Terrain backscattering coefficient generator

Abstract

A generator for producing backscattering coefficient (/spl sigma//sup 0/) values for several terrain types under varying measurement conditions is developed. The types of terrain include soils and rocks, trees, grasses, shrubs, short vegetation, roads, urban areas, dry snow, and wet snow with measurements coming from the University of Michigan (Ulaby and Dobson, 1989). Measurement conditions are defined by 1) incidence angle (0/spl deg//spl les//spl theta//spl les/90/spl deg/), 2) transmitted and received wave polarizations (HH, RV, and W), and 3) radar band: L, C, S, X, Ka, Ku, and W. Furthermore, the /spl alpha//sup 0/ generator output statistics match the first and second moments of the measured data, as well as a large number of the frequency of occurrence histograms. Goodness-of-fit between generated and measured histograms was verified using a chi-square test at a 0.05 rejection level. An alternative validation test for grazing angles was implemented since the amount of available measured data was limited. In general, both tests failed to reject the proposed generator as representative of the measured data. The /spl alpha//sup 0/ generator provides a realistic simulation tool for terrain /spl alpha//sup 0/ since it portrays the terrain's true statistical nature.