Research On The Model Of Ionospheric Delay Correction In GPS Precise Point Positioning

Precise Point Positioning (PPP) is a new GPS technique developed in the last few years, which is very useful for the orbit determination of LEO satellite, wide area geoscience research and national land resource investigation, aslo is the GPS of hot point research. In Precise Point Positioning,one of the major error sources is Ionospheric delay . however, as the ionosphere itself is unstable, with the current understanding of its physical characteristics are certain ambiguity, limited by the accuracy of their experience model to describe.In this paper is focus on ionospheric delay error on the single point positioning precision the impact of an in-depth study, the aim is to establish model of the ionosphere to the elimination of Precise Point Positioning the impact of the error. Several summed up the current ionospheric delay corrective models. Research details follow by:1. Study of the ionosphere and the fundamental characteristics of the ionosphere on single-point precision of GPS positioning measuring the impact. GPS in the research and application, the main model of the ionosphere, the existing model of the ionosphere delay in the analysis and discussion.2. Klobuchar model on the correct formula and calculation methods, the main single-frequency receiver for the ionospheric delay corrective.3. Focused on the dual-frequency observations measured ionospheric delay corrective establishment of the theory and model, using the double single base station frequency observations to establish a single station VTEC model, the last to eliminate Precise Point Positioning of error.4. Matlab-based platform based on the preparation of the establishment of ionospheric delay in the procedure error model, and its main realization of a single station Klobuchar model and surface fitting model building. Klobuchar will be calculated by the model and the single-station surface fitting model of the ionosphere correction, into a single point precision GPS positioning coordinates for the solution, and this solution results are compared and analyzed, and a further increase Single Station surface fitting model.