Displacement of Overlapping Sensors to Heal Coverage Holes in Wireless Sensor Networks

Providing a global coverage in wireless sensor networks with least possible numbers of sensor nodes has an important effect on the quality of a service and collection of information. Following a local approach, a set of nodes are first randomly distributed in the desired region, and then are moved or new nodes added iteratively until the existing holes are covered. In this study, a local approach is proposed, which improves an existing (tree-based) method for detecting coverage holes and adding new nodes. The advantage of the proposed approach is that the coverage holes are covered using the existing overlapping nodes as much as possible. It means, when a coverage hole is detected, the existing nodes with an overlapping coverage are detected and moved in order to cover the hole; new nodes are added only when required. The experimental results show the efficiency of the proposed method in terms of the number of nodes as well as the number of iterations and time complexity.