Estimation Methods of VTEC Distribution Applied by Spherical Cap Harmonic Analysis and Kalman Filter

Abstract

In this paper, we present regional ionospheric delay models for global navigation satellite system (GNSS) and estimation methods of the ionospheric delay. The ionospheric delay models derived in this paper are based on the spherical cap harmonic analysis (SCHA). The SCHA coefficients are estimated by the least squares method and the Kalman filter and the ionospheric delay can be calculated from the estimated coefficients. In the experiments, the proposed models by the least squares method and the Kalman filter are compared with Klobuchar model. As a result, the effectiveness of the model estimated by Kalman filter is shown.