Time-based adaptive collision-avoidance real-time MAC protocol for underwater acoustic sensor networks

With the development of marine exploration, underwater acoustic sensor networks (UASNs) are characterized by large-scale, high-flow loads. In addition, media access control (MAC) protocols have a significant impact on the performance of UASNs due to their limited bandwidth, time variation, and long-propagation delayed underwater acoustic channel characteristics. This paper proposes a time-based adaptive collision-avoidance real-time (ACART) MAC protocol that combines concurrent transmission, adaptive scheduling transmission, and variable time slots to improve network throughput and channel utilization. The strategy of concurrent transmission improves channel utilization by reducing the number of handshakes. Scheduling transmission avoids packet collisions. The approach of using variable time slots increases the flexibility of the network. The simulation results show that the network throughput outperforms traditional protocols in large-scale, high-traffic load networks.