An efficient coverage hole-healing algorithm for area-coverage improvements in mobile sensor networks

Maximizing network coverage is among the key factors in designing efficient sensor-deployment algorithms for wireless sensor networks (WSNs). In this study, we consider a WSN in which mobile sensor nodes (SNs) are randomly deployed over a two-dimensional region with the existence of coverage holes due to the absence of any SNs. To improve the network coverage, we thus propose a novel distributed deployment algorithm – coverage hole-healing algorithm (CHHA) – to maximize the area coverage by healing the coverage holes such that the total SN moving distance is minimized. Once the network is formed after an initial random placement of the SNs, CHHA is applied to detect coverage holes, including hole-boundary SNs, based on computational geometry, i.e., Delaunay triangulation. The distributed deployment feature of CHHA applies a concept to virtual forces that is used to decide the movement of mobile SNs to heal the coverage holes. The simulation results show that our proposed algorithm is capable of exact detection of coverage holes in addition to area-coverage improvement by healing the holes. The results also demonstrate the effectiveness of CHHA compared with other competitive approaches, namely, VFA, VEDGE, and HEAL, in terms of total moving distance.