In the ground moving target indication with synthetic aperture radar (SAR) community, algorithms used to estimate the velocity of a detected moving target are important because they are relative to the topics about refocusing and azimuth displacement correction. The velocity is regarded as a vector with two components, one in azimuth and one in range direction, and new algorithms aiming at estimating the two components are proposed and verified. The range velocity estimator transforms a detected patch containing a moving target to range Doppler domain by using the 1-D fast Fourier Transform in each range bin to achieve its range Doppler locus. The slope of the range Doppler locus is computed by using the Radon Transform on the range Doppler plane and the range velocity component is worked out according to radar system parameters and the slope value. Two estimators are proposed to compute the azimuth velocity component. One is based on symmetric defocusing in Doppler domain, the other is based on phase gradient in wave-number domain. Experiments confirm the effectiveness of the estimators by using simulated and field data.
1. Raney, R. K., "Synthetic aperture imaging radar and moving targets," IEEE Transactions on Aerospace and Electronic Systems, Vol. AES-7, No. 3, 499-505, 1971. doi:10.1109/TAES.1971.310292
2. Barbarossa, S., "Detection and imaging of moving objects with synthetic aperture radar," IEE Proceedings F Radar and Signal Processing, Vol. 139, No. 1, 77-88, 1992.
3. Dias, J. and P. Marques, "Multiple moving targets detection and trajectory parameters estimation using a single SAR sensor," IEEE Transactions on Aerospace and Electronic Systems, Vol. 39, No. 2, 604-624, 2003. doi:10.1109/TAES.2003.1207269
4. Hinz, S., F. Meyer, A. Laika, and R. Bamler, Spaceborne traffic monitoring with dual channel synthetic aperture radar-theory and experiments, Proceedings of IEEE Computer Society Conference CVPR, Vol. 13, 57-65, San Diego, USA, 2005.
5. Weihing, D., S. Hinz, F. Meyer, A. Laika, and R. Bamler, "Detection of along-track ground moving targets in high resolution spaceborne SAR images," ISPRS Journal of Photogrammetry and Remote Sensing, Vol. 61, No. 3-4, 135-140, 2006. doi:10.1016/j.isprsjprs.2006.09.011
6. Hinz, S., F. Meyer, M. Eineder, and R. Bamler, "Traffic monitoring with spaceborne SAR-theory, simulations, and experiments," Computer Vision and Image Understanding, Vol. 106, No. 2-3, 231-244, 2007. doi:10.1016/j.cviu.2006.09.008
7. Chan, Y. K. and V. C. Koo, "An introduction to synthetic aperture radar (SAR)," Progress In Electromagnetics Research B, Vol. 2, 27-60, 2008. doi:10.2528/PIERB07110101
8. Baumgartner, S. V. and G. Krieger, "Acceleration-independent along-track velocity estimaiton of moving targets," IET --- Radar, Sonar and Navigation, Vol. 4, No. 3, 474-487, 2009. doi:10.1049/iet-rsn.2009.0030
9. Wong, S. K., "High range resolution profiles as motion-invariant features for moving ground targets identification in SAR-based automatic target recognition," IEEE Transactions on Aerospace and Electronic Systems, Vol. 45, No. 3, 1017-1039, 2009. doi:10.1109/TAES.2009.5259180
10. Chiu, S. and M. V. Dragoševic, "Moving target indication via Radarsat-II multichannel synthetic aperture radar processing," EURASIP Journal on Advances in Signal Processing, Vol. 2010, 1-19, Article ID 740130, 2010.
11. Baumgartner, S. V. and G. Krieger, "Real-time road traffic monitoring using a fast a priori knowledge based SAR-GMTI algorithm," Proceedings of IEEE IGARSS, Honolulu, USA, 2010.
