Backscattering from capillary waves with application to sea clutter

The results of measurements at X -band of backscattering from water waves of amplitude less than about 0.01 wavelength and with wavelengths of the order of the microwave length are presented and compared with theory. The measurements have been made for both vertical and horizontal polarizations for grazing angles between 4\deg and 80\deg . The results both as to angular dependence and absolute magnitude are in agreement with the theory. The ratio of vertical to horizontal backscattering cross section calculated from the theory is compared with that measured on the open sea.