Connectivity Repair Heuristics for Stationary Wireless Sensor Networks

Wireless sensor network connectivity is a crucial parameter since it keeps the network operative. Network connectivity may be lost due to a variety of factors, such as energy depletion and sensor node failure. Therefore, the network will be partitioned into a set of disjoint sets, resulting in a loss of data collected by isolated sets. In this paper, we address the problem of connectivity repair for stationary sensor networks (WSNs) in case of multiple disjoint partitions. We propose two heuristics based on Dijkstra algorithm and minimum Steiner tree respectively, to deploy the minimum number of additional nodes while preserving the initial topology. For the two heuristics, a procedure is executed in the first stage to merge disjoint sets having a shared zone in their neighboring deployment zones to reduce the complexity of the solution. The first heuristic is adapted to free-obstacle areas and areas with few obstacles. It connects the less distant segments using Dijkstra algorithm. The second heuristic is rather appropriate for areas with opaque obstacles. Simulation experiments validate the effectiveness of the proposed methods compared to existing approaches.