Improving Area Coverage With Mobile Nodes in Wireless Sensor Networks

Wireless sensor networks (WSN) consist of sensor nodes that detect relevant events in their vicinity and relay this information for further analysis. Considerable work has been done in the area of sensor node placement to ensure adequate coverage of the area of interest. However, in many applications it may not be possible to accurately place individual sensor nodes. In such cases, imprecise placement can result in regions, referred to as coverage holes, that are not monitored by any sensor node. The use of mobile nodes that can ‘visit' such uncovered regions after deployment has been proposed in the literature as an effective way to maintain adequate coverage. In this paper, the authors propose a novel integer linear programming (ILP) formulation that determines the paths the mobile node(s) should take to realize the specified level of coverage in the shortest time. The authors also present a heuristic algorithm that can be used for larger networks.