PUCRC: A PSO-Based Unequal Clustering Routing Protocol for Underwater Acoustic Cooperative Networks

The clustering-based routing protocol for underwater acoustic networks (UANs) in ocean Internet of Things (IoT) effectively optimizes network energy consumption and extends network lifespan. However, the traditional equal clustering method may lead to premature node failure due to heavy load, thereby degrading network performance. In this article, we propose a particle swarm optimization (PSO)-based unequal clustering routing protocol for the underwater acoustic cooperative networks (PUCRC) in ocean IoT. In the context of underwater acoustic cooperative networks, we consider factors, such as node energy, transmission energy consumption, and the number of isolated nodes during cluster head selection. We use PSO to select cluster heads that minimize transmission energy consumption and reduce the number of isolated nodes unable to reliably communicate with cluster heads. During the clustering stage, different competition radii are set for cluster heads. Noncluster heads join different clusters based on their competitive radius and distance to form an unequal cluster structure, balancing the energy consumption of each cluster head and preventing premature death of certain nodes. To better approximate real-world underwater acoustic channels, we enhance the cooperative communication model in traditional underwater acoustic cooperative network routing protocols by introducing the Ekman drift model to simulate dynamic marine environments for ocean IoT. Simulation results demonstrate that our proposed method effectively reduces network transmission energy consumption, mitigates isolated node generation, improves energy balance within clusters, and extends entire network lifecycle.