Influence of breaking waves and whitecaps on characteristics of echo signal of airborne bathymetric lidar is investigated at strong winds. The model of echo signal, considering following factors is advanced: finite height of waves, random refraction of light by sea surface, free from foam and breaking waves, diffuse scattering of light on both sites of a surface with whitecaps on crests of waves. The account of finite height of waves is represented especially important at strong winds as in these conditions influence of whitecaps can appear essential. The relations are received, allowing estimating average delay and broadening of the signal. It is shown that whitecaps weak influence on average characteristics at wind speeds to 20 m/s. This influence appears essential in that case when measurement of a delay and, accordingly, definition of depth of a bottom or reflecting object is made by times of the first arrival of a backscattering signal from water.
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