Using WiMAX technology to improve volcano monitoring: the WEIRD System

, commonly known as WiMAX (Worldwide Interoperability for Microwave Access Forum), is one of the most promising broadband wireless access technology for next generation all-IP networks. This access technology allows reaching high bit rate and covering large areas with a single Base Station (BS). Thanks to these features, IEEE 802.16 opens the way for the use and the introduction of wireless technologies in particular emergency scenarios, like volcano monitoring. Active volcano surveillance is based prevalently on the analysis of geophysical and geochemical parameters gathered by monitoring networks. Of all, seismology is one of the most useful methods for volcano monitoring. In fact, several types of seismic signals, e.g. volcano-tectonic earthquakes (VT), long-period events (LP), volcanic tremor, can occur before and during an eruption. The analysis and interpretation of these seismic signals are a very important task for the volcanic eruption forecasting (Scarpa and Tilling, 1996). WiMAX technology can be applied to provide broadband wireless access in volcano monitoring scenarios, in order to solve all the problems that today limit the possibility to realize a real-time and accurate monitoring of volcanoes activities in emergency situations. In particular, this paper focus on a novel solution, designed within the IST FP6 EU WEIRD (WiMAX Extension to Isolated Research Data networks) Integrated Project, to perform volcano monitoring using the features offered by IEEE 802.16 networks in order to improve transmission of data acquired by temporary seismic stations deployed during emergencies. Tests performed on field demonstrate the advantages offered by the use of WiMAX compared with other commonly used technologies. 2.Volcano monitoring and WiMAX technology The permanent networks are fundamental to recognize a variation in the seismic behavior of an active volcano. Unlikely, in some circumstances, the data recorded only at the permanent networks are not enough to study in detail the spatial and temporal features of earthquakes preceding and accompanying eruptions. This is due either to the insufficient number of deployed seismic stations or to the instrument inadequacy (i.e. too few digital broadband equipments). When a volcano shows an increase of geophysical and geochemical background parameters, the Permanent Seismic Network is improved with temporary digital stations deployed as soon as possible to enhance both the network geometry and the quality of the recorded data. The temporary instruments are portable digital seismic stations generally equipped with broadband seismometers and characterized by continuous local recording on removable media (e.g. hard disk, magneto optical disk, compact flash). …