On Dual-Polarized SARs and the Stokes Parameters

Abstract:
The four-element Stokes vector captures all of the information inherent to the complex image data in response to quasi-monochromatic polarized illumination from a synthetic aperture radar (SAR). Stokes parameters provide unique quantitative tools for image interpretation that are essential in certain applications. Evaluation of the Stokes parameters requires knowledge of the (complex) cross-correlation between the two orthogonal receive channels of a dual-polarized SAR. Most so-called dual-polarized SAR systems provide only the like- and cross-product images, ignoring the complex cross-product, thus discarding potentially valuable information. Many dual-polarized SARs (and their associated processors) could be upgraded to provide Stokes parameter data products at marginal cost.