Narrow-Band Sonar Signals of Small Cetaceans
The sonar signals of some of the smallest cetaceans are very similar to each other and very different than that of mid-sized cetaceans. Signals of Cephalorhynchus hectori, Cephalorhynchus commersonii (genus Cephalorhynchus), Phocoena phocoena, Neophocoena phocoena and Phocoenoides dalli (family phoc...
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ftdtic:ADA248359 2023-05-15T16:00:30+02:00 Narrow-Band Sonar Signals of Small Cetaceans Au, Whitlow W. NAVAL COMMAND CONTROL AND OCEAN SURVEILLANCE CENTER RDT AND E DIV SAN DIEGO CA 1991-12 text/html http://www.dtic.mil/docs/citations/ADA248359 http://oai.dtic.mil/oai/oai?&verb=getRecord&metadataPrefix=html&identifier=ADA248359 en eng http://www.dtic.mil/docs/citations/ADA248359 Approved for public release; distribution is unlimited. DTIC AND NTIS Biology *MARINE BIOLOGY *SONAR SIGNALS RESOLUTION PULSES SIGNALS PRESSURE BAYS ANIMALS BANDWIDTH SONAR HAWAII ENERGY ACOUSTICS CETACEANS REPRINTS PE62435N WUDN688674 Text 1991 ftdtic 2016-02-22T16:45:37Z The sonar signals of some of the smallest cetaceans are very similar to each other and very different than that of mid-sized cetaceans. Signals of Cephalorhynchus hectori, Cephalorhynchus commersonii (genus Cephalorhynchus), Phocoena phocoena, Neophocoena phocoena and Phocoenoides dalli (family phocoenidae) are compared with those of some larger dolphins. Signals of Tursiops truncatus, Delphinapterus leucas and Pseudorca crassidens, housed in Kaneohe Bay, Oahu, Hawaii, have peak frequencies between 100-200 kHz, with high amplitudes (210-225 dB re 1 microPa), short durations (50-70 micro s), and wide bandwidths (30-40 kHz). Some of the smaller cetaceans emit signals having peak frequencies between 120 and 140 kHz, with low amplitudes (< 170 dB re 1 microPa) , long durations (170-430 micro s) and narrow bandwidths (7-11 kHz). Double pulses are also emitted regularly by some of the smaller dolphins and very infrequently by the larger dolphins. Signals used by the smaller animals may reflect constraints associated with their small size and differences in generation mechanisms. For a given peak acoustic pressure, there is 3 to 4 times more energy in the signals of the smaller cetaceans. However, because of the narrower bandwidths, the distance resolution capability of the small cetacean signals is between 2 to 3.5 times inferior to that of the larger animals. Furthermore, the narrow bandwidth signals do not possess any doppler resolution properties. Marine biosystems, Marine biology. Published in the program of the Biennial Conference on the Biology of Marine Mammals (9th), held in Chicago, IL on 5-9 December 1991. Text Delphinapterus leucas Phocoena phocoena Defense Technical Information Center: DTIC Technical Reports database |
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Defense Technical Information Center: DTIC Technical Reports database |
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ftdtic |
language |
English |
topic |
Biology *MARINE BIOLOGY *SONAR SIGNALS RESOLUTION PULSES SIGNALS PRESSURE BAYS ANIMALS BANDWIDTH SONAR HAWAII ENERGY ACOUSTICS CETACEANS REPRINTS PE62435N WUDN688674 |
spellingShingle |
Biology *MARINE BIOLOGY *SONAR SIGNALS RESOLUTION PULSES SIGNALS PRESSURE BAYS ANIMALS BANDWIDTH SONAR HAWAII ENERGY ACOUSTICS CETACEANS REPRINTS PE62435N WUDN688674 Au, Whitlow W. Narrow-Band Sonar Signals of Small Cetaceans |
topic_facet |
Biology *MARINE BIOLOGY *SONAR SIGNALS RESOLUTION PULSES SIGNALS PRESSURE BAYS ANIMALS BANDWIDTH SONAR HAWAII ENERGY ACOUSTICS CETACEANS REPRINTS PE62435N WUDN688674 |
description |
The sonar signals of some of the smallest cetaceans are very similar to each other and very different than that of mid-sized cetaceans. Signals of Cephalorhynchus hectori, Cephalorhynchus commersonii (genus Cephalorhynchus), Phocoena phocoena, Neophocoena phocoena and Phocoenoides dalli (family phocoenidae) are compared with those of some larger dolphins. Signals of Tursiops truncatus, Delphinapterus leucas and Pseudorca crassidens, housed in Kaneohe Bay, Oahu, Hawaii, have peak frequencies between 100-200 kHz, with high amplitudes (210-225 dB re 1 microPa), short durations (50-70 micro s), and wide bandwidths (30-40 kHz). Some of the smaller cetaceans emit signals having peak frequencies between 120 and 140 kHz, with low amplitudes (< 170 dB re 1 microPa) , long durations (170-430 micro s) and narrow bandwidths (7-11 kHz). Double pulses are also emitted regularly by some of the smaller dolphins and very infrequently by the larger dolphins. Signals used by the smaller animals may reflect constraints associated with their small size and differences in generation mechanisms. For a given peak acoustic pressure, there is 3 to 4 times more energy in the signals of the smaller cetaceans. However, because of the narrower bandwidths, the distance resolution capability of the small cetacean signals is between 2 to 3.5 times inferior to that of the larger animals. Furthermore, the narrow bandwidth signals do not possess any doppler resolution properties. Marine biosystems, Marine biology. Published in the program of the Biennial Conference on the Biology of Marine Mammals (9th), held in Chicago, IL on 5-9 December 1991. |
author2 |
NAVAL COMMAND CONTROL AND OCEAN SURVEILLANCE CENTER RDT AND E DIV SAN DIEGO CA |
format |
Text |
author |
Au, Whitlow W. |
author_facet |
Au, Whitlow W. |
author_sort |
Au, Whitlow W. |
title |
Narrow-Band Sonar Signals of Small Cetaceans |
title_short |
Narrow-Band Sonar Signals of Small Cetaceans |
title_full |
Narrow-Band Sonar Signals of Small Cetaceans |
title_fullStr |
Narrow-Band Sonar Signals of Small Cetaceans |
title_full_unstemmed |
Narrow-Band Sonar Signals of Small Cetaceans |
title_sort |
narrow-band sonar signals of small cetaceans |
publishDate |
1991 |
url |
http://www.dtic.mil/docs/citations/ADA248359 http://oai.dtic.mil/oai/oai?&verb=getRecord&metadataPrefix=html&identifier=ADA248359 |
genre |
Delphinapterus leucas Phocoena phocoena |
genre_facet |
Delphinapterus leucas Phocoena phocoena |
op_source |
DTIC AND NTIS |
op_relation |
http://www.dtic.mil/docs/citations/ADA248359 |
op_rights |
Approved for public release; distribution is unlimited. |
_version_ |
1766396490030252032 |