Abstract
Video-SAR can produce sequential images at high frame rate, providing a continuous surveillance over a region of interest (ROI). To accelerate the speed of image processing, the whole circular path of Video-SAR is divided into several sub-apertures. However, due to the severe coupling of range and cross-range direction of the circular path, standard autofocus techniques as Phase Gradient Autofocus (PGA) fail since the direction of image blur changes for each sub-aperture image (sub-image). We have developed an algorithm for sub-aperture processing of Video-SAR that estimates the phase errors from strong scatters in the unfocused sub-image based on echo regeneration, regardless of the sub-aperture position. After phase compensation, more focused sub-images can be obtained before they are compiled into a SAR video. Thus the efficiency and utility of Video-SAR sub-aperture processing is retained, while image quality is not compromised due to platform motion errors.
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References
Gorham LRA, Moore LJ (2010) SAR image formation toolbox for MATLAB. In: SPIE algorithms synthetic aperture radar imagery. International Society for Optics and Photonics, pp 769906–769906
Yegulalp AF (1999) Fast backprojection algorithm for synthetic aperture radar. In: Radar conference, 1999. The record of the 1999 IEEE, pp 60–65
Gorham LA, Majumder UK, Buxa P et al (2006) Implementation and analysis of a fast backprojection algorithm. In: SPIE algorithms synthetic aperture radar imagery, defense and security symposium. International Society for Optics and Photonics, pp 62370G–62370G
Ponce O, Prats P, Rodriguez-Cassola M et al (2011) Processing of circular SAR trajectories with fast factorized back-projection. In: Geoscience and Remote Sensing Symposium, pp 3692–3695
Moses RL, Ash JN (2008) Recursive SAR imaging. In: Proceedings of the SPIE Algorithms Synthetic Aperture Radar Imagery, pp 69700P–69700P
Hawley RW, Garber WL (2011) Aperture weighting technique for video synthetic aperture radar. In: SPIE Defense, Security, and Sensing, pp 805107–805107
Wahl DE, Eichel PH, Ghiglia DC et al (1994) Phase gradient autofocus-a robust tool for high resolution SAR phase correction. In: IEEE Trans Aerosp Electron Syst, pp 827–835
Linnehan R, Miller J, Bishop E, Horndt V (2013) An autofocus technique for video-SAR. In: SPIE algorithms synthetic aperture radar imagery, SPIE defense, security, and sensing. International Society for Optics and Photonics, pp 874608–874608
Ash JN (2012) An autofocus method for backprojection imagery in synthetic aperture radar. Geosci Remote Sens Lett 9:104–108
Lin Y, Hong W, Tan WX, Wang YP, Wu YR (2011) A novel PGA technique for circular SAR based on echo regeneration. In: IEEE CIE international conference on vol 1. IEEE
Gotcha Volumetric SAR data set, Version 1.0 (2007) https://www.sdms.afrl.af.mil/DataSets/gotcha.index.php
Acknowledgments
This work is supported in part by the National Natural Science Foundation of China under Grants 61271287, 61371048, 61301265.
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Hu, R., Min, R. (2015). An Autofocus Technique for Sub-aperture Processing of Video-SAR. In: Mu, J., Liang, Q., Wang, W., Zhang, B., Pi, Y. (eds) The Proceedings of the Third International Conference on Communications, Signal Processing, and Systems. Lecture Notes in Electrical Engineering, vol 322. Springer, Cham. https://doi.org/10.1007/978-3-319-08991-1_27
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DOI: https://doi.org/10.1007/978-3-319-08991-1_27
Publisher Name: Springer, Cham
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