Comparison of spherical harmonic and B spline models for the vertical total electron content

摘要: [1] Most of the geodetic ionosphere models describe electron density Earth's atmosphere by global maps vertical total content (VTEC) for fixed time intervals (e.g., 2 h) assuming a single-layer model and using spherical harmonic expansion up to specific degree n. However, it is well known that are not suited representing data heterogeneous quality. As consequence, gaps cannot be handled appropriately. In this paper we present different approach modeling VTEC generally depending on space defining 3-D system base functions as tensor products trigonometric B spline longitude two sets endpoint-interpolating latitude time, respectively. We compare with similar resolution show how influence accuracy even in areas good coverage.