Self-Adaptive MAC and Routing Protocols for Mobile Underwater Acoustic Sensor Networks

Mobile underwater acoustic sensor networks have been widely used in marine data collection, pollution detection, disaster prediction, underwater target search and the other areas. Network protocols are aimed to enhance the reliability and the efficiency of the data transmission for these network applications. However, the mobility of underwater nodes introduces dynamic changes in the network topology, as well as new challenges to the design of underwater network protocols. In this paper, we propose routing and MAC protocols which can be adaptive to the physical channel environment and can be adjusted according to the network status. The proposed routing protocol can decrease redundant forwarding by adjusting the routing depth according to the acoustic environments, also utilizing the positions of underwater nodes. Furthermore, the proposed MAC protocol can reduce conflict by adjusting the delay time for sending packets based on real-time network monitoring. Simulations are performed to show the improvement of network performance on packet delivery rate, throughput, end-to-end delay, and energy efficiency etc. The proposed network protocols are also evaluated from a field experiment conducted in the South China Sea.