Research On Tropospheric Refractive Index Profile Detection By Single Base Station GNSS

The profile of the atmospheric refractive index varies with the altitude,including the three-dimensional data,is the basic data for evaluating the atmospheric refraction effect.At the same time,they are basic data for atmospheric science research and meteorological service research.Therefore,the study of atmospheric refractive index profiles for navigation,positioning and the atmospheric sciences are all of significance.In terms of navigation and positioning,it is possible to provide accurate tropospheric delay corrections for satellite navigation and positioning resolution and improve positioning resolution accuracy.In the field of atmospheric meteorology,it is helpful to realize the real-time or near-real-time detection of changes in the tropospheric atmospheric refractive index.Atmospheric observation data detection methods,in addition to the most widely used surface weather stations established on the surface of the earth for conventional surface weather observation,there are many remote sensing technologies,such as radio probe air balloons,weather satellites,microwave radar and so on.These detection technologies all have their own advantages,but they all have certain flaws,and they cannot meet current needs in terms of observation accuracy,space-time resolution,and observation conditions.With the rapid development of satellite technology,GNSS meteorology research has gradually developed.Compared with traditional detection methods,ground-based GNSS atmospheric detection methods have the advantages of all-weather,real-time detection and all-weather observation.The single station ground-based GNSS inversion detection method does not require a large amount of data as a support in the process of atmospheric refractive index detection,which helps to achieve real-time detection of atmospheric refractive index.Therefore,the theory system of single-site ground-based GNSS detection of atmospheric refractive index profile is studied and studied theoretically.The main research contents and work of this article are as follows:1.The process and method for inverting atmospheric meteorological parameters of ground-based GNSS surveys were studied,including ground-based GNSS meteorological inversion equations,process delay estimation models,single-station ground-based GNSS estimation tropospheric delays,and so on.2.The single-site ground GNSS inversion of atmospheric refractive index technology is studied.The inversion process is first to obtain the relevant basic information of the ground station through precise single point positioning technology,including the station location,and the ground station.Base atmospheric parameters,and tropospheric delay data.Then the single-site ground GNSS inversion of atmospheric refractive index technology was used to realize the atmospheric refractive index parameter inversion algorithm,and the atmospheric refractive index profile was obtained.3.The method of inverting the atmospheric refractive index profile of a single station ground GNSS is verified experimentally,and the experimental results are compared with the meteorological sounding data to verify the effectiveness of the algorithm.The experimental results show that when single-site ground GNSS is used to detect the atmospheric refractive index profile,the inversion accuracy of atmospheric refractive index dry term can reach about 1.3N,while the wet item inversion accuracy is 8 to 1ON,and further optimization processing is needed.4.The optimization method for inversion of atmospheric refractive index profile of single station ground GNSS is studied.The inversion equation of the atmospheric refractive index dry term is based on the boundary of the troposphere,and a segmented model is established.The accuracy of the inversion result of the optimized atmospheric refractive index dry term is impproved to within 1N.The inversion equation of the atmospheric refractive index wet item divides the top layer of the atmospheric water vapor dense layer and the top layer of the atmospheric vapor layer to establish a segmented model.The accuracy of the inversion result of the optimized atmospheric refractive index wet item is increased by about IN.