CM-MAC: A Cluster-Based Hierarchical Scheduling Protocol for Reliable Neighborhood Multicasting in Mobile AUV Swarms

Abstract

Deploying Autonomous Underwater Vehicle (AUV) swarms is pivotal for oceanographic exploration. However, swarm formation control is constrained by harsh Underwater Acoustic Communication Networks (UACNs), especially in dynamic, non-fully connected topologies. To address high packet collision rates and excessive signaling overhead in existing Medium Access Control (MAC) protocols, this paper proposes a novel Cluster-based Mobile MAC (CM-MAC) protocol for hierarchical clustered AUV networks. Operating under a decentralized three-tier architecture, the protocol coordinates transmissions using local state information. We establish transmission constraints to prevent packet collisions among mobile nodes. Building upon the transmission constraints, genetic algorithms are applied to the transmission scheduling across all layers to optimize the sending sequence and timing, reducing overall latency. Simulation results show that the CM-MAC protocol significantly improves network throughput and reduces information-sharing update intervals when compared to traditional TDMA, pure Aloha, and random-access CM-MAC. This study presents a robust communication framework for coordinating large-scale AUV swarms in complex underwater environments.