Comparison of finite source and plane wave scattering from corrugated surfaces
Abstract
The choice of a plane wave to represent incident radiation in the analysis of scatter from corrugated surfaces was examined. The physical optics solution obtained for the scattered fields due to an incident plane wave was compared with the solution obtained when the incident radiation is produced by a source of finite size and finite distance from the surface. The two solutions are equivalent if the observer is in the far field of the scatterer and the distance from observer to scatterer is large compared to the radius of curvature at the scatter points, condition not easily satisfied with extended scatterers such as rough surfaces. In general, the two solutions have essential differences such as in the location of the scatter points and the dependence of the scattered fields on the surface properties. The implication of these differences to the definition of a meaningful radar cross section was examined.
 Publication:

NASA STI/Recon Technical Report N
 Pub Date:
 April 1977
 Bibcode:
 1977STIN...7725373L
 Keywords:

 Plane Waves;
 Radar Imagery;
 Radar Scattering;
 Surface Roughness;
 Corrugating;
 Incident Radiation;
 Mathematical Models;
 Radar Cross Sections;
 Remote Sensors;
 Communications and Radar