volume | PIER Journals

2011-04-29

Application of Super-SVA to Stepped-Chirp Radar Imaging with Frequency Band Gaps Between Subchirps

Wenshuai Zhai,

Dr. Wenshuai Zhai

Graduate University of the Chinese Academy of Sciences

China

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Yunhua Zhang

Prof. Yunhua Zhang

CAS Key Laboratory of Microwave Remote Sensing, National Space Science Center, Chinese Academy of Sciences

China

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Progress In Electromagnetics Research B, Vol. 30, 71-82, 2011

doi:10.2528/PIERB11032810 | Google Scholar

Abstract

It is well-known that the stepped-frequency chirp signal (SFCS) technique is one of the very effective approaches for achieving high range resolution in radar [1-5]. The SFCS is a train of subchirp pulses with up-stepped or down-stepped carrier frequencies. However, there exists a rang-Doppler coupling problem (RDCP) when applying this signal to practical radar system because longer time is needed for transmitting a complete burst compared with that needed for transmitting just a single chirp. In radar system design, if carrier frequency step (△f) can be larger than the bandwidth of subchirp (Bm), it will be very helpful for using less number of subchirps to obtain high resolution and at the same time the influence of RDCP on imaging quality can be reduced. However the spectrum of transmitted signal is not continuous but with bandwidth gaps existing when Δf > Bm, and it will finally lead to high grating lobes in range profile. In this paper, the Super-SVA technique is applied to radar signal processing to solve the grating lobe problem arisen from bandwidth gaps. Super-SVA has been proven to be a very effective method used for extrapolating signal spectrum. Simulation and experiment results for moving train imaging are presented to show that the algorithm works very well.

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Wenshuai Zhai, and Yunhua Zhang, "Application of Super-SVA to Stepped-Chirp Radar Imaging with Frequency Band Gaps Between Subchirps," Progress In Electromagnetics Research B, Vol. 30, 71-82, 2011.
doi:10.2528/PIERB11032810

References

1. Levanon, N. and E. Mozeson, Radar Signals, John Wiley & Sons, 2003.

2. Levanon, N., "Stepped-frequency pulse-train radar signal," IEE Proceedings Radar, Sonar and Navigation, Vol. 149, No. 6, 297-309, 2002.
doi:10.1049/ip-rsn:20020432 Google Scholar

3. Zhang, Q., T. S. Yeo, and G. Du, "ISAR imaging in strong ground clutter by using a new stepped-frequency signal format," IEEE Trans. Geosci. Remote Sensing, Vol. 41, No. 5, 948-9521, 2003.
doi:10.1109/TGRS.2003.811760 Google Scholar

4. Gladkova, I. and D. Chebanov, "Suppression of grating lobes in stepped-frequency train," Proceedings of IEEE International Radar Conference, 371-376, May 2005.
doi:10.1109/RADAR.2005.1435853 Google Scholar

5. Doerry, A. W., "SAR processing with stepped chirps and phased array antennas," SANDIA Report, 2006-5855, 2006. Google Scholar

6. Zhai, W., X. Zhang, and Y. Zhang, "Signal processing and resolution analysis of Ka-band stepped-frequency radar in moving target imaging experiment," Global Symposium on Millimeter Waves 2010 (GSMM 2010), 83-86, Apr. 2010. Google Scholar

7. Stankwitz, H. C. and M. R. Kosek, "Super-resolution for SAR/ISAR RCS measurement using spatially variant apodization," Proceedings of Antenna Measurement Techniques Association (AMTA) 17th Annual Meeting and Symposium, 251-256, Nov. 1995 . Google Scholar

8. Xu, X. and R. M. Narayanan, "Enhanced resolution in SAR/ISAR imaging using iterative sidelobe apodization," IEEE Transactions on Image Processing, Vol. 14, No. 4, 537-547, Apr. 2005.
doi:10.1109/TIP.2004.841198 Google Scholar

9. Stankwitz, H. C. and M. R. Kosek, "Sparse aperture fill for SAR using Super-SVA," Proceedings of the 1996 IEEE National Radar Conference, 70-75, May 1996.
doi:10.1109/NRC.1996.510659 Google Scholar

10. Zhuang, L., X. Liu, and Z. Zhou, "Enhanced resolution for sparse aperture radar imaging using Super-SVA," Proceedings of Asia-Pacific Microwave Conference, 95-98, 2007. Google Scholar

11. Zhai, W.-S. and Y.-H. Zhang, "Apply Super-SVA to processing stepped frequency chirp signal with bandwidth gaps," Journal of Electronics & Information Technology, Vol. 31, No. 12, 2848-2852, 2009. Google Scholar

12. Zhai, W. and Y. Zhang, "Apply Super-SVA to SAR imaging with both aperture gaps and bandwidth gaps,", Vol. 57, 39-42, 2009. Google Scholar

13. Zhang, Y., J.Wu, and H. Li, "Two simple and effiicient approaches for compressing stepped chirp signals," AMPC, Vol. 2, 690-693, Dec. 4 2005. Google Scholar

14. Zhang, Y., H. Li, and J. Wu, "Subaperture processing method for stepped frequency chirp signal," System Engineering and Electronics, Vol. 28, No. 1, 1-6, Jan. 2006. Google Scholar

15. Stankwitz, H. C., R. J. Dallaire, and J. R. Fienup, "Nonlinear apodization for sidelobe control in SAR imagery," IEEE Trans. on Aerospace and Electronic Systems, Vol. 31, No. 1, 267-279, 1995.
doi:10.1109/7.366309 Google Scholar