2-Dimensional Regional Mapping of Ionospheric Total Electron Content Using Kriging Interpolation over the Philippines: Initial Results

Abstract

Total electron content (TEC) is an important parameter in studying the characteristics of the ionosphere of the Earth. By measuring the phase and group delays of the signals produced by Global Navigation Satellite System (GNSS) satellites, the slant TEC along the ray path can be measured. Assuming that the ionosphere is a thin shell, the point of intersection between the shell and the ray path is the ionospheric pierce point (IPP). The slant TEC at this point can be converted to the vertical TEC (VTEC). To produce continuous 2-dimensional TEC maps, a mapping method must be used based on the data that has been measured. While there are numerous methods to map TEC that are in used today, this study investigates the performance of Kriging interpolation over the Philippine region using the data from the Philippine Active Geodetic Network (PAGENet). To test the performance, the maps produced were compared to the Global Ionosphere Maps (GIMs) which are provided by the International GPS Service (IGS). The initial results show that the PAGENet maps have lower TEC values compared to GIMS with a mean difference of ~6 TECU with 12 UT having the highest difference.