The Study On The Correction Model Of The Atmospheric Delay Error In The Network RTK

Network RTK technology is a kind of high precision positioning technology developed in the 1990s.It has widely used in the field of the GNSS because of its advantages,such as:wide coverage,low operation cost and high positioning accuracy.Now with the construction of the CORS system,it has been promoted.How to solve the ambiguity of the whole week,eliminate the error in the process of positioning,and improve the positioning accuracy are becoming hot topics of the scholars.In this paper,a detailed study is made on the influence of the maximum of the network RTK on the delay error of the atmosphere,the work mainly include:firstly,We conclude the status of domestic and foreign scholars about the tropospheric and the ionospheric delay error in the network RTK positioning system,as well as the construction of CORS system conditions.Secondly,this paper introduces and discusses the basic theory of the global navigation satellite system network RTK,including the undifferential observation equation of the network RTK,the ambiguity solution of the reference station,the nature of the error and the processing method.We analyze the effect of the interpolation algorithm,and provide the basis for the three-dimensional interpolation of the mobile station.In view of the atmospheric delay,this paper introduces the nature and time delay principle of the tropospheric and the ionospheric delay error,does a simple narrative about the classical correction models,and puts forward tropospheric delay error correction model and ionospheric delay error correction model for network RTK,by using the undifferential error interpolation model of rover zenith tropospheric delay error and ionosphere ionospheric delay error of three-dimensional interpolation.Finally,the experimental verification of the tropospheric and ionospheric delay error correction model is carried out by using the measured data of the CORS network.The corrected positioning accuracy of the mobile station can reach the centimeter level,which is sufficient to meet the requirements of the majority of users.