volume | PIER Journals

Abstract

A near-field three dimensional imaging algorithm for circular SAR is proposed in this paper. It adopts the theory of spherical wave decomposition to transform Green function to a superposition of plane wave components. Using this relation, the image-reconstruction can be implemented in frequency domain instead of in spatial domain, which simplifies the solving process of target reflectivity function, and allows for the target to be near to the radar. Through compensating phase factor and filtering at each elevation, we firstly get the ground CSAR signal of each elevation in frequency domain. Then, performing two dimensional inverse nonuniform fast Fourier transform and accumulating the results of all azimuth angles, the reconstructed two dimensional image corresponding to an elevation is achieved. Finally, using reconstructed image datum of all elevation, the three dimensional image of target is obtained. To demonstrate the imaging performance of our method, numerical simulations and experiments are conducted. By comparing the results with the focusing operator algorithm and the back-projection algorithm, it is found that the proposed algorithm is more efficient and can obtain a good imaging performance.

1. Sheen, D. M., D. L. McMakin, and T. E. Hall, "Three-dimensional millimeter-wave imaging for concealed weapon detection," IEEE Trans. on Microwave Theory and Techniques, Vol. 49, No. 9, 1581-1592, Sep. 2001.
doi:10.1109/22.942570 Google Scholar

2. Sheen, D. M., D. L. McMakin, and T. E. Hall, "Near-field three-dimensional radar imaging techniques and applications," Applied Optics, Vol. 49, No. 19, E83-E93, 2010.
doi:10.1364/AO.49.000E83 Google Scholar

3. Oka, S., H. Togo, N. Kukutsu, and T. Nagatsuma, "Latest trends in millimeter-wave imaging technology," Progress In Electromagnetics Research Letters, Vol. 1, 197-204, 2008.
doi:10.2528/PIERL07120604 Google Scholar

4. Demirci, S., H. Cetinkaya, E. Yigit, C. Ozdemir, and A. Vertiy, "A study on millimeter-wave imaging of concealed objected: Application using back-projection algorithm," Progress In Electromagnetics Research, Vol. 128, 457-477, 2012. Google Scholar

5. Manfred, H., B. Gunnar, and E. Helmut, "Millimetre wave near-field SAR scanner for concealed weapon detection," Proceedings of EUSAR 2008, 151-154, Friedrichshafen, Germany, 2008. Google Scholar

6. Harmer, S. W., S. E. Cole, N. J. Bowring, N. D. Rezgui, and D. Andrews, "On body concealed weapon detection using a phased antenna array," Progress In Electromagnetics Research, Vol. 124, 187-210, 2012.
doi:10.2528/PIER11112105 Google Scholar

7. Grokhotkov, I. N. and A. Kuznetsov, "A concept of microwave system for the inspection of people and luggage," Proceedings of EUSAR 2008, 155-159, Friedrichshafen, Germany, 2008. Google Scholar

8. Bjarnason, J. E., T. L. Chan, A. W. Lee, M. A. Celis, and E. R. Brown, "Millimeter-wave, terahertz, and mid-infrared transmission through common clothing," Applied Physics Letters, Vol. 85, No. 4, 197-204, 2004.
doi:10.1063/1.1771814 Google Scholar

9. Tonouchi, M., "Cutting-edge terahertz technology," Nature Photonics, Vol. 1, No. 2, 97-105, 2007.
doi:10.1038/nphoton.2007.3 Google Scholar

10. Li, J. and Y. Pi, "Research on the 3D imaging algorithm of spin target based on the Hough transform," EURASIP Journal on Wireless Communications and Networking, Vol. 90, 2013, doi:10.1186/1687-1499-2013-90. Google Scholar

11. Nicholson, K. J. and C. H. Wang, "Improved near-field radar cross-section measurement technique," IEEE Antennas and Wireless Propagation Letters, Vol. 8, 1103-1106, 2009.
doi:10.1109/LAWP.2009.2033951 Google Scholar

12. Yan, W., J.-D. Xu, N.-J. Li, and W.-X. Tan, "A novel fast near-field electromagnetic imaging method for full rotation problem," Progress In Electromagnetics Research, Vol. 120, 387-401, 2011. Google Scholar

13. Li, C. and D. Y. Zhu, "A residue-pairing algorithm for InSAR phase unwrapping," Progress In Electromagnetics Research, Vol. 95, 341-354, 2009.
doi:10.2528/PIER09070706 Google Scholar

