A distributed self-healing coverage hole detection and repair scheme for mobile wireless sensor networks

The most fundamental task of the wireless sensor network (WSN) is to monitor a specified region of interest with sufficient sensor coverage. This task is jeopardized when coverage holes appear after the network's deployment. The emergence of coverage holes is unavoidable for many reasons such as sensor node energy depletion, physical damage, or external attacks. Therefore, it is important to have an ongoing mechanism for coverage maintenance because coverage holes can have debilitating effects on network performance if left unattended. Existing research into coverage hole repair tend to suffer from several shortcomings such as high energy consumption of mobile nodes and inaccurate assumptions about the coverage hole model. Furthermore, many solutions rely on the availability of redundant nodes or deploying new nodes in the network, which is not always feasible. We present a novel distributed self-healing algorithm called distributed hole detection and repair (DHDR), that simultaneously handles both hole detection and repair using only nodes already deployed in the network. Our algorithm can dynamically detect a coverage hole as it occurs, and accurately estimate its position and size. The algorithm selects suitable nodes from the vicinity which will maximize coverage and minimize energy consumption by sharing information and coordinating their movements. The selected nodes relocate in a way that restores the void area of a hole without disrupting their existing coverage or connectivity. The performance of the proposed approach is evaluated through simulation experiments. It is compared against two state-of-the-art algorithms and has been shown to outperform both in terms of improved coverage, more stable connectivity, and lower energy consumption.