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Traditional acoustic and magnetic techniques for detecting underwater vehicles are becoming less reliable due to advances in underwater technology such as composite materials, miniaturized electronics, and more space efficient battery technologies. Optical remote sensing technologies, such as Light Detection and Ranging (LiDAR) systems, are promising alternatives due to their high measurement accuracy, independence of operating environments, and simple integration onto airborne platforms. However, the penetration depth of direct detection methods is limited by the strong attenuation of light by the water column. Detection techniques that rely on monitoring changes to the inherent optical properties (IOPs) and other remotely sensed properties of water are thus being considered. Effects of underwater vehicles on ocean properties such as salinity and temperature have been well studied, but a stronger understanding of their effect on IOPs and optical constituents of the ocean is required for these new detection techniques. In this paper, the authors develop a system to measure the effect of underwater turbulence equivalent to an inspection-class Remotely Operated Vehicle (ROV) on the IOPs and other physical properties of the water column. Measurements are taken in an indoor water tank, freshwater reservoir, coastal waters and oceanic waters. Four vertical thrusters are used as a turbulence generator. Four commercially available sensors monitor the changes in IOPs and optical constituents of water above the turbulence generator. Preliminary results are presented on the effect of underwater turbulence on the optical and ocean properties measured. We conclude that the turbulence was able to be detected via changes in the IOPs at a distance of 10m under most conditions, with caveats and qualifiers discussed.
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