Feature-enhanced synthetic aperture radar image formation based on nonquadratic regularization

• Published in: IEEE transactions on image processing Vol. 10; no. 4; pp. 623 - 631
• Main Authors: Cetin, M., Karl, W.C.
• Format: Journal Article
• Language: English
• Published: New York, NY IEEE 01.04.2001; Institute of Electrical and Electronics Engineers; The Institute of Electrical and Electronics Engineers, Inc. (IEEE)
• Subjects: Applied sciences; Exact sciences and technology; Image processing; Image reconstruction; Image resolution; Information, signal and communications theory; Layout; Mathematical models; Radar imaging; Radar scattering; Reflectivity; Regularization; Scattering; Sidelobes; Signal processing; Spaceborne radar; Speckle; Synthetic aperture radar; Telecommunications and information theory; Tomography; Performance evaluation; Experimental result; Imaging; Regularization; Optimization; Synthetic aperture radar; Image reconstruction; Inverse problem
• ISSN: 1057-7149; 1941-0042
• DOI: 10.1109/83.913596

We develop a method for the formation of spotlight-mode synthetic aperture radar (SAR) images with enhanced features. The approach is based on a regularized reconstruction of the scattering field which combines a tomographic model of the SAR observation process with prior information regarding the nature of the features of interest. Compared to conventional SAR techniques, the method we propose produces images with increased resolution, reduced sidelobes, reduced speckle and easier-to-segment regions. Our technique effectively deals with the complex-valued, random-phase nature of the underlying SAR reflectivities. An efficient and robust numerical solution is achieved through extensions of half-quadratic regularization methods to the complex-valued SAR problem. We demonstrate the performance of the method on synthetic and real SAR scenes.