Energy-Efficient and Traffic-Dispersive Event Contour Tracking in Multi-sink Wireless Sensor Networks

In this paper, we propose a distributed event contour tracking (DECT) algorithm for multi-sink wireless sensor networks. We focus on the convex-shaped area event, which has a large effect region and may trigger many sensors at the same time. An area event may change its shape or move with time. Wild animal migration, army march, gas diffusion and chemical pollution are typical examples of area events. DECT utilizes near optimal regular hexagonal-based deployment to achieve energy efficiency and to track the area event contour. It finds out all sensor nodes on the event contour and collects their reporting data for tracking the event. DECT takes advantage of multiple sinks to forward data; it divides the event contour into several segments in a distributed way, and nodes in every segment will select a specific sink for transmitting reporting data. So, data traffic is dispersed and the chance of congestion and the packet dropping rate are thus reduced. We also perform simulation experiments for DECT and compare the simulated results with related ones to show the advantages of DECT.