Variation of single-frequency GPS positioning errors at Taiwan based on Klobuchar ionosphere model

In this paper, ten year´s single-frequency pseudorange observations from one IGS GPS receiver at Taoyuan (121.1°E, 24.6°N), Taiwan, were used to analyze the relation of the positioning error to the changes of the solar activities. The receiver´s position at each epoch is obtained by solving the pseudorange equation set. Positioning error is defined as the difference between the position from the equation set and the position published by IGS. The Klobuchar model is used the correct the ionospheric range delay during the positioning solution. The results showed that during the high solar activity years the positioning error is larger than that during the low solar activity years. For the single-frequency GPS receiver, the ionospheric delay is the main error source, and the error of the single-frequency GPS receiver is mainly controlled by the solar activity.