Investigation of the capability of multi-GNSS PPP-AR method in detecting permanent displacements

The traditional-precise point positioning (PPP) technique may provide a positioning as precise as the relative positioning technique in long-term observation durations. However, since it cannot provide high-precision positioning due to ambiguity problem in short-term observations, the interest in the PPP-AR (Ambiguity Resolution) technique has increased. The main purpose of this study is to investigate the performance of traditional-PPP and PPP-AR techniques for monitoring permanent displacements, considering different observation durations based on different satellite combinations. For this purpose, a displacement simulator that can move precisely in one direction and in the horizontal plane over a small distance was used. 6 different displacements were simulated, and all collected GNSS observations were evaluated with traditional-PPP, PPP-AR, and relative methods. Moreover, these methods were examined by considering the Global Positioning System (GPS), European Global Navigation Satellite System (Galileo), and GPS/Galileo satellite combinations. The findings clearly demonstrated the superiority of the PPP-AR technique outperformed the traditional-PPP technique in short-term observation durations and emphasize the contribution of multi-GNSS (Global Navigation Satellite System) combinations to both methods.