Fault-tolerant topology with lifetime optimization for underwater wireless sensor networks

Recently, underwater wireless sensor networks were proposed to explore underwater environment for scientific, commercial and military purposes. However, the limited energy of nodes is a challenge for underwater wireless sensor networks. To prolong the lifetime of battery-limited underwater wireless sensor networks, in this paper, a fault-tolerant topology that can effectively extend the network lifetime is proposed. Initially, the influence of node residual energy and load on node lifetime is analysed. Later the lifetime model of underwater wireless sensor networks is established, and the value range of node load adjustment coefficient satisfying network lifetime is obtained. Finally, the scale-free fault-tolerant evolution model with network lifetime optimization is built based on node residual energy and load case. In addition, simulation experiments are performed to validate performances of the new topology generated by the evolution model built. The results show that the new topology structure can balance the energy consumption of the nodes and prolong the network lifetime effectively, and has good fault tolerance.