SBAS-Aided GPS Positioning with an Extended Ionosphere Map at the Boundaries of WAAS Service Area

Space-based augmentation system (SBAS) provides correction information for improving the global navigation satellite (GNSS) positioning accuracy in real-time, which includes orbit/clock and ionospheric delay corrections. At SBAS service area boundaries, is not fully available to GNSS users only a partial available, mostly information. By using geospatial correlation property of ionosphere information, coverage can be extended by spatial extrapolation algorithm. This paper proposes extending biharmonic spline The wide (WAAS) map its error compared with GPS Klobuchar model. mean reduction at low latitude 52.3%. method conventional when set corrections are available. 44.8%, improvement significant latitude.