Centroid drift of laser beam propagation through a water surface with wave turbulence

For underwater optical wireless communication (UOWC), the influence of waves close to the water's surface cannot be ignored. We build an experimental system of UOWC in a laboratory environment, where two fans are employed to produce water waves to simulate the turbulent water surface. The propagation and scattering of the input light are experimentally investigated, which shows that the scattering depends on the intensity of the water surface wave as well as the depth of its turbulence. Although at the receiver the laser spots are random and chaotic, their centroid drifts present spatial dependence, which is then investigated from the statistical point of view. Such characteristics may provide guidance to the optimization of receiving, tracking, and aiming devices.