volume | PIER Journals

Abstract

Two techniques are described for the calibration of ground-based (GB) circularly polarized (CP) full polarimetric radars. The techniques are based on the point target calibration approach that uses various types of canonical reflectors with different orientations. Specifically, the calibration methods for linearly polarized (LP) radar proposed by Wiesbeck et al. and Gau et al. are selected and adapted to CP with suitable reflectors. The applicability of the techniques is examined through C-band scatterometric and synthetic aperture radar (SAR) measurements in an anechoic chamber. For the scatterometric mode, comparisons of calibrated channel imbalances with theoretical values show agreement within ±0.3 dB in amplitude and ±5˚ in phase. The crosstalk between the channels is also reduced by ~5 to 30 dB after calibration. For the SAR mode, calibrated scattering matrix of a vertical wire target exhibits significant elimination of distortions between channel amplitudes and phases. The effect of calibration on target parameter retrieval is also investigated through the Cloud-Pottier eigenvector-based decomposition. Both calibration techniques are shown to yield improved accuracy of entropy-alpha (H-α) distributions and orientation angle (β) values.

1. Moreira, A., P. Prats-Iraola, M. Younis, G. Krieger, I. Hajnsek, and K. P. Papathanassiou, "A tutorial on synthetic aperture radar," IEEE Geoscience and Remote Sensing Magazine, Vol. 1, No. 1, 6-43, 2013.
doi:10.1109/MGRS.2013.2248301

2. Henderson, F. M. and J. L. Anthony, Principles and Applications of Imaging Radar, John Wiley and Sons, NY, 1998.

3. Lee, J. S. and E. Pottier, Polarimetric Radar Imaging from Basics to Applications, CRC Press, FL, 2009.
doi:10.1201/9781420054989

4. Cloude, S., Polarization: Applications in Remote Sensing, Oxford University Press, 2010.

5. Zhou, Z. S., W. M. Boerner, and M. Sato, "Development of a ground-based polarimetric broadband SAR system for noninvasive ground-truth validation in vegetation monitoring," IEEE Transactions on Geoscience and Remote Sensing, Vol. 42, No. 9, 1803-1810, 2004.
doi:10.1109/TGRS.2004.832248

6. Malz, E., R. Zetik, P. Semashko, R. S. Thoma, and A. G. Ariza, "Polarimetric ultrawideband radar," 2012 IEEE International Geoscience and Remote Sensing Symposium, 5919-5922, Munich, 2012.
doi:10.1109/IGARSS.2012.6352261

7. Zhou, Z. S. and S. Cloude, "Structural parameter estimation of Australian flora with a groundbased polarimetric radar interferometer," 2006 IEEE International Symposium on Geoscience and Remote Sensing, 71-74, Denver, 2006.
doi:10.1109/IGARSS.2006.23

8. Martorella, M., E. Giusti, A. Capria, F. Berizzi, and B. Bates, "Automatic target recognition by means of polarimetric ISAR images and neural networks," IEEE Transactions on Geoscience and Remote Sensing, Vol. 47, No. 11, 3786-3794, 2009.
doi:10.1109/TGRS.2009.2025371

9. Lopez-Sanchez, J. M., J. D. Ballester-Berman, V. D. Navarro-Sanchez, and F. Vicente-Guijalba, "Experimental validation of the interferometric coherence formulation in single-transmit mode," 2012 IEEE International Geoscience and Remote Sensing Symposium, 3114-3117, Munich, 2012.
doi:10.1109/IGARSS.2012.6350766

10. Salman, R., I. Willms, L. Reichardt, T. Zwick, W. Wiesbeck, and R. S. Thoma, "On buried weapon detection by means of scattering matrix decomposition for quad-polarized ultra-wideband radar," 2013 IEEE International Conference on Ultra-Wideband (ICUWB), 113-119, Sydney, 2013.
doi:10.1109/ICUWB.2013.6663832

11. Gomez-Dans, J. L., S. Quegan, and J. C. Bennett, "Indoor C-band polarimetric interferometry observations of a mature wheat canopy," IEEE Transactions on Geoscience and Remote Sensing, Vol. 44, No. 4, 768-777, 2006.
doi:10.1109/TGRS.2005.863861

12. Sri-Sumantyo, J. T., V. C. Koo, T. S. Lim, T. Kawai, T. Ebinuma, Y. Izumi, M. Z. Baharuddin, S. Gao, and K. Ito, "Development of circularly polarized synthetic aperture radar on-board UAV JX-1," International Journal of Remote Sensing, 1-12, 2017.

13. Rizki Akbar, P., J. T. Sri-Sumantyo, and H. Kuze, "A novel circularly polarized synthetic aperture radar (CP-SAR) system onboard a spaceborne platform," International Journal of Remote Sensing, Vol. 31, No. 4, 1053-1060, 2010.
doi:10.1080/01431160903156528

14. Izumi, Y., S. Demirci, M. Z. Baharuddin, J. T. Sri Sumantyo, and H. Yang, "Analysis of circular polarization backscattering and target decomposition using GB-SAR," Progress In Electromagnetics Research B, Vol. 73, 17-29, 2017.
doi:10.2528/PIERB16081701

15. Freeman, A., "Calibration of linearly polarized polarimetric SAR data subject to Faraday rotation," IEEE Transactions on Geoscience and Remote Sensing, Vol. 42, No. 8, 1617-1624, 2004.
doi:10.1109/TGRS.2004.830161

16. Goh, A. S., Bistatic synthetic aperture radar data processing and analysis, Doctoral dissertation, The University of Adelaide, 2012.

