On the Feasibility of Early Detection of Environmental Events through Wireless Sensor Networks and the Use of 802.15.4 and GPRS

JORGE SANTOS; RODRIGO SANTOS; JAVIER OROZCO

LECTURE NOTES IN COMPUTER SCIENCE

Springer

Año: 2009 p. 122 - 130

0302-9743

Wireless sensor networks, serving as the base of early warn-ing systems, have been extensively proposed to perform monitoring of weather and field variables in places of difficult access, trying to detect conditions leading to the beginning of damaging events and provide early warnings about them. Since the instant of sensing an anomalous condition, a relative deadline exists to take appropriate countermeasures. Therefore, the application is a paradigmatic real-time one. In this paper a general model of an Early Detection of Environmental Events System, following established technologies, based on the deployment of wireless sensor networks nodes and the use of the IEEE 802.15.4 and General Packet Radio Service, as the low and high ends communication networks respectively, is proposed. GPRS is used as backbone to link to a central computer the different grid squares served by 802.15.4. The computer operation is then described. In order to test its feasibility, the model is applied to the early detection of forest fires. The contribution of this paper is to show that although the system is theoretically apt to work well in grid squares of approximately 0.015 km2, its deployment in the totality of large areas, for instance National Parks of several thousands of km2, is unfeasible due to the sheer number of sensors necessary, and their present costs and deployment difficulties. Instead, a second best alternative, giving not an early warning of an impending fire but an early notice that the fire is in its beginning phase, something valued by professional fire-fighters, is shown to be feasible, from both technical and economic points of view.