Millimeter wave backscatter from deciduous trees

Abstract

Measurements of the millimeter-wave backscatter from deciduous (leafed) trees are explained using a simple scattering model. The backscatter from individual leaves was measured in the laboratory and used to justify the use of an average leaf radar cross section when computing the normalized radar cross section (NRCS) of tree canopies. NRCS measurements of canopies show that the direction in which incident radiation impinges on the canopy is an important factor in characterizing radar backscatter. Comparisons of measured NRCS values demonstrate that planophil and erectophil trees can be distinguished based on their backscatter at 215 GHz.