Type |
Article |
Date |
2018-06 |
Language |
English |
Author(s) |
Eleftherakis Dimitrios1, Berger Laurent1, Le Bouffant Naig1, Pacault Anne1, Augustin Jean-Marie1, Lurton Xavier1 |
Affiliation(s) |
1 : Inst Francais Rech Exploitat Mer Ifremer, DFO NSE ASTI, Underwater Acoust Lab, CS 10070, F-29280 Plouzane, France. |
Source |
Marine Geophysical Research (0025-3235) (Springer), 2018-06 , Vol. 39 , N. 1-2 , P. 55-73 |
DOI |
10.1007/s11001-018-9348-5 |
WOS© Times Cited |
25 |
Keyword(s) |
Calibration, Seafloor backscatter, Multibeam echosounder, Single-beam echosounder |
Abstract |
The calibration of multibeam echosounders for backscatter measurements can be conducted efficiently and accurately using data from surveys over a reference natural area, implying appropriate measurements of the local absolute values of backscatter. Such a shallow area (20-m mean depth) has been defined and qualified in the Bay of Brest (France), and chosen as a reference area for multibeam systems operating at 200 and 300 kHz. The absolute reflectivity over the area was measured using a calibrated single-beam fishery echosounder (Simrad EK60) tilted at incidence angles varying between 0° and 60° with a step of 3°. This reference backscatter level is then compared to the average backscatter values obtained by a multibeam echosounder (here a Kongsberg EM 2040-D) at a close frequency and measured as a function of angle; the difference gives the angular bias applicable to the multibeam system for recorded level calibration. The method is validated by checking the single- and multibeam data obtained on other areas with sediment types different from the reference area. |
Full Text |
File |
Pages |
Size |
Access |
|
19 |
3 MB |
Access on demand |
Author's final draft |
52 |
3 MB |
Open access |
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