In this paper, we propose a new retrieval technique to estimate the dielectric permittivity of the sub-soil materials of a stratified structure. The core of the retrieval procedure is a proper electromagnetic circuit model representing the realistic stratified media as a cascade of transmission line segments. Exploiting the analogies between the electrical parameters of the transmission line segments and the constitutive parameters of the materials of the multilayer structure, the propagation of the Ground Penetrating Radar (GPR) signal is equivalently represented as a pair of voltage and current waves propagating in the transmission line network. The effectiveness of the proposed retrieval technique is confirmed by proper experimental results. In particular, the retrieved electromagnetic parameters of the sub-soil materials are found to be consistent with the ones obtained by a direct characterization of the same materials. These results suggest that the proposed method can be successfully applied to the material characterization able to monitor several macroscopic properties of sub-soil materials.
2. Daniels, D. J., Ground Penetrating Radar, 2nd Edition, IEEE Press, 2004.
3. Orfanidis, S. J., Electromagnetic Waves and Antennas, 2008, Online Book Available at: http://www.ece.rutgers.edu/∼orfanidi/ewa.
4. Topp, C. G., J. L. Davis, and A. P. Annan, "Electromagnetic determination of soil water content: measurements in coaxial transmission lines," Water Resources Research, Vol. 16, 574-582, 1980.
5. Lunt, I. A., S. S. Hubbard, and Y. Rubin, "Soil moisture content estimation using ground penetrating radar reflection data," Journal of Hydrology, Vol. 307, 254-269, 2005.
6. Lambot, S., E. Slob, D. Chavarro, M. Lubczynski, and H. Vereecken, "Measuring soil surface water content in irrigated areas of southern Tunisia using full-waveform inversion of proxsimal GPR data," Near Surface Geophysics, 403-410, 2003.
7. Leng, Z., I. L. Al-Qadi, and P. Shangguan, "Field application of ground penetrating radar for asphalt mixture density measurement: A case study of Illinois Route 72 overlay," Transportation Research Board 91st Annual Meeting, 133-141, Washington, DC, Jan. 22–26, 2012.
8. Al-Qadi, I. L., Z. Leng, S. Lahouar, and J. Baek, "In-place hot-mix Asphalt density estimation using ground penetrating radar," Transportation Research Board 89st Annual Meeting, 19-27, Washington, DC, Jan. 10–14, 2010.
9. Walker, P. D. and M. R. Bell, "Subsurface permittivity estimation from ground-penetrating radar measurements," 2000 Radar Conference, 341-346, Alexandria, VA, May 7–12, 2000.
10. Giannopoulos, A. and N. Diamanti, "A numerical investigation into the accuracy of determining dielectric properties and thickness of pavement layers using reflection amplitude GPR data," Int. Conf. on Ground Penetrating Radar, 655-658, Delft, The Netherlands, Jun. 21–24, 2004.
11. Liu, H. and M. Sato, "Robust estimation of dielectric constant by GPR using an antenna array," 2011 IEEE International Geoscience and Remote Sensing Symposium, 178-181, Vancouver, BC, Jul. 24–29, 2011.
12. Minet, J., S. Lambot, E. Slob, and M. Vanclooster, "Soil surface water content estimation by full-waveform GPR signal inversion in the presence of thin layers," IEEE Trans. Geoscience Remote Sensing, Vol. 48, No. 3, 1138-1150, Mar. 2010.
13. Pozar, D. M., Microwave Engineering, 4th Edition, John Wiley & Sons, NewYork, 2011.
14. Ramaccia, D., F. Scattone, F. Bilotti, and A. Toscano, "Broadband compact horn antennas by using EPS-ENZ metamaterial lens," IEEE Trans. Ant. Propag., Vol. 61, No. 6, 2929-2937, Jun. 2013.
15. Bilotti, F., L. Di Palma, D. Ramaccia, and A. Toscano, "Self-filtering low-noise horn antenna for satellite applications," IEEE Ant. Wireless Propag. Lett., Vol. 11, 354-357, 2012.
16. Ramaccia, D., L. Di Palma, G. Guarnieri, S. Scaf`e, A. Toscano, and F. Bilotti, "Balanced and unbalanced waveguide power splitters based on connected bi-omega particles," Elettronics Lett., Vol. 49, No. 24, 1504-1506, Nov. 2013.
17. Ramaccia, D., L. Di Palma, D. Ates, E. Ozbay, A. Toscano, and F. Bilotti, "Analytical model of connected bi-omega: Robust particle for the selective power transmission through sub-wavelength apertures," IEEE Trans. Ant. Propag., Vol. 62, No. 4, 2093-2101, Apr. 2014.
18. Ramaccia, D., F. Bilotti, and A. Toscano, "Analytical model of a metasurface consisting of a regular array of sub-wavelength circular holes in a metal sheet," Progress In Electromagnetics Research M, 209-219, 2011.
19. Ramaccia, D., A. Toscano, and F. Bilotti, "A new accurate model of high-impedance surfaces consisting of circular patches," Progress In Electromagnetics Research M, Vol. 21, 1-17, 2011.
20. Ramaccia, D., C. Guattari, F. Bilotti, and A. Toscano, "Metamaterial split-ring resonators for retrieval of soil electromagnetic properties," Proc. of Metamaterials’ 2013, 1-3, Bordeaux, France, Sep. 16–21, 2013.
21. CST Studio Suite, 2015, www.cst.com, .
22. Nishimoto, M., K. Tomura, and K. Ogata, "Waveform calibration of ground penetrating radars for identification of buried objects," IEICE Trans. Electron., Vol. 95-C, No. 1, 105-109, Jan. 2012.
23. Nishimoto, M., D. Yoshida, K. Ogata, and M. Tanabe, "Extraction of a target response from GPR data for identification of buried objects," IEICE Trans. Electron., Vol. 96-C, No. 1, 64-67, Jan. 2013.
24. Bogle, A., M. Havrilla, D. Nyquis, L. Kempel, and E. Rothwell, "Electromagnetic material characterization using a partially-filled rectangular waveguide," Journal of Electromagnetic Waves and Applications, Vol. 19, No. 10, 1291-1306, 2012.
25. Rohde & Schwarz, VNA ZVB-14, , URL: http://www.rohde-schwarz.it/product/ZVB.html.