Scholarly record
INTEGRATION OF GNSS-DERIVED ROAD DATA AND DIGITAL TERRAIN MODELS FOR THREE-DIMENSIONAL SURFACE RECONSTRUCTION IN AN UNDEFINED HEIGHT SYSTEM
Abstract
Three-dimensional terrain reconstruction for applications such as geodetic modeling and spatial analysis remains challenging when GNSS-derived observations are sparse, distributed primarily along road networks, and referenced to a vertical reference system different from that of the available digital terrain models (DTMs). This study presents a methodology for integrating GNSS-derived road observations with raster-based terrain models to reconstruct continuous and geometrically consistent terrain surfaces while preserving relative terrain morphology. The proposed framework transforms GNSS-derived linear observations into a raster-compatible representation and reconstructs missing terrain regions using a directionally weighted nearest-neighbor (DWNN) interpolation approach. Unlike conventional nearest-neighbor (NN) and inverse distance weighting (IDW) interpolation, the proposed method incorporates neighboring observations in both cardinal and diagonal directions to improve spatial consistency and reduce interpolation artifacts. A coefficient-based terrain adaptation model is subsequently applied to transfer topographic characteristics from the reference DTM to the GNSS-derived height system. Evaluation based on relative height differences between randomly selected pixel-coordinate pairs from the reference DTM demonstrates that the proposed DWNN method improves terrain structure preservation compared to conventional interpolation approaches. The method reduced Root Mean Square Error (RMSE) by approximately 34% relative to both NN and IDW interpolation while producing more spatially coherent terrain reconstruction in unconstrained regions. The proposed methodology enables integration of heterogeneous datasets defined in different vertical reference systems while preserving terrain morphology consistency.
Publication details
References7
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