2026/07/31 by Atınç Pırtı
Earth and Planetary Sciences · Engineering · Environmental Science · #Altimeter #Cryospheric studies and observations #GNSS positioning and interference #Galileo (satellite navigation) #Geostationary orbit #Geosynchronous orbit #Medium Earth orbit #Multipath propagation #Polar #Polar orbit #Satellite #Soil Moisture and Remote Sensing
paper · doi:10.1080/01490419.2026.2711295
crossref issued 2026/07/31 · crossref published 2026/07/31 · crossref published-online 2026/07/31 · openalex publication_date 2026/07/31 · crossref created 2026/07/31 · crossref deposited 2026/07/31 · crossref indexed 2026/07/31 · openalex created_date 2026/08/01 · openalex updated_date 2026/08/01
High-precision Global Navigation Satellite System (GNSS) observations in Antarctica play an important role in monitoring bedrock deformation, which comprises the viscoelastic response to past ice-load changes (Glacial Isostatic Adjustment, GIA) and the elastic response to present-day ice-mass change. Although multi-GNSS constellations are commonly evaluated collectively, the influence of constellation-specific orbital configurations and signal architectures under extreme polar conditions remains insufficiently characterized. Using observations from seven Antarctic IGS stations (PALM, SCTB, DUMG, CAS1, DAV1, MAW1, and SYOG) spanning 2019–2025, the performance of the Galileo and the BeiDou Navigation Satellite System (BDS) constellations was investigated with respect to orbital geometry, multipath behavior, inter-system bias (ISB) variability, and Precise Point Positioning (PPP) convergence characteristics. Polar skyplot analyses indicated that BDS geostationary (GEO) and inclined geosynchronous orbit (IGSO) satellites remain predominantly below 15° elevation at Antarctic latitudes, contributing disproportionately to low-elevation observation density and elevated multipath susceptibility. When GEO/IGSO observations were excluded, the BDS medium Earth orbit (MEO) sub-constellation exhibited positioning behavior broadly comparable to Galileo’s predominantly MEO-based architecture. During austral summer periods, Galileo E5 observations exhibited lower sensitivity to seasonal firn-related reflectivity changes compared to BDS B2a, consistent with the expected robustness of the wideband Alternative Binary Offset Carrier (AltBOC) modulation. Wintertime temperature minima below −50 °C were associated with seasonally varying ISB patterns exhibiting apparent lag behavior on the order of several weeks, although the underlying physical mechanisms require further investigation. Static PPP analyses further indicated that multi-GNSS solutions using GPS+GLONASS+Galileo + BDS-MEO achieved shorter median convergence times than standalone Galileo or BDS-ALL solutions under both geomagnetically quiet and elevated solar activity conditions. In addition, MEO-filtered multi-GNSS processing yielded lower vertical velocity uncertainties than BDS-ALL solutions. These findings suggest that constellation-aware processing strategies may improve positioning stability and velocity estimation performance for Antarctic GNSS applications relative to conventional all-in-view approaches.