This paper proposes an efficient spectrum manage scheme to fulfill environment-friendly and spectrum-efficient communication for underwater cognitive acoustic networks (UCANs). Due to the frequency-dependent attenuation, the available communication frequencies in water are severely limited. Nevertheless, this precious resource is still underutilized. In this paper, the problem of multiple cognitive acoustic (CA) users sharing available channels and optimal power allocation in underwater acoustic networks are studied. It aims to provide efficient spectrum utilization for CA users while avoiding harmful interference with both natural acoustic systems, such as whale, dolphin, and artificial acoustic systems, like sonar users and other underwater acoustic networks.
Available online: https://ieeexplore.ieee.org/abstract/document/7043486