Adaptive MAC Scheme using Queue Information for Underwater Environmental Monitoring System

Underwater acoustic communication can be applied to many fields, such as oceanic data collection, undersea exploration, disaster prevention, underwater environmental monitoring, and tactical surveillance. Underwater environmental monitoring system is one of basic technologies in these application fields. Therefore, there is a growing need for researching underwater monitoring systems. Underwater communication systems should be designed differently from terrestrial wireless systems because of the special characteristics of the underwater environment, such as bandwidth limitations, multi-path propagation, padding, long end-to-end propagation delay, high bit error, temporary loss of connectivity, and limited battery power. In this paper, we considered the throughput and energy efficiency for constructing an underwater environmental monitoring system. Further, we aimed to transmit high-priority data first. The proposed MAC (Media Access Control) protocol gives transmission opportunities according to priority, and the number of transmissions is scheduled depending on the value of the data. In addition, we compared the performance of the proposed MAC protocol with the TDMA (Time Division Multiple Access) protocol based on numerical analysis.