The Role of LiDAR Data in Understanding the Relation Between Forest Structure and SAR Imagery

Abstract-As part of the 2000 PACRIM II Mission to Australia, polarimetric Synthetic Aperture Radar (SAR) data were acquired near Injune, central Queensland, Australia. The primary purpose of the acquisition was to better understand the role of SAR for retrieving biophysical properties of native forests through either empirical relationships or simulation modeling. In this paper, we outline the generation of a three-dimensional representation of the forest structure and component elements (leaves, branches and trunks) using field, airborne LiDAR and CASI data and aerial photography acquired at the same time as the AIRSAR. We then show how this representation formed the basis of the input to a coherent SAR imaging simulation that models microwave penetration and interaction with canopy and understorey components. A preliminary comparison between actual AIRSAR and simulated SAR data for a poplar box (Eucalyptus populnea) woodland suggests effective modelling of SAR backscatter