High-Bandwidth Underwater Communications

There is increasing value in rapid data exchange with underwater sensors and systems for investigation of undersea phenomena, including oceanography and oil exploration. Both potential and limitations in high-bandwidth undersea communication through free-space optical and fiber optical, radio-frequency electromagnetic, and acoustic techniques is reviewed in this paper. The author discusses, in particular, environmental and hardware performance boundary attributes in a variety of undersea scenarios for free-space optical communications. There is the capability for data bandwidths approaching 10 to the 9th power bits per second under suitable environmental conditions to be provided by free-space optical approaches. A serious challenge to moderate and long range performance is posed by high-ambient light and turbid water conditions (primarily from downwelling sunlight).