Polarimetric techniques for enhancing SAR imagery

This paper describes several techniques for enhancing fully polarimetric, high-resolution synthetic aperture radar (SAR) imagery. Image enhancement is viewed as a pre-processing step to prepare the SAR data for sophisticated detection, discrimination, and classification algorithms. The paper considers enhancement techniques that use polarimetric information in the imagery to achieve one or both of the following goals: (1) reduction of image speckle, and (2) improvement in target-to-clutter contrast. Three enhancement techniques are presented: the polarimetric whitening filter (PWF), the polarimetric enhancement filter (PEF), and the polarimetric matched filter (PMF). These polarimetric processing techniques are applied to actual SAR data gathered by the Lincoln Laboratory MMW airborne sensor. The resulting target and clutter statistics are compared for typical data sets at both 1ft by 1ft resolution and 1m by 1m resolution.