Artificial signals in GPS, GLONASS and Galileo series explained by the UPWr scientists!
Global Navigation Satellite Systems (GNSS) are widely used for the monitoring of phenomena occurring on the planet Earth. For this purpose, we usually use observations of changes in the position of ground receivers, determined by observations of navigation satellites. The American GNSS system, called Global Positioning System (GPS), plays a key role and is continuously used most often by users. However, the observed temporal changes in the coordinates of ground stations obtained using GPS observations are the resultant of real natural phenomena, anthropogenic processes, and systematic errors of the GPS system. This raises the question of how to separate the errors of the GPS technique from the changes we actually want to observe, such as station displacements caused by ocean tides?
more...