GNSS observation data processing and analysis at Antarctic stations
Students Name: Petrukha Viktoriia Yuriivna
Qualification Level: magister
Speciality: Space Geodesy
Institute: Institute of Geodesy
Mode of Study: full
Academic Year: 2022-2023 н.р.
Language of Defence: ukrainian
Abstract: Recently, in global navigation satellite systems (GNSS), the method of high-precision determination of coordinates in the absolute mode of PPP (Precise Point Positioning) has been actively developed. A feature of PPP technology is the use of external GNSS products, as well as detailed modeling of various types of errors, geophysical processes when observed by only one GNSS receiver. The accuracy of GNSS products is of a global nature and depends little on the physical and geographical features of one or another region, so it is obvious that the process of modeling errors arising under the influence of various factors of geophysical origin can have an ambiguous impact in different regions, especially, this may apply to Antarctica . On this continent, due to its specific conditions, there is a rather small number of GNSS stations, and therefore the processing and analysis of GNSS observations using the RRR method is an important scientific and applied task. The purpose of this work is to process GNSS observations at the Antarctic GNSS station ASAV using the PRR technology, as well as to compare its accuracy with the help of different software implementations. The work consists of five sections. First, general information about GNSS systems, basic equations of GNSS observations, errors that arise when processing these GNSS data, as well as processing strategies are considered. The next section contains a description of the exact positioning of the PRR point, methods for eliminating the ambiguity of the PRR, the evolution of the models of this method, and the software implementation of the PRR-AR technology. First, ASAV station data were prepared in the independent RINEX 3.04 format. Then, using the software package GipsyX and PRIDE PPP-AR, the coordinates of the ASAV station for the year 2021 were calculated. The performed calculations and the use of various functions of the PRIDE PPP-AR program made it possible to develop various strategies for processing multi-system observations. The research was focused on obtaining time series of coordinates, rates of change of coordinates and evaluating the capabilities of individual software packages. In particular, we compared the results of processing the coordinates of the ASAV station (from two software packages) with the corresponding data of the permanent IGS station PALM. Based on the comparison, conclusions are drawn. The object of the study is the Ukrainian permanent GNSS station ASAV. The subject of research is RRR technology and its implementation for Antarctic stations. Keywords: Global Navigation Satellite System (GNSS), multi-GNSS, PPP, time series of coordinates, rates of change of coordinates.