volume | PIER Journals

Abstract

Sidelobes of strong targets substantially impact image quality of synthetic aperture radar (SAR) using linear frequency modulation (LFM) waveform, especially in urban areas. A novel space-borne azimuth multi-channel SAR scheme with ultra-low range sidelobe-ratio (RSLR) performance was proposed, employing complete complementary sequence (CC-S) coding waveform. The CC-S waveform was utilized to acquire ultra-low RSLR performance in range direction. Azimuth multi-channel scheme was introduced, to compensate reduction of effective PRF due to employing CC-S, and to mitigate azimuth resolution lost resulted from strong azimuth weighting, in order to implement low side-lobe performance in both range and azimuth direction. The method for pre-processing the CC-S based multi-channel SAR data was proposed, which would both compensate receiving time difference of sub-sequences and reconstruct azimuth spectrum of multi-channel SAR data. Furthermore, the corresponding image formation algorithm for accurately focusing raw data of the SAR system was also proposed. Computer simulation results were presented, which demonstrated the validity of the proposed SAR scheme and image formation algorithm.

1. Wang, Y., J. Li, J. Chen, H. Xu, and B. Sun, "A novel non-interpolation polar format algorithm using non-lineal flight trajectories and auto-adaptive PRF technique," Progress In Electromagnetics Research, Vol. 122, 155-173, 2012. Google Scholar

2. Chen, J., J. Gao, Y. Zhu, W. Yang, and P. Wang, "A novel image formation algorithm for high-resolution wide-swath spaceborne SAR using compressed sensing on azimuth displacement phase center antenna," Progress In Electromagnetics Research, Vol. 125, 527-543, 2012. Google Scholar

3. Ismail, A., M. Mohamadpoor, R. S. A. Raja Abdullah, and A. F. Abas, "A circular synthetic aperture radar for on-the-ground object detection," Progress In Electromagnetics Research, Vol. 122, 269-292, 2012. Google Scholar

4. Sun, J., S. Mao, G.Wang, and W. Hong, "Extended exact transfer function algorithm for bistatic SAR of translational invariant case," Progress In Electromagnetics Research, Vol. 99, 89-108, 2009. Google Scholar

5. Xu, W., P. P. Huang, and Y. K. Deng, "Multi-channel SPCMB-TOPS SAR for high-resolution wide-swath imaging," Progress In Electromagnetics Research, Vol. 116, 533-551, 2011. Google Scholar

6. Zhang, M., Y. W. Zhao, H. Chen, and W. Q. Jiang, "SAR imaging simulation for composite model of ship on dynamic ocean scene," Progress In Electromagnetics Research, Vol. 113, 395-412, 2011. Google Scholar

7. Stankwitz, H. C., R. J. Dallaire, and J. R. Fienup, "Spatially variant apodization for sidelobe control in SAR imagery," Radar Conference, 132-137, 1994. Google Scholar

8. Thomas, G., B. C. Flores, and J. Sok-Son, "SAR sidelobe apodization using the Kaiser window," Imaging Processing, 709-712, 2000. Google Scholar

9. Zhang, P., Z. Li, J. Zhou, and Q. Chen, "A new SAR superresolution imaging algorithm based on adaptive sidelobe reduction," Proc. IGARSS, 2789-2792, Toronto, Canada, 2011. Google Scholar

10. Li, S. F., J. Chen, L. Q. Zhang, and Y. Q. Zhou, "Image formation algorithm for missile borne MMW SAR with phase coded waveform," Proc. Radar Conference, 1-4, 2009. Google Scholar

11. Durai, R. S. R., "A class of optimal complete-complementary codes of different length," Proc. Signal Design and Its Applications in Communications, 92-95, 2011. Google Scholar

12. Huang, X. and Y. Li, "Polyphase scalable complete complementary sets of sequences," The 8th International Conference on Communication Systems, Vol. 2, 810-814, 2002. Google Scholar

13. Suehiro, N., "Complete complementary code composed of N-multiple-shift orthogonal sequences," IEICE Trans., Vol. J65-A, 1247-1253, 1982. Google Scholar

14. Gerhard, K., G. Nicolas, and M. Alberto, "Unambiguous SAR signal reconstruction from nonuniform displaced phase center sampling," IEEE Geoscience and Remote Sensing Letters, Vol. 1, No. 4, 260-264, Oct. 2004. Google Scholar

15. Chua, M. Y. and V. C. Koo, "FPGA-based chirp generator for high resolution UAV SAR," Progress In Electromagnetics Research, Vol. 99, 71-88, 2009. Google Scholar

16. Wei, S. J., X. L. Zhang, J. Shi, and G. Xiang, "Sparse reconstruction for SAR imaging based on compressed sensing," Progress In Electromagnetics Research, Vol. 109, 63-81, 2010. Google Scholar

17. Mao, X., D. Y. Zhu, and Z. D. Zhu, "Signatures of moving target in polar format spotlight SAR image," Progress In Electromagnetics Research, Vol. 92, 47-64, 2009. Google Scholar

18. Han, C., N. Suehiro, and T. Hashimoto, "N-shift cross-orthogonal sequences and complete complementary Codes," ISIT 2007, 2611-2615, Jun. 2007. Google Scholar

19. Li, S., J. Chen, L. Zhang, and Y. Zhou, "Construction of quadri-phase complete complementary pairs applied in MIMO radar systems," The 9th International Conference on Signal Processing (ICSP), 2298-2301, 2008. Google Scholar

20. Currie, A. and M. A. Brown, "Wide-swath SAR," Proc. Inst. Electr. Eng. F - Radar Signal Process., Vol. 139, No. 2, 122-135, Apr. 1992. Google Scholar

21. Gebert, N., G. Krieger, and A. Moreira, "Multichannel azimuth processing in ScanSAR and TOPS mode operation," IEEE Trans. Geosci. Remote Sens., Vol. 48, No. 7, 2994-3008, Jul. 2010. Google Scholar

22. Xu, W. and Y. Deng, "Multi-channel SAR system with reflector antenna for high-resolution wide-swath imaging," IEEE Antenna nd Wireless Propa. Lett., Vol. 9, 1123-1126, Dec. 2010. Google Scholar

23. Gebert, N., G. Krieger, and A. Moreira, "Digital beam forming on receive-techniques and optimization strategies for high resolution wide-swath SAR imaging," IEEE Transaction on Aerospace and Electronic Systems, Vol. 45, No. 2, 564-592, Apr. 2009. Google Scholar

24. Cumming, I. G. and F. H. Wong, Digital Processing of Synthetic Aperture Radar Data: Algorithm and Implementation, Artech House, Norwood, MA, 2005.

Prof. Jie Chen

Dr. Yanqing Zhu

Dr. Pengbo Wang

Dr. Wei Yang