Delay and Queue Aware Adaptive Scheduling- Based MAC Protocol for Underwater Acoustic Sensor Networks

This paper mainly investigates the application of underwater acoustic sensor networks (UASNs), which are characterized by large-scale, sparse distribution, and varying traffic loads. Since the underwater acoustic channel is known for limited bandwidth, time variation, and long propagation delays, the strategy to access the common communication medium is required to improve the performance of UASNs. This paper proposes a delay and queue aware adaptive scheduling-based medium access control (DQA-MAC) protocol for UASNs. It combines adaptive scheduling transmission, reduction of handshaking packets, and concurrent transmission with the propose of improving the performance of network throughput, shortening end-to-end delay, reducing average energy consumption, and enhancing the fairness of transmission. Data transmission time is scheduled based on the information of propagation delays and the number of data packets waiting in each node queue. Furthermore, the strategy of concurrent transmission is implemented to leverage the long propagation delays. At last, reducing the number of handshaking packets is achieved with the approach of exchanging information by specially designed packets frames. The simulation results show that the proposed protocol outperforms the related traditional protocols in networks with varying traffic loads.