Accuracy estimation of GNSS observations at a reference basis as a means of testing the measuring equipment of local geodynamic monitoring

The procedures of GNSS-equipment accuracy testing are considered in the aspect of the matter of predicting the earth’s crust movements and deformations when substantiating the geoecological safety of highly radioactive waste disposal in geological formations. For verification, the 1st category reference basis of the Federal Scientific-Technical Center for Geodesy, Cartography and Spatial Data Infrastructurе was used. The experiment was performed with a two-system GNSS equipment of the geodetic class. The session of simultaneous observations at the points of the reference basis lasted 4 hours. A special technique is proposed for assessing the contribution to the total error of each measuring equipment set. The technique is based on the well-known procedure of determining the basis lengths from linear measurements in all combinations using the least squares method. Estimates of the GNSS measurements accuracy for simultaneous observing two global navigation systems GLONASS and GPS are obtained. The root-mean-square error of the contribution to measuring the baseline vector length of one equipment set was 2,9 mm.