BDS/GPS Multi-Baseline Relative Positioning for Deformation Monitoring

Abstract

The single-baseline solution (SBS) model has been widely adopted by the existing global navigation satellite system (GNSS) deformation monitoring systems due to its theoretical simplicity and ease of implementation. However, the SBS model neglects the mathematical correlation between baselines, and the accuracy and reliability can be degraded for baselines with long length, large height difference or frequent satellite signal occlusion. When monitoring large-area ground settlement or long-spanned linear objects such as bridges and railroads, multiple reference stations are frequently utilized, which can be exploited to improve the monitoring performance. Therefore, this paper evaluates the multi-baseline solution (MBS) model, and constrained-MBS (CMBS) model that has a prior constraint of the spatial-correlated tropospheric delay. The reliability and validity of the MBS model are verified using GPS/BDS datasets from ground settlement deformation monitoring with a baseline length of about 20 km and a height difference of about 200 m. Numerical results show that, compared with the SBS model, the MBS model can reduce the positioning standard deviation (STD) and root-mean-squared (RMS) errors by up to (47.4/51.3/66.2%) and (56.9/60.4/58.4%) in the north/east/up components, respectively. Moreover, the combined GPS/BDS positioning performance for the MBS model outperforms the GPS-only and BDS-only positioning models, with an average accuracy improvement of about 13.8 and 25.8%, with the highest accuracy improvement of about 41.6 and 43.8%, respectively. With the additional tropospheric delay constraint, the CMBS model improves the monitoring precision in the up direction by about 45.0%.

Editorial for Special Issue “Precise GNSS Positioning and Navigation: Methods, Challenges, and Applications”

“…Wang et al [1] evaluated both a multi-baseline solution (MBS) model and a constrained-MBS (CMBS) model that had prior constraints of the spatial-correlated tropospheric delay in deformation monitoring. The reliability and validity of the MBS model was verified using the GPS/BDS data set from ground-based settlement deformation monitoring, with a baseline length of about 20 km and a height difference of about 200 m. They reported that the MBS model reduced the positioning standard deviation (STD) and root-mean-squared (RMS) errors by up to (47.4/51.3/66.2%) and (56.9/60.4/58.4%) in the north/east/up components compared with the single-baseline solution (SBS) model, respectively.…”

Real‐time precise orbit determination for FY‐3C and FY‐3D based on BDS and GPS onboard observation

“…Until now, a total of 44 BDS satellites are in normal operation, containing 15 BDS-2 satellites (5 GEO satellites, 7 inclined geosynchronous orbit [IGSO] satellites and 3 mediumearth orbit [MEO] satellites) and 29 BDS-3 satellites (2 GEO satellites, 3 IGSO satellites and 24 MEO satellites). There has been abundant research based on BDS-2/3, such as deformation monitoring [13,14], atmospheric sounding [15,16] and precise point positioning-real-time kinematic (PPP-RTK) positioning [17],etc. However, the most aforementioned studies about BDS are based on ground-based observation data and LEO spaceborne GPS observation data, while less onboard BDS observation has been applied for real-time LEO POD.…”