WRUMAC: A Waiting-Resouce-Utilized MAC Protocol for Underwater Acoustic Sensor Network

Abstract

Because of specific characteristics of underwater acoustic channel, handshaking-based medium access control (MAC) protocols for the underwater acoustic sensor network (UASN) face with two problems, the efficiency problem and the transmission problem. In this paper, we propose a waiting-resource-utilized MAC (WRUMAC) protocol for the UASN, which is a handshaking-based scheme. In the proposed WRUMAC protocol, when a node receives a control packet, it should wait for a period, and then send a response packet. The waiting period is used to ensure that all the neighboring nodes of the transmitter have received the control packet, and then the potential collisions can be avoided. By introducing the waiting period, the transmission problem caused by the asynchronous packet transmission in the UASN with long propagation delay can be solved. Moreover, the waiting period of a pair of nodes is exploited by their neighboring nodes to transmit extra data packets. By introducing the extra data transmission, the efficiency problem caused by the idle resource waste in the UASN with long propagation delay can be solved. Simulation results show that the proposed WRUMAC protocol outperforms the traditional handshaking-based MAC protocol, in terms of a higher network throughput and a lower end-to-end delay.