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http://dx.doi.org/10.5515/KJKIEES.2018.29.5.366

Minimum-Entropy-Based Autofocus Method for Real SAR Images  

Hwang, Jeonghun (The 3rd Research and Development Institute, Agency for Defense Development)
Shin, Hyun-Ik (The 3rd Research and Development Institute, Agency for Defense Development)
Kim, Whan-Woo (Department of Electronics Engineering, Chungnam National University)
Publication Information
The Journal of Korean Institute of Electromagnetic Engineering and Science / v.29, no.5, 2018 , pp. 366-374 More about this Journal
Abstract
In cases of airborne equipped with SAR, because the occurrence of motion is inevitable, it is necessary to apply autofocus techniques to SAR images to improve the image performance degradations caused by residual errors. Herein, a robust autofocus algorithm based on the minimum entropy criteria is proposed for the real SAR data in the spotlight mode. The convergence condition of the phase error estimation is checked at every iteration and if it is violated, the size of the phase error estimation is adjusted to the convergence condition. The real SAR raw data is used to demonstrate the excellent performance of the proposed algorithm.
Keywords
SAR; Autofocus; Minimum Entropy; Phase Error;
Citations & Related Records
Times Cited By KSCI : 2  (Citation Analysis)
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