C-MAC: A TDMA-Based MAC Protocol for Underwater Acoustic Sensor Networks

Different from terrestrial wireless networks that use radio channel, underwater networks utilize acoustic channel, which poses great research challenges in medium access control (MAC) protocol design due to its low available bandwidth and high propagation delay characteristics. In addition, the high bit-error, high transmission energy cost, and complex multi-path effects in underwater environment make it even harder. In this paper, a suitable MAC protocol, named C-MAC (cellular MAC) for underwater acoustic sensor networks (UWANs) is proposed. C-MAC is a TDMA-based MAC protocol, which divides networks into many cells. Each cell is distributed a time slot; nodes in a cell, can only transmit packets in the cellpsilas time slot. Experiments show the protocol can avoid collision, minimize the energy consumption, and increase the throughput efficiency.