Distinction of landslide by monitoring acceleration to autonomous node in wireless sensing network

For monitoring natural landslide disaster, wireless sensing node network is so effective system. The sensing node is constructed by some sensors (acceleration, soil moisture, GPS and so on), data processing unit (micro processor) and wireless communication unit. The network topology we have constructed is mesh type. In the system, at sensing landslide, the node will transport the information to host system through the node network by using wireless communication. Generally, in natural field, the landslide is sensed as the changing of acceleration. But, it is so difficult to distinguish the landslide obviously. The acceleration of the sensing node will change by not only the landslide disaster but also collision with several hard blocks like stones. This paper describes the distinction method of landslide disaster by using only the signal of acceleration sensor mounted in the sensing node. The method focuses the time transition of frequency distribution of the acceleration signal. Observing the time transition, the situations of sensing node have been distinguished.