17. Van-Zyl, J. J., "Calibration of polarimetric radar images using only image parameters and trihedral corner reflector responses," IEEE Transactions on Geoscience and Remote Sensing, Vol. 28, No. 3, 337-348, 1990.
doi:10.1109/36.54360

18. Quegan, S., "A unified algorithm for phase and cross-talk calibration of polarimetric data-theory and observations," IEEE Transactions on Geoscience and Remote Sensing, Vol. 32, No. 1, 89-99, 1994.
doi:10.1109/36.285192

19. Ainsworth, T. L. and J. S. Lee, "A new method for a posteriori polarimetric SAR calibration," 2001 IEEE International Geoscience and Remote Sensing Symposium — IGARSS, 420-422, Sydney, 2001.

20. Freeman, A., "SAR calibration: An overview," IEEE Transactions on Geoscience and Remote Sensing, Vol. 30, No. 6, 1107-1121, 1992.
doi:10.1109/36.193786

21. Yueh, S. H., J. A. Kong, and R. T. Shin, "Calibration of polarimetric radars using in-scene reflectors," Progress In Electromagnetics Research, Vol. 3, 451-510, 1990.

22. Sarabandi, K., F. T. Ulaby, and M. A. Tassoudji, "Calibration of polarimetric radar systems with good polarization isolation," IEEE Transactions on Geoscience and Remote Sensing, Vol. 28, No. 1, 70-75, 1990.
doi:10.1109/36.45747

23. Gau, J. R. and W. D. Burnside, "New polarimetric calibration technique using a single calibration dihedral," IEE Proceedings — Microwaves, Antennas and Propagation, Vol. 142, No. 1, 19-25, 1995.
doi:10.1049/ip-map:19951544

24. Whitt, M. W., F. T. Ulaby, P. Polatin, and V. V. Liepa, "A general polarimetric radar calibration technique," IEEE Transactions on Antennas and Propagation, Vol. 39, No. 1, 62-67, 1991.
doi:10.1109/8.64436

25. Chen, T. J., T. H. Chu, and F. C. Chen, "A new calibration algorithm of wide-band polarimetric measurement system," IEEE Transactions on Antennas and Propagation, Vol. 39, No. 8, 1188-1192, 1991.
doi:10.1109/8.97354

26. Wiesbeck, W. and D. Kahny, "Single reference, three target calibration and error correction for monostatic, polarimetric free space measurements," Proceedings of the IEEE, Vol. 79, No. 10, 1551-1558, 1991.
doi:10.1109/5.104229

27. Wiesbeck, W. and S. Riegger, "A complete error model for free space polarimetric measurements," IEEE Transactions on Antennas and Propagation, Vol. 39, No. 8, 1105-1111, 1991.
doi:10.1109/8.97343

28. Michelson, D. G., I. G. Cumming, and C. E. Livingstone, "A calibration algorithm for circular polarimetric radars," Journal of Electromagnetic Waves and Applications, Vol. 11, No. 5, 659-674, 1997.
doi:10.1163/156939397X00891

29. Michelson, D. G. and E. V. Jull, "Depolarizing trihedral corner reflectors for radar navigation and remote sensing," IEEE Transactions on Antennas and Propagation, Vol. 43, No. 5, 513-518, 1995.
doi:10.1109/8.384196

30. Sheen, D. R., E. L. Johansen, L. P. Elenbogen, and E. S. Kasischke, "The gridded trihedral: A new polarimetric SAR calibration reflector," IEEE Transactions on Geoscience and Remote Sensing, Vol. 30, No. 6, 1149-1153, 1992.
doi:10.1109/36.193791

31. Ruck, G. T., Radar Cross Section Handbook, Plenum Press, New York, 1970.
doi:10.1007/978-1-4899-5324-7

32. Izumi, Y., S. Demirci, M. Z. Baharuddin, and J. T. Sri-Sumantyo, "The polarimetric calibration method for ground-based circularly polarized synthetic aperture radar," PIERS Proceedings, 5131-5135, Shanghai, China, Aug. 8–11, 2016.

33. Soumekh, M. "Synthetic Aperture Radar Signal Processing," John Wiley and Sons, 1999.

34. Cloude, S. R. and E. Pottier, "An entropy based classification scheme for land applications of polarimetric SAR," IEEE Transactions on Geoscience and Remote Sensing, Vol. 35, No. 1, 68-78, 1997.
doi:10.1109/36.551935

Dr. Yuta Izumi

Dr. Sevket Demirci

Dr. Mohd Zafri Baharuddin

Dr. Mirza Muhammad Waqar

Prof. Josaphat Tetuko Sri Sumantyo