Glacier bed surveying with helicopter-borne dual-polarization ground-penetrating radar
Traditionally, helicopter-borne ground-penetrating radar (GPR) systems are operated with a single pair of bistatic dipole antennas to measure the thickness of glaciers. We demonstrate numerically that the directivity of the radiation pattern of single airborne dipoles do not correspond to an ideal f...
| Main Authors: | , , , , , , |
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| Format: | Article |
| Language: | English |
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Cambridge University Press
2019-02-01
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| Series: | Journal of Glaciology |
| Subjects: | |
| Online Access: | https://www.cambridge.org/core/product/identifier/S0022143018000990/type/journal_article |
| _version_ | 1811155808090587136 |
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| author | LISBETH LANGHAMMER LASSE RABENSTEIN LINO SCHMID ANDREAS BAUDER MELCHIOR GRAB PHILIPP SCHAER HANSRUEDI MAURER |
| author_facet | LISBETH LANGHAMMER LASSE RABENSTEIN LINO SCHMID ANDREAS BAUDER MELCHIOR GRAB PHILIPP SCHAER HANSRUEDI MAURER |
| author_sort | LISBETH LANGHAMMER |
| collection | DOAJ |
| description | Traditionally, helicopter-borne ground-penetrating radar (GPR) systems are operated with a single pair of bistatic dipole antennas to measure the thickness of glaciers. We demonstrate numerically that the directivity of the radiation pattern of single airborne dipoles do not correspond to an ideal full-space solution if the antennas are employed at typical flight heights. These directionality effects can degrade the quality of the subsurface images significantly, when the GPR antennas are orientated unfavorably. Since an adjustment of the antenna orientation is impractical during flight, we have developed a novel dual-polarization helicopter-borne GPR system consisting of two orthogonal pairs of commercial antennas in broadside configuration. To overcome the image quality deficits of the individual channels, we apply a pseudo-scalar approach in which we combine the data of both polarizations. Results of helicopter-borne GPR surveys on two alpine glaciers in Switzerland reveal more coherent bedrock reflections in the summed data compared with single dipole pair profiles. Generally, the dual-polarization setup is more suitable than a single antenna systems, because it is more versatile and less prone to directional effects caused by the placement of the dipole antennas in relation to undulating subsurface reflectors. |
| first_indexed | 2024-04-10T04:40:55Z |
| format | Article |
| id | doaj.art-908042fa2d094d7fabac52cb4905e433 |
| institution | Directory Open Access Journal |
| issn | 0022-1430 1727-5652 |
| language | English |
| last_indexed | 2024-04-10T04:40:55Z |
| publishDate | 2019-02-01 |
| publisher | Cambridge University Press |
| record_format | Article |
| series | Journal of Glaciology |
| spelling | doaj.art-908042fa2d094d7fabac52cb4905e4332023-03-09T12:40:42ZengCambridge University PressJournal of Glaciology0022-14301727-56522019-02-016512313510.1017/jog.2018.99Glacier bed surveying with helicopter-borne dual-polarization ground-penetrating radarLISBETH LANGHAMMER0LASSE RABENSTEIN1LINO SCHMID2https://orcid.org/0000-0001-9826-4191ANDREAS BAUDER3MELCHIOR GRAB4PHILIPP SCHAER5HANSRUEDI MAURER6ETH Zurich, Institute of Geophysics, Zurich, SwitzerlandETH Zurich, Institute of Geophysics, Zurich, SwitzerlandETH Zurich, Institute of Geophysics, Zurich, SwitzerlandETH Zurich, Laboratory of Hydraulics, Hydrology and Glaciology, Zurich, SwitzerlandETH Zurich, Laboratory of Hydraulics, Hydrology and Glaciology, Zurich, SwitzerlandGEOSAT SA, Route du Manège 59b, 1950 Sion, SwitzerlandETH Zurich, Institute of Geophysics, Zurich, SwitzerlandTraditionally, helicopter-borne ground-penetrating radar (GPR) systems are operated with a single pair of bistatic dipole antennas to measure the thickness of glaciers. We demonstrate numerically that the directivity of the radiation pattern of single airborne dipoles do not correspond to an ideal full-space solution if the antennas are employed at typical flight heights. These directionality effects can degrade the quality of the subsurface images significantly, when the GPR antennas are orientated unfavorably. Since an adjustment of the antenna orientation is impractical during flight, we have developed a novel dual-polarization helicopter-borne GPR system consisting of two orthogonal pairs of commercial antennas in broadside configuration. To overcome the image quality deficits of the individual channels, we apply a pseudo-scalar approach in which we combine the data of both polarizations. Results of helicopter-borne GPR surveys on two alpine glaciers in Switzerland reveal more coherent bedrock reflections in the summed data compared with single dipole pair profiles. Generally, the dual-polarization setup is more suitable than a single antenna systems, because it is more versatile and less prone to directional effects caused by the placement of the dipole antennas in relation to undulating subsurface reflectors.https://www.cambridge.org/core/product/identifier/S0022143018000990/type/journal_articleglacier geophysicsground-penetrating radarice thickness measurementsmountain glaciersradio-echo sounding |
| spellingShingle | LISBETH LANGHAMMER LASSE RABENSTEIN LINO SCHMID ANDREAS BAUDER MELCHIOR GRAB PHILIPP SCHAER HANSRUEDI MAURER Glacier bed surveying with helicopter-borne dual-polarization ground-penetrating radar Journal of Glaciology glacier geophysics ground-penetrating radar ice thickness measurements mountain glaciers radio-echo sounding |
| title | Glacier bed surveying with helicopter-borne dual-polarization ground-penetrating radar |
| title_full | Glacier bed surveying with helicopter-borne dual-polarization ground-penetrating radar |
| title_fullStr | Glacier bed surveying with helicopter-borne dual-polarization ground-penetrating radar |
| title_full_unstemmed | Glacier bed surveying with helicopter-borne dual-polarization ground-penetrating radar |
| title_short | Glacier bed surveying with helicopter-borne dual-polarization ground-penetrating radar |
| title_sort | glacier bed surveying with helicopter borne dual polarization ground penetrating radar |
| topic | glacier geophysics ground-penetrating radar ice thickness measurements mountain glaciers radio-echo sounding |
| url | https://www.cambridge.org/core/product/identifier/S0022143018000990/type/journal_article |
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