Modeling of the probability distribution function of sea surface slopes in problems of radio wave scattering

We analyze limitations in the description of radio wave scattering, which employs models of the probability distribution function of sea surface slopes on the basis of the Gram–Charlier series. It is shown that such models allow one to describe the scattering of radio waves for the incidence angles which do not exceed 5°–6° in the case of weak winds, and for the incidence angles 21°– 25° if the wind velocity is equal to 10 m/s. The combined model of the probability distribution function of sea surface slopes is constructed, which corresponds to the Gram–Charlier model in the region of small slopes, and to the Gaussian distribution in the region of large slopes.