A Multi-Redundancies Network RTK Atmospheric Errors Interpolation Method Based on Delaunay Triangulated Network

摘要

Routine Network Real-time Kinematic (NRTK) techniques always use triangle as the interpolation unit to solve the users' ambiguity and atmospheric effects. Because of the limitation of the calculating unit, the correction information based on virtual reference station (VRS) technique cannot fully use the information from all the reference stations, so that the users' RTK initialization speed and positioning accuracy would be seriously affected. In order to avoid the loss of observation information, two interpolation methods, MLIM for ionosphere and RELIM for troposphere, were proposed in the paper. Relying on the existing Delaunay Triangulated Network (DTN) structure, the optimal and suboptimal units were selected to increase the interpolation baselines number. Using the data from the Earth Scope Plate Boundary, our methods obtained more accurate interpolation accuracy by 3 times and 6 to 30 times higher for ionosphere and troposphere, respectively, compared with the traditional models. Besides, these two models can get more stable performance regardless the change of satellites elevation and the altitude differences among reference stations. In addition, we developed an alternative integrity monitoring method for rover station, with the interpolating monitoring precision of centimeter level. The proposed method is feasible to evaluate the actual integrity index and monitor the actual accuracy in the users' position.