Hierarchical localization algorithm for sustainable ocean health in large-scale underwater wireless sensor networks

Being an extensive part of marine study, underwater localization has fascinated widespread consideration in both civil and military. The underwater sensor network localization should differ from existing terrestrial and recent localization techniques, owing to catastrophic ocean conditions, large-scale networks, and node drift, even in a static environment, along with the pretense of adverse challenges. To address these technical difficulties, we propose a hierarchical localization approach with anchor and ordinary nodes localized in two phases. First, anchor nodes are localized with the help of surface buoys, drifted on the water. Second, we propose a threshold that originates from the midpoint of the deployed anchor nodes for ordinary node localization. The nature of the threshold in the proposed technique enables the localization of all nodes in a network by demonstrating that the anchor node can cover 100% of the area after the nodes are deployed. Simulation results show that the proposed scheme gains high energy efficiency and precision, as well as wide localization coverage, which helps in ocean sustainability. In addition, the proposed technique is implemented in the Aqua-sim toolkit of NS-2 for the validation of the simulation results.