12. Chang, C. Y., Y. L. Chiang, and K. S. Chen, "SAR image simulation with application to target recognition," Progress In Electromagnetics Research, Vol. 119, 35-57, 2011. doi:10.2528/PIER11061507
13. Koo, V. C., Y. K. Chan, G. Vetharatnam, M. Y. Hua, C. H. Lim, C.-S. Lim, C. C. Thum, T. S. Lim, Z. bin Ahmad, K. A. Mahmood, M. H. Bin Shahi, C. Y. Ang, W. Q. Tan, P. N. Tan, K. S. Yee, W. G. Cheaw, H. S. Boey, A. L. Choo, and B. C. Sew, "A new unmanned aerial vehicle synthetic aperture radar or environmental monitoring ," Progress In Electromagnetics Research, Vol. 122, 245-268, 2012. doi:10.2528/PIER11092604
14. Friedlander, B. and B. Porat, "VSAR: A high resolution radar system for ocean imaging," IEEE Transactions on Aerospace and Electronic Systems, Vol. 34, No. 3, 755-776, 1998. doi:10.1109/7.705884
15. Budillon, A., V. Pascazio, and G. Schirinzi, "Estimation of radial velocity of moving targets by along-track interferometric SAR systems," IEEE Geoscience and Remote Sensing Letters, Vol. 5, No. 3, 349-353, 2008. doi:10.1109/LGRS.2008.915937
16. Tian, B., D. Y. Zhu, and Z. D. Zhu, "A novel moving target detection approach for dual-channel sar system," Progress In Electromagnetics Research, Vol. 115, 191-206, 2011.
17. Fan, C. Y., X. T. Huang, T. Jin, J.-G. Yang, and D. X. An, "Novel pre-processing techniques for cohenrence improving in along-track dual-channel low frequency sar," Progress In Electromagnetics Research, Vol. 128, 171-193, 2012.
18. Gierull, C. H., "Ground moving target parameter estimation for two-channel SAR," IET --- Radar, Sonar and Navigation, Vol. 153, No. 3, 224-233, 2006. doi:10.1049/ip-rsn:20045094
19. Moreira, J. R. and W. Keydel, "A new MTI-SAR approach using the reflectivity displacement method," IEEE Transactions on Geoscience and Remote Sensing, Vol. 33, No. 5, 1238-1244, 1995. doi:10.1109/36.469488
20. Ender, J., "Detection and estimation of moving target signals by multichannel SAR," Proceedings of EUSAR, 411-417, Königswinter, Germany, 1996.
21. Kirsht, M., "Detection, velocity estimation and imaging of moving targets with single-channel SAR," Proceedings of EUSAR, 587-590, Friedrichshafen, Germany, 1998.
22. Kersten, P. R., R. W. Jansen, K. Luc, and T. L. Ainsorth, "Motion analysis in SAR images of unfocused objects using time-frequency methods," IEEE Geoscience and Remote Sensing Letters, Vol. 4, No. 4, 527-531, 2007. doi:10.1109/LGRS.2007.896318
23. Wang, J. F. and X. Z. Liu, "Velocity estimation of moving targets using SAR," Proceedings of IEEE IGARSS, Vancouver, Canada, 2011.
24. Marques, P. and J. Dias, "Velocity estimation of fast moving targets using a single SAR sensor," IEEE Transactions on Aerospace and Electronic Systems, Vol. 41, No. 1, 75-89, 2005. doi:10.1109/TAES.2005.1413748
25. Marques, P. and J. Dias, "Moving targets processing in SAR spatial domain," IEEE Transactions on Aerospace and Electronic Systems, Vol. 43, No. 3, 864-874, 2007. doi:10.1109/TAES.2007.4383579
26. Legg, J., A. Bolton, and D. Gray, "SAR moving target detection using non-uniform PRI," Proceedings of EUSAR, 423-426, Königswinter, Germany, 1996.
27. Rüegg, M., E. Meier, and D. Nüesch, "Capabilities of dual-frequency millimeter wave SAR with monopulse processing for ground moving target indication," IEEE Transactions on Geoscience and Remote Sensing, Vol. 45, No. 3, 539-553, 2007. doi:10.1109/TGRS.2006.888464
28. Brush, S., S. Lehner, T. Fritz, M. Soccorsi, A. Soloviev, and B. Schie, "Ship surveillance with TerraSAR-X," IEEE Transactions on Geoscience and Remote Sensing, Vol. 4, No. 3, 1092-1103, 2011. doi:10.1109/TGRS.2010.2071879
29. Fienup, J. R., "Detecting moving targets in SAR imagery by focusing," IEEE Transactions on Aerospace and Electronic Systems, Vol. 37, No. 3, 794-809, 2001. doi:10.1109/7.953237
30. Cumming, I. G. and S. Li, "Improved slope estimation for SAR Doppler ambiguity resolution," IEEE Transactions on Geoscience and Remote Sensing, Vol. 44, No. 3, 707-718, 2006. doi:10.1109/TGRS.2005.861925