ABSTRACT
The slogan “GPS/GLONASS satellite measurements” has become popular recently. Judging by news provided by the press, including Inside GNSS, one may get the impression that the GLONASS system is making its comeback and the number of active satellites in the system is steadily growing. This was the reason for an increase in our interest in the joint utilisation of both navigation systems in practice, especially after the correction of the Russian reference system with respect to the ITRF system with only a centimetre shift parameters (September 2007). What remains is the problem of differences in the time scale, but nothing seems to demonstrate that this is particularly significant. So, what is it we did in order to confirm the impact of observations of GLONASS satellites on the accuracy of GNSS positioning? We conducted an experiment for which we selected monthly data (September 2007) from the BOGO, BOGI, and JOZ2 stations (BOGO and BOGI are very close to each other while JOZ2 is at a distance of approximately 42 km). The observations were processed using Trimble Total Control software as the network of selected points is not vast. The network of vectors connecting the specified points was designated using two alternatives. The first only used GPS observations while the second applied both systems – GPS and GLONASS. The quantity and configuration of GLONASS satellites makes impossible the independent analysis of observations exclusively
from the GLONASS system. In spite of the placement of successive GLONASS system satellites in orbit, the number of active SVS has not changed as of this day. The Russian’s efforts are concentrated on replacing the old type satellites with new ones.
