Application of the method of determination of coordinates according to GNSS-observations with binding to the network of active reference stations
Authors:   Lviv Polytechnic National University, SAVCHUK S. , PRODANETS I. ,   Transcarpathian regional branch of SE “UKRDAGP”, FEDORCHUK A. ,   Lviv Polytechnic National University
Published: May 2022

One of the main tasks of geodesy is to determine coordinates with high accuracy using GNSS-observations. To perform such tasks in geodesy usually use the relative method of determining the coordinates in static mode. The technique of the relative method is based on determining the coordinates of an unknown point relative to a known one. The coordinates of the base point must be known, often precisely specified on the basis of the State Geodetic Networks. Static mode of observation is most often used to build geodetic networks, because it has the highest accuracy. In this study, the base points were active reference stations, the coordinates of which are set from the weekly combined solution of the GNSS-network. The purpose of the work is to investigate the accuracy of the application of the method of determining the coordinates according to GNSS-observations with reference to the network of active reference stations. Methodology. The data of GNSS-observations performed at the triangulation points of the State Geodetic Network and data of reference stations are used in the work. Based on these data, conditional GNSS-networks were formed for their processing in the software package, which consisted of three reference stations and one triangulation point. The data processing process assumed that the nearest reference stations were taken as a control point, the specified coordinates of which were recorded as control and set in the ETRS2000 system. The obtained sets of coordinates of the same points and stations were transformed into the USK2000 system. The accuracy of the coordinates determined in this way was analyzed on the basis of coordinate differences and their standard deviations. Differences for reference stations were determined relative to the refined weekly coordinates, and for triangulation points relative to the mean. Results. The obtained differences at the points of the state network are within 1–2 cm, acquiring both positive and negative values. The only exception is the fifth observation session, where the differences are 2–4 cm with a positive sign. At the KOVL reference station, the coordinate differences vary from –1.2 cm to +1.8 cm, and at the MEL2 station from 0 cm to 5.4 cm. Coordinate changes at triangulation points were estimated by standard deviations of 2.1 cm, 1.1 cm, and 1.9 cm for XYZ, respectively. The accuracy of all other coordinates of the reference stations is 0.3–1.6 cm, with an average range from –2.7 cm to +1 cm. Scientific novelty and practical significance. The paper shows the method of determining the coordinates in the system USK2000 according to GNSS-observations with reference to the network of active reference stations. The proposed technique allows the use of satellite methods to determine the coordinates in the state system USK2000 with an accuracy of 1–2 cm, as well as significantly speed up and speed up the process of field work.