Rough surface scattering models

The Brown & Miller model for the coherent component of rough surface forward scattering is based on a hat surface geometric optics argument and is unable to account for shadowing effects at low grazing or the weakened nulls observed in experiments. This paper develops modifications to the coherent component of rough ocean forward scattering to account for (1) shadowing for downwind wave conditions, and (2) null weakening in the crosswind wave conditions. The downwind model modification accounts for shadowing by calculating the interference pattern referenced to the height above the mean illuminated and viewable sea surface. Similarly, the crosswind model modification accounts null weakening by averaging the interference pattern due to the vertical undulations of the ocean surface. The Brown & Miller model and proposed models are compared against experimental data (X-band, H-polarization) from a forward scattering measurement at low grazing