Land deformation monitoring in mining area with PPP-AR

The mining area deformation monitoring theory and method using precise point positioning (PPP) ambiguity resolution (AR) were studied, and an ambiguity fixing model with satellite and receiver combination phase delay (CPD) was proposed for zero-differenced PPP ambiguity fixing and its corresponding formula derivation was given. The data processing results for 1 h at six IGS stations in China show that 93% of ambiguities can be fixed within 10 min and all ambiguities can be fixed within 15 min. After ambiguity fixing, the positioning accuracy is improved by more than 85% in the E and N directions, with absolute positioning accuracy reaching millimeter level, and it was improved by 70% in the U direction, reaching centimeter level; the proposed zero-differenced ambiguity fixing model can effectively improve the convergence rate and positioning accuracy in PPP. Data monitoring continuously conducted for half a year at four CORS stations of Shanxi China Coal Pingshuo Group validated the feasibility of using PPP in mining area deformation monitoring.