Applied Research of VTEC Polynomial Model based on CORS Signal in Ionospheric Delays

Ionospheric influence is one of the main factors that restrains high precision positioning of Continuously Operating Reference Stations (CORS). This paper analyses the Vertical Total Electron Content (VTEC) polynomial model, calculates the total electron content of ionospheric delays from eight CORS stations by subsection modeling, and uses a third order spline interpolation function to carry out the fitting analysis of VTEC curve. A certain relationship is concluded between the distribution of CORS stations and ionospheric delays, which can be more competent to reflect the variation of daily electron content and maintain the continuity and smoothness of the total electron content in space.