Airborne

Airborne GPR

Lorenzo Crocco

21/3/2013

 

Airborne GPR, operated on aircrafts, UAV or helicopters, is a surveying technology that is attractive for its capability of providing information over wide, possibly inaccessible, areas. In particular, it can provide information at an intermediate spatial scale with respect to satellite monitoring or ground based observations. For this reason, it can be useful to validate (or support the interpretation of) satellite images using parameters that are valid on a broader spatial scale (with respect to local surveys and) and, at the same time, can be integrated with ground observations aimed at a more punctual monitoring.

Airborne GPR has been exploited or proposed in several application fields as different as ice thickness profiling [1,2,3,4], which is possibly the “oldest application framework of airborne GPR, basal water detection [5], monitoring of oil spills in snow [6], detection of avalanche victims [7,8], estimation of river discharge [9] or soil moisture [10], measurement of snow accumulation or depth [11,12,13,14], estimation of peat thickness [15] and minefield detection [16,17,18,19].

Typically, operational frequencies in the VHF-UHF band are exploited, although higher frequency can be used depending on the specific application (in terms of required penetration depth and resolution). For instance, in [2] the Ka band is exploited to sound the shallow layer of freshwater ice. Historically, the first examples of airborne GPR systems are based on pulsed radar architecture, whereas stepped frequency radars are become more popular in the recent years.

It is important to remark that, due to the different measurement configuration with respect to “standard” GPR operations, the development of processing tools (based for instance on migration, SAR focusing or inversion tomography) calls for specific tools for modelling the wave-ground-subsurface interaction [20,21] as well as to properly revisit processing algorithms [24,25,26,27].

From a hardware point of view, the design of airborne GPR systems also entails specific solutions, which have to account for possible interference with other EM sources, as well as with the equipment of the aircraft [28,29,30,31,32,33].

 

Ice thickness profiling

[1] S. A. Arcone and A. J. Delaney, “Airborne river-ice thickness profiling with helicopter-borne UHF shot pulse radar”, Journal of Glaciology, vol. 33, n. 115, pp. 330-340, 1987

[2] N. E. Yankielun, S. A Arcone, R. K Crane, “Thickness profiling of freshwater ice using millimiter wave FM-CW Radar”, IEEE Transactions on Geoscience and Remote Sesing, vol. 30, no. 5, pp. 1094-1100, 1992

[3] Lalumiere, L., Prinsenberg, S., “Integration of a helicopter-based ground penetrating radar (GPR) with a laser, video and GPS system”, Proceedings of the International Offshore and Polar Engineering Conference, pp. 658-665. (2009).

 

Antarctica Crevasses

[4] Arcone, Steven A., Delaney, Allan J., “GPR images of hidden crevasses in Antarctica”, Proceedings of SPIE - The International Society for Optical Engineering, 4084, pp. 760-765. (2000).

[5] Peters, M.E., Blankenship, D.D., Carter, S.P., Kempf, S.D., Young, D.A., Holt, J.W., “Along-track focusing of airborne radar sounding data from west antarctica for improving basal reflection analysis and layer detection”, IEEE Transactions on Geoscience and Remote Sensing, 45 (9), pp. 2725-2736, (2007).

 

Oil spills (under snow)

[6] J. H. Bradford, D. F. Dickins and P. J. Brandvik, “Assessing the potential to detect oil spills in and under snow using airborne groumd-penetrating radar”, geophysics, vol. 75, no.2 pp. G1-G12, 2010.

 

Avalanche victims

[7] A. Heilig, M. Schneebeli, and W. Fellin, “Feasibility study of a system for airborne detection of avalanche victims with ground penetrating radar and a possible automatic location algorithm,” Cold Regions Sci. Technol., vol. 51, no. 2/3, pp. 178–190, Feb. 2008.

[8] F. Fruehauf, A. Heilig, M. Schneebeli, W. Fellin, and O. Scherzer, “Experiments and Algorithms to Detect Snow Avalanche Victims Using Airborne Ground-Penetrating Radar”, IEEE Transactions On Geoscience And Remote Sensing, Vol. 47, No. 7, pp. 2240-2251, 2009.

