We present a new RADAR system able to perform Phase Conjugation experiments over the ultrawideband [2-4] GHz. The system is equipped with a transmit/receive linear array made of eight antennas connected to a 2-port Vector Network Analyzer through eight independent couples of digitally-controlled RF attenuators and phase shifters. Thus, each channel can selectively transmit or receive and can as well attenuate and phase shift the RF signal. For each frequency, either the Phase Conjugation or the Decomposition of the Time Reversal Operator (DORT) is applied to the received signal and the appropriate amplitude and phase law is coded into the prototype; the focusing wave is then experimentally re-emitted by the array. The quality of the achieved backpropagation is evaluated both in frequency and time domain: in this sense we can speak of Time Reversal. The excellent agreement between measured and theoretical results validates the potential of our system.
"Time Reversal Experiments in the Microwave Range: Description of the Radar and Results," Progress In Electromagnetics Research,
Vol. 104, 427-448, 2010. doi:10.2528/PIER10030102
1. Fink, M., C. Prada, F. Wu, and D. Cassereau, "Self focusing in inhomogeneous media with time reversal acoustic mirrors," Proc. IEEE Ultrasonics Symposium, Vol. 2, 681-686, 1989.
2. Fink, M., "Time reversal of ultrasonics fields --- Part I: Basic principles," IEEE Trans. Ultrason., Ferroelectr., Freq. Control., Vol. 39, 555-566, 1992. doi:10.1109/58.156174
3. Fink, M., D. Cassereau, A. Derode, C. Prada, P. Roux, M. Tanter, J.-L. Thomas, and F. Wu, "Time-reversed acoustics," Rep. Prog. Phys., Vol. 63, No. 12, 1933-1995, 2000. doi:10.1088/0034-4885/63/12/202
4. Dubois, A., K. Belkebir, and M. Saillard, "Localization and characterization of two-dimensional targets buried in a cluttered environment ," Inv. Probl., Vol. 20, No. 6, S63-S79, 2004. doi:10.1088/0266-5611/20/6/S05
5. Belkebir, K., M. Saillard, O. Cmielewski, and H. Tortel, "Clutter rejection and inverse scattering," Proc. Journees de la Matiere Condensee, 210, Toulouse, France, 2006.
6. Belkebir, K., S. Bonnard, F. Pezin, P. Sabouroux, and M. Saillard, "Validation of 2D inverse scattering algorithms from multi-frequency experimental data," Journal of Electromagnetic Waves and Applications, Vol. 14, No. 12, 1637-1667, 2000. doi:10.1163/156939300X00437
7. Liu, X.-F., X.-F., B.-Z. Wang, S.-Q. Xiao, and J. H. Deng, "Performance of impulse radio UWB communications based on time reversal technique," Progress In Electromagnetics Research, Vol. 79, 401-413, 2008. doi:10.2528/PIER07102205
8. Xiao, S.-Q., J. Chen, X.-F. Liu, and B.-Z.Wang, "Spatial focusing characteristics of time reversal UWB pulse transmission with different antenna arrays," Progress In Electromagnetics Research B, Vol. 2, 223-232, 2008. doi:10.2528/PIERB07112203
9. Maaref, N., P. Millot, X. Ferriµeres, C. Pichot, and O. Picon, "Electromagnetic imaging method based on time reversal processing applied to through-the-wall target localization," Progress In Electromagnetics Research M, Vol. 1, 59-67, 2008. doi:10.2528/PIERM08013002
10. Zheng, W., Z. Zhao, Z.-P. Nie, and Q. H. Liu, "Evaluation of TRM in the complex through wall environment," Progress In Electromagnetics Research, Vol. 90, 235-254, 2009. doi:10.2528/PIER09011003
11. Lerosey, G., J. de Rosny, A. Tourin, A. Derode, and M. Fink, "Time reversal of wideband microwaves," Appl. Phys. Lett., Vol. 88, No. 15, 154101, 2006. doi:10.1063/1.2194009
12. Lerosey, G., J. de Rosny, A. Tourin, A. Derode, G. Montaldo, and M. Fink, "Time reversal of electromagnetic waves," Phys. Rev. Lett., Vol. 92, No. 19, 193904, 2004. doi:10.1103/PhysRevLett.92.193904
13. Khaleghi, A., G. El Zein, and I. Naqvi, "Demonstration of time-reversal in indoor ultra-wideband communication: Time domain measurement," Proc. IEEE International Symposium on Wireless Communication Systems , 465-468, Trondheim, Norway, 2007.
