A system and method of calculating corrections to a navigation solution based on accurate data are provided. GNSS ephemeris, clock models and other navigation information are received from at least three GNSS satellites and pseudo-ranging to the GNSS satellites is performed. A PVT solution is resolved from the GNSS ephemeris, clock models, and other navigation information and the pseudo range measurements. The PVT solution includes a statistical measure. Differential GNSS data for calculating the corrections to the PVT solution is received and a corrected PVT solution is calculated based upon the differential GNSS data. The corrected PVT solution is compared to a region defined by the statistical measure and the corrected PVT solution is rejected when the corrected PVT solution is not within the region.