Laser propagation at 1.56 microm and 3.60 microm in maritime environments

We report results from field experiments that have compared laser propagation at 1.565 microm and 3.603 microm in a variety of atmospheric conditions in a low-altitude maritime environment in order to quantify the relative effects of turbulence under realistic conditions. Intensity scintillation and normalized focused spot sizes were found to be significantly less affected by turbulence at the longer wavelength, in general agreement with theoretical predictions. Also, the longer wavelength beam was noticeably less degraded by aberrations in the transceiver optical components. These advantages should be considered when evaluating the wavelength trade-offs in laser communication systems.