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A two-scale model of rough surfaces is considered which permits theoretical interpretation of the features of very high frequency scattering from such surfaces (say, from a sea surface). The scattering snrface is a m e d to be a superposition of small-scale ripple and large waves (swell). Reflection from the latter may be considered by the Kirchhoff approximation. The spatial spectrum of corrugations is taken into consideration; the calculations based on this model help to give an explanation of the behavior of the scattered intensity as a function of the angle of incidence 4, and to establish which factors affect this dependence at various values of 9. Theoretically predicted dependence of the scattered intensity upon radio wavelength 1, depolarization of the scattered s i g n a l , and other features of the scattered radiation are in good agreement with the experimental data obtained from direct measurements.Frequency spectra of the backscattered s i 4 were also investigated (experimental measurements were carried out at wavelengths 3.2 cm, 10 cm, 50 cm, 1.5 m, and 4 m). Observed shifts of the central frequency agree with results of other authors (for the range of a=3 cm to 200 m).The measured values of the spectrmn width appeared approximately twice those theoretically calculated. This may be explained by the M uence of dissipative processes and of fluctuations of the skin-deep layer drift velocities. Space correlation of the backscattered signal was also investigated (both theoretically and experimentally). 50 percent decorrelation occurs at distances compared with dimensions of a wave slope.

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