Land clutter and shadowing with consideration of propagation in coastal regions

The work reported represents an initial attempt to account for radar propagation effects on land clutter and shadowing near coastal regions. The authors demonstrate an optical ray-trace method in which the index of refraction is modified by topographical features in accordance with some relatively simple meteorological assumptions. Their objective is to develop a methodology for combining propagation and terrain effects, rather than to accurately model the coastal meteorology itself. They have been studying terrain effects on clutter and target shielding using a terrain data base known as DTED (Digital Terrain Elevation Data) published by the Defense Mapping Agency. The data base provides terrain elevations on a 100 m grid for much of the Earth´s land mass