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A JSW-based cooperative transmission scheme for underwater acoustic networks

The design of the MAC protocols for underwater acoustic sensor networks (UASNs) poses significant challenges due to the characteristics of underwater acoustic channels such as limited bandwidth, high bit error rate and long propagation delay. While cooperative transmission renders diversity gain through relay nodes. In this paper, we investigate cooperative transmission techniques for UASNs by integrating the juggling-like stop-and-wait (JSW) transmission scheme into data transmission based on traditional reservation-based MAC protocols. Specifically, upon completion of channel reservation between a pair of nodes, the data transmission between the transmitter and the receiver is operated in the JSW manner; the receiver forwards the just correctly received packets to its own intended receiver immediately, which can be treated as an implicit ACK by the transmitter. By doing so, the transmitter can know whether a data packet has been correctly received while the receiver's intended receiver, which is one of the transmitter's hidden terminals and is required to keep silent in traditional reservation modes, can piggyback receive most of the data from the two-hop node, which remarkably enhances the UASN's transmission efficiency. Simulation results validate the superior performance of data transmission with our proposed cooperative transmission scheme compared to the classic one with non-cooperative transmission scheme.