 

River discharge

[9] N. B. Melcher, J. E. Costa, F. P. Haeni, R. T. Cheng, E. M. Thurman, M. Buursink, K. R. Spicer, E. Hayes, W. J. Plant, W. C. Keller, K. Hayes, "River discharge measurements by using helicopter-mounted radar", Geophys. Res. Lett., vol. 29, n. 22, pp. 41-1 - 41-4, 2002.

 

Soil moisture

[10] Chanzy, A., Tarussov, A., Judge, A., Bonn, F., “Soil water content determination using a digital ground-penetrating radar”, Soil Science Society of America Journal, 60 (5), pp. 1318-1326. (1996)

 

Snow accumulation

[11] Machguth, H. , Eisen, O., Paul, F., Hoelzle, M., “Strong spatial variability of snow accumulation observed with helicopter-borne GPR on two adjacent Alpine glaciers”, Geophysical Research Letters, 33 (13), art. no. L13503, 2006.

 

Snow depth & buried targets

[12] Negi, H.S., Snehmani, Thakur, N.K., Sharma, J.K., “Estimation of snow depth and detection of buried objects using airborne Ground Penetrating Radar in Indian Himalaya”, Current Science, 94 (7), pp. 865-870, 2008.

[13] Marchand, W.-D., Killingtveit, Ö. Wilen, P.b , Wikstrom, P., “Comparison of ground-based and airborne snow depth measurements with georadar systems, case study”, Nordic Hydrology, 34 (5), pp. 427-448, 2003.

[14] N. Galin, A. Worby, T. Markus, C. Leuschen, and P.Gogineni, “Validation of Airborne FMCW Radar Measurements of Snow Thickness Over Sea Ice in Antarctica”, IEEE TRANSACTIONS ON GEOSCIENCE AND REMOTE SENSING, VOL. 50, NO. 1, pp.3-12, 2012

 

Lithology

[15] Grandjean, G., Paillou, P., Dubois-Fernandez, P., August-Bernex, T., Baghdadi, N.N., Achache, J., “Subsurface structures detection by combining L-band polarimetric SAR and GPR data: Example of the pyla dune (France)”, IEEE Transactions on Geoscience and Remote Sensing, 39 (6), pp. 1245-1258, 2001.

 

Peat analysis

[16] Pelletier, R.E., Davis, J.L., Rossiter, J.R., “Peat analyses in the Hudson Bay Lowlands using ground penetrating radar”, Digest - International Geoscience and Remote Sensing Symposium (IGARSS), 4, pp. 2141-2144. (1991).

 

Landmine detection

[17] Moussally, G., Fries, R., Bortins, R., “Ground-penetrating, synthetic-aperture radar for wide-area airborne minefield detection”, Proceedings of SPIE - The International Society for Optical Engineering, 5415 (PART 2), pp. 1042-1052 (2004).

[18] Moussally, G., Breiter, K., Rolig, J., ”Wide-area landmine survey and detection system”, Proceedings of the Tenth International Conference Ground Penetrating Radar, GPR 2004, 2, pp. 693-696. (2004).

[19] Clark, W.W., Burns, B., Dorff, G., Plasky, B., Moussally, G., Soumekh, M., “Wideband radar for airborne minefield detection”, Proceedings of SPIE - The International Society for Optical Engineering, 6217 II, art. no. 621721, (2006).

[20] Aubry, W.M., Bonneau, R.J., Brown, R.D., Lynch, E.D., Wicks, M.C., Schneible, R.A., George, A.D., Krumme, M.A., “Airborne sensor concept to image shallow-buried targets”, IEEE National Radar Conference - Proceedings, pp. 233-236, (2002).

[21] Fijany, Amir, Collier, James B., Citak, Ari, “Advanced algorithms and high performance testbed for large scale site characterization and subsurface target detection using airborne ground penetrating SAR”, Proceedings of SPIE - The International Society for Optical Engineering, 3710 (II), pp. 1106-1117, (1999).

 

Numerical Modeling and inversion

[23] Carin, L., Sichina, J., Harvey, J.F., “Microwave underground propagation and detection”, IEEE Transactions on Microwave Theory and Techniques, 50 (3), pp. 945-952, (2002).

[24] M. Sen, P. L. Stoffa, R. K. Seifoullaev, J. T. Fokkema, “Numerical and Field Investigations of GPR: Toward an Airborne GPR”, Subsurface Sensing Technologies and Applications, vol.4 no.1, pp. 41-60, 2003.

