Acoustic Phase Fluctuations Caused by Garrett-Munk Internal Waves.
Perturbed acoustic propagation is considered between a point source and an array receiver in which the perturbations are due to a Garrett-Munk internal wave field. The resultant acoustic phase fluctuations along the array are determined. Straight ray propagation is assumed, and three array orientati...
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ftdtic:ADA071354 2023-05-15T14:57:55+02:00 Acoustic Phase Fluctuations Caused by Garrett-Munk Internal Waves. Hughes,B DEFENCE RESEARCH ESTABLISHMENT PACIFIC VICTORIA (BRITISH COLUMBIA) 1979-03 text/html http://www.dtic.mil/docs/citations/ADA071354 http://oai.dtic.mil/oai/oai?&verb=getRecord&metadataPrefix=html&identifier=ADA071354 en eng http://www.dtic.mil/docs/citations/ADA071354 APPROVED FOR PUBLIC RELEASE DTIC AND NTIS Acoustics *SOUND TRANSMISSION *PERTURBATIONS *INTERNAL WAVES CANADA PHASE STUDIES VARIATIONS SCALING FACTOR ACOUSTIC ARRAYS SONAR SOUND ANALYZERS ACOUSTIC SIGNALS UNDERWATER SOUND Text 1979 ftdtic 2016-02-20T16:30:32Z Perturbed acoustic propagation is considered between a point source and an array receiver in which the perturbations are due to a Garrett-Munk internal wave field. The resultant acoustic phase fluctuations along the array are determined. Straight ray propagation is assumed, and three array orientations are considered: broadside horizontal, end fire horizontal and broadside vertical. It is shown that for an acoustic frequency of 150 Hz, a range of 50 km and a horizontal broadside receiver separation distance (in the array) of 1 km, the rms phase difference between the two receivers at 1000 m depth in the N. Pacific is typically 5 deg, and in the Arctic it is typically 2 deg, whereas in the N. Atlantic at the same depth it is typically 50 deg. These geographical variations are due mainly to variations in the potential sound velocity gradient. Similar phase differences occur for a vertical receiver separation of 50 m. The horizontal receiver separation necessary to reduce the acoustic coherence to 0.5 for the same operating conditions is shown to be very large in the N. Pacific (about = 400 km) and Arctic ( 1000 km), but only 2.3 km in the N. Atlantic. (Author) Text Arctic Defense Technical Information Center: DTIC Technical Reports database Arctic Canada Munk ENVELOPE(-95.993,-95.993,55.979,55.979) Pacific |
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Open Polar |
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Defense Technical Information Center: DTIC Technical Reports database |
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language |
English |
topic |
Acoustics *SOUND TRANSMISSION *PERTURBATIONS *INTERNAL WAVES CANADA PHASE STUDIES VARIATIONS SCALING FACTOR ACOUSTIC ARRAYS SONAR SOUND ANALYZERS ACOUSTIC SIGNALS UNDERWATER SOUND |
spellingShingle |
Acoustics *SOUND TRANSMISSION *PERTURBATIONS *INTERNAL WAVES CANADA PHASE STUDIES VARIATIONS SCALING FACTOR ACOUSTIC ARRAYS SONAR SOUND ANALYZERS ACOUSTIC SIGNALS UNDERWATER SOUND Hughes,B Acoustic Phase Fluctuations Caused by Garrett-Munk Internal Waves. |
topic_facet |
Acoustics *SOUND TRANSMISSION *PERTURBATIONS *INTERNAL WAVES CANADA PHASE STUDIES VARIATIONS SCALING FACTOR ACOUSTIC ARRAYS SONAR SOUND ANALYZERS ACOUSTIC SIGNALS UNDERWATER SOUND |
description |
Perturbed acoustic propagation is considered between a point source and an array receiver in which the perturbations are due to a Garrett-Munk internal wave field. The resultant acoustic phase fluctuations along the array are determined. Straight ray propagation is assumed, and three array orientations are considered: broadside horizontal, end fire horizontal and broadside vertical. It is shown that for an acoustic frequency of 150 Hz, a range of 50 km and a horizontal broadside receiver separation distance (in the array) of 1 km, the rms phase difference between the two receivers at 1000 m depth in the N. Pacific is typically 5 deg, and in the Arctic it is typically 2 deg, whereas in the N. Atlantic at the same depth it is typically 50 deg. These geographical variations are due mainly to variations in the potential sound velocity gradient. Similar phase differences occur for a vertical receiver separation of 50 m. The horizontal receiver separation necessary to reduce the acoustic coherence to 0.5 for the same operating conditions is shown to be very large in the N. Pacific (about = 400 km) and Arctic ( 1000 km), but only 2.3 km in the N. Atlantic. (Author) |
author2 |
DEFENCE RESEARCH ESTABLISHMENT PACIFIC VICTORIA (BRITISH COLUMBIA) |
format |
Text |
author |
Hughes,B |
author_facet |
Hughes,B |
author_sort |
Hughes,B |
title |
Acoustic Phase Fluctuations Caused by Garrett-Munk Internal Waves. |
title_short |
Acoustic Phase Fluctuations Caused by Garrett-Munk Internal Waves. |
title_full |
Acoustic Phase Fluctuations Caused by Garrett-Munk Internal Waves. |
title_fullStr |
Acoustic Phase Fluctuations Caused by Garrett-Munk Internal Waves. |
title_full_unstemmed |
Acoustic Phase Fluctuations Caused by Garrett-Munk Internal Waves. |
title_sort |
acoustic phase fluctuations caused by garrett-munk internal waves. |
publishDate |
1979 |
url |
http://www.dtic.mil/docs/citations/ADA071354 http://oai.dtic.mil/oai/oai?&verb=getRecord&metadataPrefix=html&identifier=ADA071354 |
long_lat |
ENVELOPE(-95.993,-95.993,55.979,55.979) |
geographic |
Arctic Canada Munk Pacific |
geographic_facet |
Arctic Canada Munk Pacific |
genre |
Arctic |
genre_facet |
Arctic |
op_source |
DTIC AND NTIS |
op_relation |
http://www.dtic.mil/docs/citations/ADA071354 |
op_rights |
APPROVED FOR PUBLIC RELEASE |
_version_ |
1766330013828775936 |