This paper describes a convenient technique of precise radial velocity estimation for inverse synthetic aperture radar (ISAR). In order to keep both the range profile and phase history of the echoes coherent, direct sampling with high sampling rate using high performance analog-to-digital converter and matched-filter correlation processing in pulse compression are used for the ISAR system. Due to the coherence property of the echoes, the translational motion compensation parameters for ISAR imaging are just the radial motion parameters of the target. Thus, the coarse velocity estimation is obtained by range alignment and fine velocity estimation is achieved by phase adjustment. The fine velocity estimation is ambiguous and the coarse velocity estimation is used for ambiguity resolution. The advantage of this technique is the high precision with range error values at sub wavelength levels, and it achieves velocity information and translational motion compensation at the same time. Both simulated and experimental validations are presented to verify the effectiveness of the proposed method.
2. Liu, Y., S. Zhang, D. Zhu, and X. Li, "A novel speed compensation method for ISAR imaging with low SNR," Sensors, Vol. 2015, No. 15, 18402-18415, Jul. 2015.
3. Camp, W. W., J. T. Mayhan, and R. M. O’Donnell, "Wideband radar for ballistic missile defense and Range-Doppler imaging for satellites," Lincoln Laboratory Journal, Vol. 12, No. 2, 267-280, Feb. 2000.
4. Delaney, W. P. and W. W. Ward, "Radar development at Lincoln Laboratory: An overview of the first fifty years," Lincoln Laboratory Journal, Vol. 12, No. 2, 147-166, Feb. 2000.
5. Steudel, F., "An improved process for Phase-Derived-Range measurements,", World Intellectual Property Organization Patent, WO 2005 017 553A1, Feb. 24, 2005.
6. Steudel, F., "Process for Phase-Derived-Range measurements,", U.S. Patent 2005 030 222A1, Feb. 10, 2005.
7. Cao, Y., X. Qu, and P. Huang, "Accurate-velocity-measurement method for wideband radar based on keystone transform," Systems Engineering and Electronics, Vol. 31, No. 1, 1-4, Jan. 2009.
8. Liu, H. and J. Lu, "Target motion compensation algorithm based on keystone transform for wideband pulse Doppler radar," Transactions of Beijing Institute of Technology, Vol. 32, No. 6, 625-630, Jun. 2012.
9. Li, Y., M. Xing, J. Su, Y. Quan, and Z. Bao, "A New algorithm of ISAR imaging for maneuvering targets with low SNR," IEEE Transactions on Aerospace and Electronic Systems, Vol. 49, No. 1, 543-557, Jan. 2013.
10. Liu, Y., H. Meng, G. Li, and X. Wang, "Velocity estimation and range shift compensation for high range resolution profiling in stepped-frequency radar," IEEE Geoscience and Remote Sensing Letters, Vol. 7, No. 4, 791-795, Oct. 2010.
11. Berizzi, F., et al., "A contrast-based algorithm for synthetic range profile motion compensation," IEEE Transactions on Geoscience and Remote Sensing, Vol. 46, No. 10, 3053-3062, Oct. 2008.
12. Liu, Y., D. Zhu, X. Li, and Z. Zhuang, "Micromotion characteristic acquisition based on wideband radar phase," IEEE Transactions on Geoscience and Remote Sensing, Vol. 52, No. 6, 3650-3657, Jun. 2014.
13. Zhu, D., Y. Liu, K. Huo, and X. Li, "A novel high-precision phase-derived-range method for direct sampling LFM radar," IEEE Transactions on Geoscience and Remote Sensing, Vol. 54, No. 2, 1131-1141, Feb. 2016.
14. Song, P., H. Meng, T. Huang, and Y. Liu, "A novel target motion compensation method for randomized stepped frequency ISAR," 2013 Asilomar Conference on Signals, Systems and Computers, 917-921, Pacific Grove, CA, Nov. 3-6, 2013.
15. Mohapatra, B. B., S. Rajagopal, and V. A. Abid Hussain, "Translational motion estimation and compensation in inverse synthetic aperture radar," 2014 IEEE International Conference on Electronics, Computing and Communication Technologies, 1-5, Bangalore, Jan. 6-7, 2014.
16. Kathree, U., W. Nel, V. J. van Rensburg, and A. K. Mishra, "Investigation of hopped frequency waveforms for range and velocity measurements of radar targets," 2015 IEEE Radar Conference, 475-480, Johannesburg, Oct. 27-30, 2015.
