Research And Application Of Area Tropospheric Delay Model Using In Ground_Based GPS/Met

In recent years,with the application areas of global positioning system (GPS) are increasingly more and more widely, such as geodynamics, atmospheric physics, remote sensing, geological disasters, the user require more and more higher accuracy of GPS positioning, however, the impact of tropospheric delay limit the accuracy of GPS positioning to further increase.Completing the atmosphere models to further improve the measurement accuracy on the GPS elevation, while increasing the accuracy of GPS sensing vapor,has become the urgent problem in this area.Based on the knowledge of the troposphere, this paper researches and analysises the troposphere delay influence of the positioning accuracy of GPS and the ground-based GPS remote sensing water vapor:Analysis the theory and method of tropospheric delay correction,structure local atmosphere models, and use a variety of methods to validate the accuracy of local models, provide the basis for the improvement of the GPS positioning accuracy and the precision of ground-based GPS remote sensing water vapor.The main research contents of this paper are as follows:1. the basic principles of Ground-based GPS remote sensing Water vapor and its recent advances:Summarize the basic theory of ground-based GPS remote sensing precipitable water vapor. Describe the hierarchical structure of the atmosphere, the correction methods of atmospheric delay and several commonly used model of the atmosphere delay in the GPS data processing,Summarize the extraction methods of the precipitable water vapor, and analysis the associated error, in order to ensure the accuracy of the ground-based GPS remote sensing water vapor.2. Research the methods of the calculating the absolute zenith vapor PWV of the gegional ground-based GPS network in real time:Based on the in-depth analysis of the tide, mapping function, the ionosphere, etc. on the inversion accuracy of the Precipitable water vapor,precision remote sensing of precipitable water vapor real-time, and test its external fitting accuracy.3. GPS remote sensing slant water vapor:Summarize the calculation method and principle of the GPS slant water vapor, and research the influence of horizontal gradient of atmospheric to the zenith delay and slant wet delay, analysis the relationship between the horizontal gradient of the atmosphere and atmospheric changes, satellite elevation angle, while with the GAMIT software analysis the Influence of the atmospheric loading to the precipitable water vapor and slant water vapor, to lay the foundation for subsequent high-precision chromatography vapor.4 Using the Hong Kong CORS network data in 2009 and meteorological data, calculate the zenith total delay, zenith wet delay, zenith dry delay value of this area, by analyzing the relationship between the zenith delay and the various factors, fit out of the regional troposphere model with the weather data for the parameters, and test its precision, and then establish a real time experience model using the time as the parameter, compare the meteorological factors calculated with this model with the meteorological elements which is caculated using European real-time interpolation and the true value, obtained the conclusion of practical value.