Wide-Angle SAR Image Formation with Migratory Scattering Centers and Regularization in Hough Space
Kush R. Varshney, Müjdat Çetin, John W. Fisher III, and Alan S. Willsky
SAR, Scattering Center, Hough Space, anisotropy, scatter
Wide-angle synthetic aperture radar imaging presents numerous challenges, but also opportunities to extract object-level information. We present a methodology using an overcomplete dictionary and sparsifying regularization to characterize anisotropy (aspect-dependent scattering amplitude), and migration (aspect dependent scattering center spatial location), into the image formation process. We also introduce regularization terms in the normal parameter space of the Hough transform that favor solutions with sparsity along a line and consequently parsimony in the representation of glint anisotropy. The characterization of scatterer migration directly gives information about size and shape of objects in the spatial domain and such information can also be inferred from the parsimonious representations we extract for glint-type scattering.