17. Bucciarelli, M., D. Pastina, B. Errasti-Alcala, and P. Braca, "Translational velocity estimation by means of bistatic ISAR techniques," 2015 IEEE International Geoscience and Remote Sensing Symposium, 1921-1924, Milan, Jul. 26-31, 2015.
18. Brisken, S. and J. G. Worms, "ISAR motion parameter estimation via multilateration," 2011 Microwaves, Radar and Remote Sensing Symposium, 190-194, Kiev, Ukraine, Aug. 25-27, 2011.
19. Corretja, V., E. Grivel, Y. Berthoumieu, J. M. Quellec, T. Sfez, and S. Kemkemian, "Target radial velocity estimation robust against additive disturbances for ISAR application," 2011 IEEE CIE International Conference on Radar, 670-673, Chengdu, China, Oct. 24-27, 2011.
20. Berger, T. and S. E. Hamran, "An efficient scaled maximum likelihood algorithm for translational motion estimation in ISAR imaging," 2010 IEEE Radar Conference, 75-80, Washington, DC, May 10-14, 2010.
21. Aprile, A., D. Meledandri, T. M. Pellizzeri, and A. Mauri, "A new approach for estimation and compensation of target translational motion in ISAR imaging," 2008 IEEE Radar Conference, 1-6, Rome, May 26-30, 2008.
22. Lin, Q., B. Yuan, Y. Zhang, and Z. Chen, "Design and implementation of IF signal highspeed acquisition and real-time storage system for wideband radar," 2011 International Conference on Mechatronic Science, Electric Engineering and Computer, 2022-2026, Jilin, China, Aug. 19-22, 2011.
23. Lin, Q., Z. Chen, Y. Zhang, and J. Lin, "Coherent phase compensation method based on direct IF sampling in wideband radar," Progress In Electromagnetics Research, Vol. 136, 753-764, 2013.
24. Zhang, L., et al., "Translational motion compensation for ISAR imaging under low SNR by minimum entropy," EURASIP Journal on Advances in Signal Processing 2013, Vol. 2013, No. 33, 1-19, 2013.
25. Chen, C. C. and H. C. Andrews, "Target-motion-induced radar imaging," IEEE Transactions on Aerospace and Electronic Systems, Vol. 16, No. 1, 2-14, Jan. 1980.
26. Wang, J. and D. Kasilingam, "Global range alignment for ISAR," IEEE Transactions on Aerospace and Electronic Systems, Vol. 39, No. 1, 351-357, Jan. 2003.
27. Zhu, D., L. Wang, Y. Yu, Q. Tao, and Z. Zhu, "Robust ISAR range alignment via minimizing the entropy of the average range profile," IEEE Geoscience and Remote Sensing Letters, Vol. 6, No. 2, 204-208, Apr. 2009.
28. Itoh, T. M. and G. W. Donohoe, "Motion compensation for ISAR via centroid tracking," IEEE Transactions on Aerospace and Electronic Systems, Vol. 32, No. 7, 1191-1197, Jul. 1996.
29. Ye, W., T. S. Yeo, and Z. Bao, "Weighted least-squares estimation of phase errors for SAR/ISAR autofocus," IEEE Transactions on Geosciences and Remote Sensing, Vol. 37, No. 9, 2487-2494, Sep. 1999.
30. Eichel, P. H. and C. V. Jakowatz, "Phase-gradient algorithm as an optimal estimator of the phase derivative," Optics Letters, Vol. 14, No. 20, 1101-1103, 1989.
31. Li, X., G. Liu, and J. Ni, "Autofocusing of ISAR imaging based on entropy minimization," IEEE Transactions on Aerospace and Electronic Systems, Vol. 35, No. 4, 1240-1251, Apr. 1999.
32. Martorella, M., F. Berizzi, and B. Haywood, "Contrast maximization based technique for 2-D ISAR autofocusing," IEE Proceedings on Radar, Sonar and Navigation, Vol. 52, No. 4, 253-262, Apr. 2005.
33. Xu, R., Z. Cao, and Y. Liu, "A new method of motion compensation for ISAR," 1990 IEEE International Radar Conference, 234-237, Arlington, VA, May 7-10, 1990.