[25] Catapano, I.; Crocco, L.; Krellmann, Y.; Triltzsch, G.; Soldovieri, F., "A Tomographic Approach for Helicopter-Borne Ground Penetrating Radar Imaging," Geoscience and Remote Sensing Letters, IEEE , vol.9, no.3, pp.378,382, May 2012

[26] Liu, S., Feng, Y., “Airborne GPR: Advances and numerical simulation”, International Geoscience and Remote Sensing Symposium (IGARSS), art. no. 6049949, pp. 3397-3400, 2011.

[27] Fu, L., Liu, S., Liu, L., “Numerical simulations and analysis for airborne ground penetrating radar”, 2012 14th International Conference on Ground Penetrating Radar, GPR 2012, pp. 200-203, (2012).

[28] Holt, J.W., Peters, M.E., Kempf, S.D., Morse, D.L., Blankenship, D.D., “Echo source discrimination in single-pass airborne radar sounding data from the Dry Valleys, Antarctica: Implications for orbital sounding of Mars”, Journal of Geophysical Research E: Planets, 111 (6), art. no. E06S24, (2006).

[29] Jin, T., Zhou, Z., “Refraction and dispersion effects compensation for UWB SAR subsurface object imaging”, IEEE Transactions on Geoscience and Remote Sensing, 45 (12), pp. 4059-4066. (2007).

[30] Doerry, A.W., Brock, B.C., Boverie, B., Cress, D., “Imaging targets embedded in a lossy half space with synthetic aperture radar”, International Geoscience and Remote Sensing Symposium (IGARSS), 4, pp. 2508-2512. (1994)

 

Systems design

[31] Vickers, R.S., "Design and applications of airborne radars in the VHF/UHF band," IEEE Aerospace and Electronic Systems Magazine, vol.17, no.6, pp.26,29, Jun 2002.

[32] Gregorwich, W., “Airborne ground penetrating radar system”, IEEE Aerospace Applications Conference Proceedings, 1, pp. 157-161. (1996).

 

Helicopter borne

[33] Eisenburger, D., Krellmann, Y., Lentz, H., Triltzsch, G., “Stepped-frequency radar system in gating mode: an experiment as a new helicopterborne gpr system for geological applications”, International Geoscience and Remote Sensing Symposium (IGARSS), 1 (1), art. no. 4778816, pp. I153-I156, 2008.

[34] Eisenburger, D., Lentz, H., Jenett, M., “Helicopter-borne GPR systems: A way from ICE thickness measurements to geological applications”, Proceeedings of The 2008 IEEE International Conference on Ultra-Wideband, ICUWB 2008, 3, art. no. 4653441, pp. 161-165. (2008).

[35] Gundelach, V., Blindow, N., Buschmann, U., Salat, C., Krellmann, Y., “Exploration of geological structures with GPR from helicopter and on the ground in the Letzlinger Heide (Germany)”, Proceedings of the 13th Internarional Conference on Ground Penetrating Radar, GPR 2010, art. no. 5550092, (2010).

[36] Blindow, N., Salat, C., Gundelach, V., Buschmann, U., Kahnt, W., “Performance and calibration of the helicoper GPR system BGR-P30”,2011 6th International Workshop on Advanced Ground Penetrating Radar, IWAGPR 2011, art. no. 5963896, (2011).

[37] Krellmann, Y., Triltzsch, G., “HERA-G - A new helicopter GPR based on gated stepped frequency technology”, 2012 14th International Conference on Ground Penetrating Radar, GPR 2012, pp. 156-159, (2012).

[38] Blindow, N., Salat, C., Casassa, G., “Airborne GPR sounding of deep temperate glaciers - Examples from the Northern Patagonian Icefield”, 2012 14th International Conference on Ground Penetrating Radar, GPR 2012, pp. 664-669, (2012).

[39] Catapano, I., Crocco, L., Soldovieri, F., Lanari, R., Alberti, G., Adirosi, D., Facchinetti, C., Longo, F., Formaro, R., Persico, R., “Airborne GPR surveys via tomographic imaging: An analysis of the reconstruction capabilities”, 2012 14th International Conference on Ground Penetrating Radar, GPR 2012, pp. 310-314, (2012).