Abstract
Currently there are extensive modeling and measurement capabilities for the region extending from 100 ft above sea
surface to space, but few such capabilities exist for the region extending up to 10 ft above the sea surface. By measuring
and characterizing conditions in the marine boundary layer existing below 30 ft above the sea surface such as turbulence
and extinction, the optical communication capabilities of maritime vessels when operating at or near the surface may be
extended and enhanced. Key physical parameters such as absorption, scattering, and turbulence strength (Cn
2) along the
propagation path have a degree of variability on meteorological conditions as well optical wavelength. Modeling of the
atmospheric environment is thus critical in order to generate a good understanding of optical propagation through the
atmosphere. NUWC is utilizing software provided by MZA to model Cn
2 and resultant beam propagation characteristics
through the near-marine boundary layer. We are developing the capability of near-marine boundary layer atmospheric
and turbulence measurements and modeling as well as optical laser link testing at outdoor test sites. Measurements are
performed with optical laser links (e.g., bit rate error), scintillometer, and particle image velocimetry (PIV) cameras,
while turbulence and propagation modeling is achieved using MODTRAN5, ATMTools, NSLOT, LEEDR, and
WaveTrain modeling and simulation code. By better understanding the effects of turbulence on optical transmission in
the near-marine boundary layer through modeling and experimental measurements, measures can be implemented to
reduce the bit error rate and increase data throughput, enabling more efficient and accurate communication link
capabilities.
