Three-dimensional X-band SAR imaging of a small conifer tree

High spatial resolution 3-D SAR imagery was recorded by the UK's Natural En vironment Research Council GB-SAR Microwave Measurement Facility at the Uni versity of Sheffield. X-band VV polarisation measurements were made using a near-field monostatic imaging system inside an anechoic chamber. The measu rement process employs vector network analyser techniques to sample backsca ttered signals over a 2-D aperture, allowing a 3-D reconstruction of a targ et. This technique is used to provide a detailed 3-D map of the spatial sca ttering behaviour of a small Colorado Blue Spruce tree (Picea pungens glauc a). The images produced are at a sufficiently high spatial resolution (simi lar to5 cm) that individual plant components can be discerned. An ability t o select any volume pixel from within the target allows features in the mic rowave reconstruction to be readily associated with structures in the tree. The scattering behaviour associated with the uppermost set of branches sho ws it to be dominated by scattering from the branch tips.