A pre-scheduling-based MAC protocol for underwater acoustic sensor network

Because of specific characteristics of underwater acoustic channel and real acoustic modems, it is challenging to design an appropriate medium access control (MAC) protocol for the underwater acoustic sensor network (UWASN). In this paper, we propose a pre-scheduling-based MAC protocol for the UWASN. In our proposed MAC protocol, the nodes with data packets to be transmitted reserve the channel in the reservation phase. According to the pre-scheduled receiving time of the reservation packets, the nodes with date packets to be transmitted can adjust the time instant of the transmission of control packets. Moreover, the spatial-temporal uncertainty problem is also considered so that the collision problem of control packets is resolved well. In the data transmission phase, the nodes with reserved channel transmit their data packets in a given order. Numerical results show that our proposed pre-scheduling-based MAC protocol performs well, and achieves the collision-avoid communication.