In-network area estimation and localization in Wireless Sensor Networks

In many applications of Wireless Sensor Networks (WSN), a large number of sensor nodes are distributed over an area under investigation. The sensors collect ground data at definite time interval and forward it to the sink. In case of an event, it is often required to estimate the affected area and to identify the location of the event. Since, in WSN, communication is costlier than in-network computation in terms of energy, it is better if the area can be estimated in a distributed fashion on the way when sensed data are forwarded to the sink via multi hop paths. In this paper, a light-weight distributed algorithm is proposed to estimate the area as well as to locate its center. Each node requires only the knowledge of its own location and transmits a single packet per round. Simulation studies have been done to evaluate the performance. Comparison with two other algorithms proposed earlier for area computation without localization shows that our algorithm performs better in terms of accuracy of area estimation improving the error percentage from 15% to 2%. Besides area estimation, the proposed procedure also can locate the center of the affected area with less than 1% error.