The GeoAlertNet©, is a wireless sensor network developed and adjusted for monitoring and early warning of landslides. The aim of the GeoAlertNet© is to collect geodetic data as well as geotechnical data. The data will be transferred by radio via the network to a base station. The communication and data interchange between user and base station can be carried out via one of the following: internet, satellite, GSM or UMTS. The GeoAlertNet© will work on low level energy consumption. For displacement measurements a high resolution ultrasonic distance measurement device for long distances has been developed. The distance measurement between two nodes work up to 25m and the accuracy of the determined displacement field will be in the range of cm. Typical geotechnical sensors can be connected to a sensor node via a so called PSoC. PSoC and sensor will be connected together to a plug-and-play unit, which can be added to an existing WSN, even if the WSN is in operation. A prototype of the GeoAlertNet© has been installed in Sept. 2009 in a landslide area nearby Engelberg, Central Switzerland.
In Switzerland approximately 7% of the total area is afflicted with landslide hazard (Raetzo & Lateltin, 2003). During the period 1972 to 2002 the portion of damage of traffic infrastructure due to landslides in Switzerland was 39%. At least 11% of damages on buildings have been generated by landslides. According to Schmid et al. (2004) landslides rank 2nd on the list of natural processes which cause damage in Switzerland. Those facts described above as well as the lack of an existing monitoring system which is able to collect both, geodetic and geotechnical data at the same time, have been the reason to develop a new monitoring system on the base of a wireless sensor network, the GeoAlertNet©.
