Observing mission Choosing the right GPS positioning method for a particular survey application is very interesting. It depends on the accuracy the user needs. This part is intended to offer some general guidelines that are used in our methodology. There are at least two ways to accomplish this task. Firstly, we can use a baseline between two known points.
Receivers occupy each station for a few minutes.
Secondly, we can use another method called the antenna swap. It requires that the two receivers are active and collecting data from at least four satellites during the operation. One receiver occupies a control point while another receiver occupies the first known point of the survey. In a few minutes of observation we switch the receivers. In our case of study, we used the first procedure.