Sensitivity of C-band Synthetic Aperture RADAR to field-scale soil surface parameters.

摘要

This thesis investigates the sensitivity of polarimetric variables from C-band Synthetic Aperture RADAR to near-surface soil moisture (6 cm), micro-topographical surface roughness, and biomass cover, during pre/seed and post-harvest over agricultural fields. Variables examined include: the like-polarized and cross-polarized linear intensity channels; polarization ratios; the Total Power signal; the co-polarized phase difference and co-polarized complex correlation coefficient; Pedestal Height; extrema of the completely polarized and unpolarized components; extrema of the received power and scattered intensity; and the polarization coefficient of variation. Classification of scattering mechanisms with the Cloude-Pottier and Freeman-Durden decompositions are also examined. The empirical relationships between RADAR variables and surface parameters are first analyzed using data collected during field-validation campaigns. Secondly, RADAR imagery is integrated over the watershed scale to assess the operational discrimination of tillage practices with these polarimetric variables and decompositions. Overall results provide an enhanced theoretical understanding of these variables and decompositions for agricultural target retrievals and demonstrate promise for use in an agricultural monitoring scheme.