VTEC estimation with Taylor Series Expansion model using GPS data for low latitude region

Among various sources of Global Positioning System (GPS) errors, the ionosphere is the most predominant. The user positional accuracy can be improved by Satellite Based Augmentation System (SBAS) such as GPS Aided Geo Augmented Navigation System (GAGAN) of India. The ionospheric error also affects the accuracy of this system and degrades the systems´ performance. Hence, there is a necessity to estimate and model this error. In this paper, the local ionospheric model known as Taylor Series Expansion (TSE) model is considered for analysis. The Vertical TEC (VTEC) obtained due to TSE model is compared with the experimental GAGAN TEC network data. The results show that the maximum VTEC values due to disturbed day are more than the quiet day. In addition, the TSE model estimates compares well for quiet day than that of the disturbed day.