14. Liu, D., S. Vasudevan, J. Krolik, G. Bal, and L. Carin, "Electromagnetic time-reversal source localization in changing media: Experiment and analysis ," IEEE Trans. Antennas Propag., Vol. 55, No. 2, 344-354, 2007. doi:10.1109/TAP.2006.889807
15. Cresp, A., I. Aliferis, M. J. Yedlin, J.-Y. Dauvignac, and C. Pichot, "Time-domain processing of electromagnetic data for multiple-target detection ," AIP Conf. Proc., 3rd Conference on Mathematical Modeling of Wave Phenomena, Vol. 1106, No. 1, 204-213, 2009.
16. Prada, C. and M. Fink, "Eigenmodes of the time reversal operator: A solution to selective focusing in multiple-target media," Wave Motion, Vol. 20, 151-163, 1994. doi:10.1016/0165-2125(94)90039-6
17. Tortel, H., G. Micolau, and M. Saillard, "Decomposition of the time reversal operator for electromagnetic scattering," Journal of Electromagnetic Waves and Applications, Vol. 13, No. 5, 687-719, 1999. doi:10.1163/156939399X01113
18. Micolau, G. and M. Saillard, "D.O.R.T. method as applied to electromagnetic subsurface sensing," Radio Sci., Vol. 38, No. 3, S63-S79, 2003. doi:10.1029/2000RS002590
19. Chambers, D. H. and A. K. Gautesen, "Analysis of the time-reversal operator for a small spherical scatterer in an electromagnetic field," IEEE Trans. Antennas Propag., Vol. 52, No. 7, 1729-1738, 2004. doi:10.1109/TAP.2004.831323
20. Derode, A., P. Roux, and M. Fink, "Robust acoustic time reversal with high-order multiple scattering," Phys. Rev. Lett., Vol. 75, No. 7, 1729-1738, 2004.
21. Draeger, C. and M. Fink, "One-channel time reversal of elastic waves in a chaotic 2d-silicon cavity," Phys. Rev. Lett., Vol. 79, No. 3, 407-410, 1997. doi:10.1103/PhysRevLett.79.407
22. Kuperman, W. A., W. S. Hodgkiss, H. C. Song, T. Akal, C. Ferla, and D. R. Jackson, "Phase Conjugation in the ocean: Experimental demonstration of an acoustic time-reversal mirror," J. Acoust. Soc. Amer., Vol. 103, 25-40, 1998. doi:10.1121/1.423233
23. Mordant, N., C. Prada, and M. Fink, "Highly resolved detection and selective focusing in a waveguide using the D.O.R.T. method," J. Acoust. Soc. Amer., Vol. 105, No. 5, 2634-2642, 1999. doi:10.1121/1.426879
24. Yavuz, M. E. and F. L. Teixiera, "Space-frequency ultrawideband time-reversal imaging," IEEE Trans. Geosci. Remote Sens., Vol. 46, No. 4, 115-124, 2008.
25. Philippe, F. D., C. Prada, D. Clorennec, M. Fink, and T. Folegot, "Construction of the temporal invariants of the time-reversal operator," J. Acoust. Soc. Amer. Express Letters, Vol. 126, No. 1, EL8-EL13, 2009. doi:10.1121/1.3141881
26. Micolau, G., M. Saillard, and P. Borderies, "DORT method as applied to ultrawideband signals for detection of buried objects," IEEE Trans. Geosci. Remote Sens., Vol. 41, No. 8, 1813-1820, 2003. doi:10.1109/TGRS.2003.814139
27. Stewart, G. W., Matrix Algorithms-volume II: Eigensystems, SIAM, Philadelphia, New York, 1998.
28. Borcea, L., G. Papanicolaou, C. Tsogka, and J. Berryman, "Imaging and time reversal in random media," Inv. Prob., Vol. 18, No. 5, 1247-1279, 2002. doi:10.1088/0266-5611/18/5/303