Coverage holes reduction in movable sensor networks using Minimum Movement Technique

In wireless sensor networks, the efficiency mainly depends on the network connectivity among the nodes as well as coverage of the monitoring area. To handle the connectivity problem, the possible network partitions are detected earlier by detecting the cut-vertices which are the critical nodes in the network whose failure leads to network partition. These points are identified through Cut-vertex determination algorithm. The failure handler set, which is used to restore the connectivity failure due to failure of any cut-vertex, is determined by Connected Dominating Set (CDS) algorithm. The connectivity problem in the network is resolved by utilizing the controlled mobility feature of the sensor nodes. The coverage holes are introduced in the network due to the total movement of such failure handler set. To minimize the number of coverage holes, the failure handler is placed nearer to the position of failed node without affecting the connectivity. This technique is named as Minimum Movement Technique (MMT). To restore the connectivity, the nodes in the failure handling set move towards the feasible points. These points are calculated by MMT. The Simulation results prove that the proposed MMT minimizes the total mobility distance required to reach these points and the coverage holes in the network.