Dynamic Forward Hybrid Routing Algorithm by Small Node Group in Underwater Acoustic Communication

Underwater acoustic network plays an important role in various operations in the marine environment. It is very necessary to design a routing protocol that can adapt to the underwater environment with high time-varying and Doppler frequency shift. In this paper, we present a dynamic forward hybrid routing algorithm based on the small node group (SG-DFHR), to achieve a higher packet delivery ratio and lower energy consumption. The working process of SG-DFHR can be mainly divided into two stages. First, the randomly deployed underwater nodes are divided into several groups comprised of three nodes, which respectively serve as the master, secondary and ordinary node. Then a hybrid routing strategy is implemented for multi-hop transmission. In which, the master node uses the multicast for data packet transmission, while the rest nodes use the unicast method. Furthermore, in order to adapt to the dynamic changes of underwater network, we design a node group inspect and update strategy. The simulation and theoretical analysis show that our algorithm has superior performance over the ALRP, DCK-S-BEAR and SUN. Compared with the previous algorithms, under the premise of no significant increase in delay, the energy consumption and packet delivery performances of SG-DFHR are significantly improved. SG-DFHR achieves effective tradeoff among multiple performance metrics.