A Sparse Signal Representation-based Approach to Image Formation and Anisotropy Determination in Wide-Angle Radar (in Turkish)
Kush R. Varshney, Müjdat Çetin, John W. Fisher III, and Alan S. Willsky
Sparse Signal Representation, Anisotropy, radar, SAR,
We consider the problem of jointly forming images and determining anisotropy from wide-angle synthetic aperture radar (SAR) measurements. Conventional SAR image formation techniques assume isotropic scattering, which is not valid with wide-angle apertures. We present a method based on a sparse representation of aspect-dependent scattering with an overcomplete dictionary composed of elements with varying levels of angular persistence. Solved as an inverse problem, the result is a complex-valued, aspect-dependent response for each spatial location in a scene. Our formulation leads to an optimization problem for which we develop a tractable, graph-structured approximate algorithm. We present experimental results on realistic electromagnetic simulations demonstrating the effectiveness of the proposed approach.
SIU2007 - IEEE Conference on Signal Processing and Communications Applications, Eskisehir, Turkey, June 2007