A post-processing technique to remove background noise from echo integration data
Echo integration of biological organisms with a low target strength can be difficult because of the problem of setting suitable pre-integration thresholds, and this is particularly acute with higher frequencies, such as 120 or 200 kHz, which are often used in studies of euphausiids. One solution is...
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Oxford University Press
1996
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Online Access: | http://nora.nerc.ac.uk/id/eprint/515354/ https://doi.org/10.1006/jmsc.1996.0046 |
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ftnerc:oai:nora.nerc.ac.uk:515354 2023-05-15T16:08:28+02:00 A post-processing technique to remove background noise from echo integration data Watkins, Jonathan L. Brierley, Andrew S. 1996 http://nora.nerc.ac.uk/id/eprint/515354/ https://doi.org/10.1006/jmsc.1996.0046 unknown Oxford University Press Watkins, Jonathan L.; Brierley, Andrew S. 1996 A post-processing technique to remove background noise from echo integration data. ICES Journal of Marine Science, 53 (2). 339-344. https://doi.org/10.1006/jmsc.1996.0046 <https://doi.org/10.1006/jmsc.1996.0046> Publication - Article PeerReviewed 1996 ftnerc https://doi.org/10.1006/jmsc.1996.0046 2023-02-04T19:43:58Z Echo integration of biological organisms with a low target strength can be difficult because of the problem of setting suitable pre-integration thresholds, and this is particularly acute with higher frequencies, such as 120 or 200 kHz, which are often used in studies of euphausiids. One solution is to integrate data without any threshold and then remove background noise during post-processing. Unthresholded, integrated data of micronekton and Euphausia superba collected with a SIMRAD EK500 at frequencies of 38 and 120 kHz are presented. The underlying background noise level follows a 20 log R+2αR relationship, which can be scaled to the minimum volume backscatter (Sv) in each layer during a transect and then subtracted from the entire data set to remove background noise. The utility of this procedure is demonstrated by making comparisons of Sv at each frequency and investigating the effect of noise removal on the identification of targets based on the dB difference (120 kHz Sv–38 kHz Sv). Article in Journal/Newspaper Euphausia superba Natural Environment Research Council: NERC Open Research Archive ICES Journal of Marine Science 53 2 339 344 |
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Open Polar |
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Natural Environment Research Council: NERC Open Research Archive |
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ftnerc |
language |
unknown |
description |
Echo integration of biological organisms with a low target strength can be difficult because of the problem of setting suitable pre-integration thresholds, and this is particularly acute with higher frequencies, such as 120 or 200 kHz, which are often used in studies of euphausiids. One solution is to integrate data without any threshold and then remove background noise during post-processing. Unthresholded, integrated data of micronekton and Euphausia superba collected with a SIMRAD EK500 at frequencies of 38 and 120 kHz are presented. The underlying background noise level follows a 20 log R+2αR relationship, which can be scaled to the minimum volume backscatter (Sv) in each layer during a transect and then subtracted from the entire data set to remove background noise. The utility of this procedure is demonstrated by making comparisons of Sv at each frequency and investigating the effect of noise removal on the identification of targets based on the dB difference (120 kHz Sv–38 kHz Sv). |
format |
Article in Journal/Newspaper |
author |
Watkins, Jonathan L. Brierley, Andrew S. |
spellingShingle |
Watkins, Jonathan L. Brierley, Andrew S. A post-processing technique to remove background noise from echo integration data |
author_facet |
Watkins, Jonathan L. Brierley, Andrew S. |
author_sort |
Watkins, Jonathan L. |
title |
A post-processing technique to remove background noise from echo integration data |
title_short |
A post-processing technique to remove background noise from echo integration data |
title_full |
A post-processing technique to remove background noise from echo integration data |
title_fullStr |
A post-processing technique to remove background noise from echo integration data |
title_full_unstemmed |
A post-processing technique to remove background noise from echo integration data |
title_sort |
post-processing technique to remove background noise from echo integration data |
publisher |
Oxford University Press |
publishDate |
1996 |
url |
http://nora.nerc.ac.uk/id/eprint/515354/ https://doi.org/10.1006/jmsc.1996.0046 |
genre |
Euphausia superba |
genre_facet |
Euphausia superba |
op_relation |
Watkins, Jonathan L.; Brierley, Andrew S. 1996 A post-processing technique to remove background noise from echo integration data. ICES Journal of Marine Science, 53 (2). 339-344. https://doi.org/10.1006/jmsc.1996.0046 <https://doi.org/10.1006/jmsc.1996.0046> |
op_doi |
https://doi.org/10.1006/jmsc.1996.0046 |
container_title |
ICES Journal of Marine Science |
container_volume |
53 |
container_issue |
2 |
container_start_page |
339 |
op_container_end_page |
344 |
_version_ |
1766404515948396544 |