14. Ren, X. Z., L. H. Qiao, and Y. Qin, "A three-dimensional imaging algorithm for tomography SAR based on improved interpolated array transform," Progress In Electromagnetics Research, Vol. 120, 181-193, 2011. Google Scholar

15. Xu, J., Y. Pi, and Z. Cao, "Bayesian compressive sensing in synthetic aperture radar imaging," IET Radar Sonar Navig., Vol. 6, No. 1, 2-8, 2012.
doi:10.1049/iet-rsn.2010.0375 Google Scholar

16. Tan, W. X., W. Hong, Y. P. Wang, and Y. R. Wu, "A novel spherical-wave three-dimensional imaging algorithm for microwave cylindrical scanning geometries," Progress In Electromagnetics Research, Vol. 111, 43-70, 2011.
doi:10.2528/PIER10100307 Google Scholar

17. Yu, L. and Y. Zhang, "A 3D target imaging algorithm based on two-pass circular SAR observations," Progress In Electromagnetics Research, Vol. 122, 341-360, 2012.
doi:10.2528/PIER11101901 Google Scholar

18. Knaell, K. K. and G. P. Cardillo, "Radar tomography for the generation of three-dimensional images," IEE Proc. of Radar, Sonar, Navigation, Vol. 142, No. 2, 54-60, 1995.
doi:10.1049/ip-rsn:19951791 Google Scholar

19. Broquetas, A., J. Palau, L. Jofre, and A. Cardama, "Spherical wave near-field imaging and radar cross-section measurement," IEEE Trans. Antennas Propag., Vol. 46, No. 5, 730-735, May 1998.
doi:10.1109/8.668918 Google Scholar

20. Broquetas, A., L. Jofre, and A. Cardama, "A near-field spherical wave inverse synthetic aperture radar technique," IEEE AP-S Symp. Dig., Vol. 2, 1114-1117, Chicago, IL, 1992. Google Scholar

21. Soumekh, M., Synthetic Aperture Radar Signal Processing with MATLAB Algorithms, Wiley, New York, 1999.

22. Soumekh, M., "Reconnaissance with slant plane circular SAR imaging," IEEE Transactions on Image Processing, Vol. 5, No. 8, 1252-1265, 1996.
doi:10.1109/83.506760 Google Scholar

23. Burki, J. and C. F. Barnes, "Slant plane CSAR processing using householder transform," IEEE Transactions on Image Processing, Vol. 17, No. 10, 1900-1907, 2008.
doi:10.1109/TIP.2008.2002161 Google Scholar

24. Dallinger, A., S. Schelkshorn, and J. Detlefsen, "Efficient ω-k algorithm for circular SAR and cylindrical reconstruction areas," Advances in Radio Science,, Vol. 4, No. 10, 85-91, 2006.
doi:10.5194/ars-4-85-2006 Google Scholar

25. Kou, L. L., X. Q. Wang, J. S. Chong, M. S. Xiang, and M. H. Zhu, "Circular SAR processing using an improved omega-k type algorithm," Journal of Systems Engineering and Electronics, Vol. 21, No. 4, 572-579, 2010. Google Scholar

26. Olivadese, D., E. Giusti, F. Berizzi, M. Martorella, and F. Lombardini, "Near field 3D circular SAR imaging," 3rd International Asia-Pacic Conference on Synthetic Aperture Radar (APSAR), 2011. Google Scholar

27. Balanis, C. A., Antenna Theory Analysis and Design, 3rd Edition, John Wiley and Sons, New York, USA, 2005.

28. Fessler, J. A. and B. P. Sutton, "Nonuniform fast fourier transforms using min-max interpolation," IEEE Transactions on Signal Processing, Vol. 51, No. 2, 560-574, 2003.
doi:10.1109/TSP.2002.807005 Google Scholar

29. Ishimaru, A., T. K. Chan, and Y. Kuga, "An imaging technique using confocal circular synthetic aperture radar," IEEE Transactions on Geoscience and Remote Sensing, Vol. 36, No. 5, 1524-1530, 1998.
doi:10.1109/36.718856 Google Scholar

30. Bryant, M. L., L. L. Gostin, and M. Soumekh, "3-D E-CSAR imaging of a T-72 tank and synthesis of its SAR reconstructions," IEEE Transactions on Aerospace and Electronic Systems, Vol. 39, No. 1, 211-227, 2003.
doi:10.1109/TAES.2003.1188905 Google Scholar

Dr. Biao Zhang

Dr. Yiming Pi

Dr. Rui Min