Back scattering from the sea surface

Abstract

The available experimental data on back scattering from the sea surface ("sea clutter" ) are described, and discussed with reference to the physical processes involved. It is shown that the scattering elements of the surface are illuminated by a combination of direct end indirect fields, the latter being "reflected" by surface elements closer to the radar. At low angles, these interfere destructively, giving rise to the so-called "critical angle," polarization dependence, "spikiness," and steeper frequency dependence. A theory is developed in which the elemental scatterers are taken to be the small patches or "facets" of the sea surface. This theory is shown to give characteristics which are in general agreement with available experimental data.