Arctic ambient noise beamforming and modelling / by Michael Greening.: DR52-12/2-1989E-PDF
"The following report details the work completed to date in characterizing the transients contained in the acoustic noise produced from Arctic pack ice. A simple source detection system capable of finding transients with a high signal to noise ratio was used and an average and median number of transients of 4 and 2 respectively were found per 2-minute sample of data. These transients were shown to be vertically directional with a loss at 50-100Hz of approximately 15dB from 5 to 15 degrees from horizontal and a further loss of 10dB from 15 to 90 degrees. This vertical directivity was also shown to increase slightly with frequency. In examining bottom characteristics to aid in modelling the source propagation, sub-bottom layers at 3m and 15 m deep were found. Although exact measurements of bottom roughness were not obtained, it was observed to be acoustically flat for frequencies of up to 2000Hz."--abstract (page 1).
Permanent link to this Catalogue record:
publications.gc.ca/pub?id=9.936229&sl=0
| Department/Agency | JASCO Research Ltd., issuing body. Defence Research Establishment Pacific, issuing body. Canada. Department of National Defence. Research and Development Branch, issuing body. |
|---|---|
| Title | Arctic ambient noise beamforming and modelling / by Michael Greening. |
| Series title | Contractors report series ; 89-28 |
| Publication type | Series - View Master Record |
| Language | [English] |
| Format | Electronic |
| Electronic document | |
| Note(s) | "Contract Serial No: W7708-8-9910/01-SB"--title page. "Scientific Authority: Dr. P. Zakarauskas, Defence Research Establishment Pacific"--title page. Digitized edition from print [produced by Defence Research and Development Canada]. |
| Publishing information | Sidney, B.C. : JASCO Research Ltd., March 1989 |
| Author / Contributor | Greening, Michael Victor, 1961- author. |
| Description | 1 online resource (13 pages, 35 unnumbered pages) : illustrations, charts |
| Catalogue number |
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| Departmental catalogue number | CRS 89-28 |
| Subject terms | Ice -- Acoustic properties -- Arctic Ocean. Glace -- Propriétés acoustiques -- Arctique, Océan. |