SAR Coregistration by Robust Selection of Extended Targets and Iterative Outlier Cancellation

• Published in: IEEE geoscience and remote sensing letters Vol. 19; pp. 1 - 5
• Main Authors: Pallotta, Luca, Giunta, Gaetano, Clemente, Carmine, Soraghan, John J.
• Format: Journal Article
• Language: English
• Published: Piscataway IEEE 2022; The Institute of Electrical and Electronics Engineers, Inc. (IEEE)
• Subjects: Azimuth; Constant false alarm rate (CFAR) detection; Correlation; Detectors; Iterative methods; Mean square error methods; Optimization; outlier cancellation; Outliers (statistics); Procedures; Radar imaging; Radar polarimetry; Robustness (mathematics); rotation and translation; SAR (radar); Synthetic aperture radar; synthetic aperture radar (SAR) coregistration; Trajectory; Zooming
• ISSN: 1545-598X; 1558-0571
• DOI: 10.1109/LGRS.2021.3132661

This letter extends the constrained least-squares (CLS) optimization method developed to coregister multitemporal synthetic aperture radar (SAR) images affected by a joint rotation effect and range/azimuth shifts enforcing the absence of zooming effects. To take advantage of the structural information extracted from the scene, the method starts with a detection stage that identifies extended targets/areas in the images. The selected tie-points allow the CLS problem to be reformulated to find its (initial) solution based on a robust subset of image blocks. Then, the mean square error (MSE) of each equation evaluated from the initial solution allows to implement an iterative cancellation procedure to further skim the CLS equation set. The effectiveness of the proposed procedure is validated on real SAR data in comparison with the standard CLS.