Analysis of Vertical Deformation with the Adaptive Fusion of GNSS and Leveling Elevation Variation

Global navigation satellite system(GNSS) and leveling are two important approaches to obtain the numerical vertical deformation. Due to different instruments, error models, data processing methods and other factors, systematic deviations exist between the results of elevation variation derived from the two approaches. Therefore, an adaptive fusion method of GNSS and leveling elevation variation is proposed. Firstly, the adaptive least-square configuration is used to establish the transition model for elevation variation between GNSS and leveling coincidence points. Then, we use the model to correct the elevation variation of other GNSS control points. Finally, the inverse distance weighting algorithm is used to establish the regional elevation change velocity grid model. The experiment takes the data of Shandong Provincial leveling network and GNSS control network as an example. The elevation change transition model is established by using 60 GNSS leveling points with relatively elevation changes to achieve effective fusion of GNSS and leveling elevation changes, which weakening the systematic deviation between GNSS geodetic height variation and normal height variation, and improving the reliability of regional elevation change analysis in Shandong Province.