Determination of parameters affecting accuracy of GNSS velocities

In this study, the main factors affecting the velocities of GNSS points were investigated. In order to improve the accuracy of GNSS velocities, the most suitable number of campaigns, the time between the campaigns, the length of the measurement are investigated using 14 campaigns of GNSS data obtained from the 8 TUSAGA-Active stations. The data are grouped in different combinations of measurements and was evaluated with the GAMIT / GLOBK software. In addition, multiple regression analysis was performed in order to test the effect of the determined parameters, statistically. As a result of the analyzes carried out in different measurement groups, it was obtained that the relation between the measurement period and velocities accuracy was √t and the inverse ratio between the time period among campaigns and the velocity accuracy was 2. It is seen that the number of campaigns has an positive effect on the determination of errors such as in the measurement of antenna heights and fixing the antenna on the points. In the study, only the horizontal velocities and velocity accuracies were examined.