Free space optical communication (FSOC) links in the maritime environment have been demonstrated in ship-to-ship and ship-to-shore tests. FSOC over water is attractive because of long lines of sight and more stable turbulence conditions. Link performance, range, and availability depend on terminal design, visibility, and turbulence conditions. However, the ability to predict turbulence conditions and their effect on link performance is still an open question. Turbulence introduces an effective scintillation loss into the link that depends on turbulence, the desired quality of service and the design of the communication protocol. In this work we show that this loss can be calculated if the distribution function for scintillation is known. We use experimental measurements from the Naval Research Laboratory’s Chesapeake Bay Lasercom Testbed and both extended Rytov theory, and wave optics simulation to find predictive models for scintillation loss that use only environmental and system parameters as inputs.
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