EGNOS models, combined with the errors of meteorological elements and station position, this study obtains the degree to which the errors affect the assessment value of ZTD. Then, achieving the three models by C++ language, selecting a series of IGS station at different latitudes and elevations, using meteorological data provided by IGS Analysis Center, combined with the time and space information of the station, this paper calculates the real ZTD. Compared with the IGS troposphere products, the estimation of quality of the three models is achieved. The results show, according to the meteorological data, Saastamoninen and Hopfield model could reflect the changes of tropospheric delay in a certain day accurately. The corrective precision of Saastamoninen model is slightly higher than that of Hopfield model. The EGNOS model does not need the measured meteorological data. Meanwhile, its RMS is less than 0.1 m, and can also meet the requirement of GNSS meter level localization accuracy.