摘要 |
An underwater communications network comprising a plurality of communication nodes operable to wirelessly communicate with at least one other node in the network, each node having a transceiver and an observation mechanism wherein the observation mechanism is operable to monitor signals received by the transceiver and upon reception of a first predetermined tone the observation mechanism outputs a signal operable to adjust the node from a passive operation mode to an active operation mode. Each node can be a discreet underwater device. |