An Adaptive TDMA-based MAC Protocol for Underwater Acoustic Sensor Networks

TY - GEN

T1 - An Adaptive TDMA-based MAC Protocol for Underwater Acoustic Sensor Networks

AU - Gorma, Wael

AU - Mitchell, Paul Daniel

PY - 2019/10/1

Y1 - 2019/10/1

N2 - Acoustic propagation through water suffers from attenuation that increases with both signal frequency and transmission range, with time-varying long propagation delays. The power spectral density of underwater ambient noise also changes with frequency. As a result, the usable channel bandwidth is heavily constrained and Medium Access Control (MAC) protocol design for Underwater Acoustic Sensor Networks (UASNs) is challenging. Striking a balance between channel utilisation and network end-to-end delay is particularly difficult. The Combined Free/Demand Assignment Multiple Access (CFDAMA) protocol has been shown to effectively minimise end-to-end delay and maximise channel utilisation, but existing approaches are reliant on synchronisation which is hard to achieve underwater. This paper introduces a novel robust MAC protocol, based on CFDAMA, exclusively designed for UASNs and called CFDAMA-NoClock. It is capable of providing an adaptive MAC solution without the need for synchronisation amongst independent node clocks. The protocol demonstrates a high level of practicality and simplicity. Both analytical models and comprehensive event-driven simulation of several underwater scenarios show that CFDAMA-NoClock can offer excellent delay/utilisation performance under two distinct traffic types and with various network parameters selected based on practical UASN technologies.

AB - Acoustic propagation through water suffers from attenuation that increases with both signal frequency and transmission range, with time-varying long propagation delays. The power spectral density of underwater ambient noise also changes with frequency. As a result, the usable channel bandwidth is heavily constrained and Medium Access Control (MAC) protocol design for Underwater Acoustic Sensor Networks (UASNs) is challenging. Striking a balance between channel utilisation and network end-to-end delay is particularly difficult. The Combined Free/Demand Assignment Multiple Access (CFDAMA) protocol has been shown to effectively minimise end-to-end delay and maximise channel utilisation, but existing approaches are reliant on synchronisation which is hard to achieve underwater. This paper introduces a novel robust MAC protocol, based on CFDAMA, exclusively designed for UASNs and called CFDAMA-NoClock. It is capable of providing an adaptive MAC solution without the need for synchronisation amongst independent node clocks. The protocol demonstrates a high level of practicality and simplicity. Both analytical models and comprehensive event-driven simulation of several underwater scenarios show that CFDAMA-NoClock can offer excellent delay/utilisation performance under two distinct traffic types and with various network parameters selected based on practical UASN technologies.

U2 - 10.1145/3366486.3366549

DO - 10.1145/3366486.3366549

M3 - Conference contribution

SP - 1

EP - 8

BT - WUWNET'19: Proceedings of the International Conference on Underwater Networks & SystemsOctober 2019 Article No.: 22 Pages 1–8

PB - ACM

ER -