Evaluation Of Real-Time Precise Point Positioning Technique Performance In Polar Regions Using IGS and NAVCAST GNSS SSR Correction Products

Abstract

In both Antarctic and Arctic regions, human activities for social and scientific purposes are increasing day by day, and studies are carried out for different purposes including mapping, glacial and coastal erosion monitoring, marine survey, remote sensing, tectonic climate change monitoring, atmospheric monitoring, mining, tourism, fisheries, biology, medicine and social sciences by different professional disciplines. Most of these studies require the use of robust and reliable real-time positioning system with high positioning accuracy in polar regions that play a key role in the future of the world. The Real-time Service (RTS) project introduced by IGS in 2013 has given real-time positioning a new dimension. The introduction of real-time correction products, in addition to the precise satellite orbit and clock information determined by the IGS observation network, has revealed the RT-PPP (or RTK-PPP) technique, which is a combination of RTK and PPP technique. The precise products that used in RT-PPP technique are calculated by mainly IGS and its Analysis Centers, and other organizations, formatted in the RTCM State Space Representation (SSR) standard, and broadcasted to user over the internet via NTRIP (The Networked Transport of RTCM via Internet Protocol). In this study, real-time data of NABG (11.85700 E; 78.94300 N) and SCTB (166.7580 E; 77.8490 S) reference stations, which are the closest IGS RTS network stations to the north and south poles, respectively, were used. The RT-PPP coordinates of each measurement epoch of both stations were calculated using SSR products produced by the CNES and Spaceopal NAVCAST under different satellite configurations through the measurement period of approximately 26.5 hours between 24/10/2022 12:00:00 UTC and 25/10/2022 14:30:00 UTC. The results of this study using PPP-WIZARD software revealed that the multi-GNSS RT-PPP solutions improved the solution accuracy and shortened the convergence time compared to GPS-only, GLONASS-only, and Galileo-only. In addition, the obtained results showed that the performance of the RT-PPP technique was strongly dependent on the SSR product used for the solution. As a result of all these findings, it has been seSen that it is possible to determine 3D position with the RT-PPP technique in the order of cm-dm level of accuracy depending on the SSR correction products used in the solution and the satellite configuration in the Antarctic and Arctic regions, which have very extreme atmospheric and geographic conditions. It is considered that this study will make a significant contribution to the limited studies in the literature on the usability of the RT-PPP method in the Polar regions.

Bilal Mutlu

Research Assistant

My research interests include satellite geodesy, and natural hazard monitoring with geosensors. For more detailed information you can take a look at the summary of my Msc Thesis.