Date Added: Aug 2009
In this paper, the authors investigate the multi-channel MAC problem in underwater acoustic sensor networks. To reduce hardware cost, only one acoustic transceiver is often preferred on every node. In a single-transceiver multichannel long-delay underwater network, new hidden terminal problems, namely multi-channel hidden terminal and long-delay hidden terminal (together with the traditional multi-hop hidden terminal problem, they refer to them as "Triple hidden terminal problems"), are identified and studied in this paper. Based on their findings, they propose a new MAC protocol, called CUMAC, for long delay multi-channel underwater sensor networks.