Test networks

In 1985, the network Turtmann was established, primarily to test and compare GPS satellite receivers as well as GPS positioning and analysis methods. Furthermore, this network is also suitable for testing other surveying instruments.
The network includes nine control points within an area of 5 x 6 km. Due to the relatively large height differences between the points, this is an optimal three-dimensional network. The regularly repeated observations carried out by swisstopo allow kinematic investigations of tectonic activities in this geologically interesting area.

Regularily by swisstopo planned repeated measurements allow statements about the tectonic behaviour (Kinematic) in this geologically interesting area.

The network Thun was established in 1988 for testing and calibrating electronic distance measuring instruments and for calibrating the GPS antenna offsets. It includes 11 control points aligned linearly over a distance of 100 m.

The terrain is ideally suited for such tests and meets the two criteria of a free horizon and an environment free of the multipathing effect. Because of the repeated terrestrial observations carried out on these points, the coordinates and height are known with a relative accuracy of approx. 0.1 mm (1 Sigma).