Tree-based coverage hole detection and healing method in wireless sensor networks

In wireless sensor networks, coverage is a fundamental issue affecting the quality of service. A coverage hole may appear anywhere in the area being monitored at any time because of many reasons. Thus, hole detection and healing have become major challenges towards achieving perfect coverage. This study provides a novel algorithm using trees and graph theory to detect and describe the existing holes in the region of interest. Simulation results show that the tree-based method can indicate the location, size, and shape of coverage holes accurately. Based on the results for hole detection, a tree-based healing method is also proposed. The method is divided into two phases, namely, hole dissection and optimal patch position determination. Results obtained from the experimental evaluation reveal that the proposed healing method can increase the coverage rate with only a few additional sensors compared to other related methods.