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Improving Beidou Point Positioning with Geographic Data

The accuracy of BeiDou Navigation Satellite System (BDS) point positioning is hampered by the worse Position Dilution of Precision (PDOP) due to the orbit configuration of BDS. This article aims to employ the Terrain Height Aiding algorithm with geographic data (i.e., Digital Elevation Model, DEM) to improve BDS/GPS point positioning in the obstructed environments like urban canyons, open pits, and ravines etc. With the contribution of adding geographic data, the results demonstrated that the percent of elevation error correction was up to 90%. The GPS elevation error changed from 2.3022 to 0.1777, and the BDS elevation error changed from 2.9858 to 0.0725.