| The New Age of Scientific Partnerships: Acoustic Capabilities and Facilities at NUWC Division, Newport -- Surface ASW Directorate Outlook |
29 SEP 94 |
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| Authors:
Peter D. Herstein; Joseph M. Monti; David G. Browning; NAVAL UNDERSEA WARFARE CENTER NEWPORT DIV RI
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| Sensitivity of Shallow Water Transmission Loss to Source and Receiver Proximity to a Hard Bottom Under Downward Refracting Conditions |
16 DEC 93 |
17 pages |
| Authors:
Peter D. Herstein; Bernard F. Cole; David G. Browning; William G. Kanabis; NAVAL UNDERSEA WARFARE CENTER NEWPORT DIV RI
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 | Under downward refracting conditions, raypaths from a shallow source will tend to have grazing angles at a hard bottom that are greater than the critical angle arid, therefore, suffer a relatively large loss per bounce . As the source depth increases, lower grazing angles can be obtained. When the grazing angle becomes less than the critical angle, bottom loss per bounce is significantly reduced, allowing a possible reduction in propagation ... |
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| NUWC Shallow Water Curtain Effect with Biot Bottom Loss: System Impact |
25 OCT 93 |
14 pages |
| Authors:
David G. Browning; Raymond J. Christian; Peter D. Herstein; Joseph M. Monti; NAVAL UNDERSEA WARFARE CENTER NEWPORT DIV NEW LONDON CT NEW LONDON DETACHMENT
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| The Curtain Effect was originally conceived to compare the relative rates of loss of spreading and attenuation in deep water in order to estimate possible attainable acoustic detection ranges. It was later modified to compare spreading, attenuation, and bottom loss in shallow water for the same purpose (NUWC-NL Technical Document 4009, 2 March 1992). We now compare the Shallow Water Curtain under strongly downward refracting conditions for various source/ receiver ... |
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| A Study of Low Frequency Sound Propagation in Shallow Water Ducts |
14 FEB 92 |
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| Authors:
Joseph M. Monti; Jeffrey H. Sammis; David G. Browning; Peter D. Herstein; NAVAL UNDERSEA WARFARE CENTER NEW LONDON CT NEW LONDON DETACHMENT
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 | This paper presents results from a recent investigation of shallow water propagation loss for low frequencies (500-4000 Hz). Shallow water is defined in this context as a location where acoustic energy has numerous boundary interactions. This definition leads to both physically shallow and not- so-shallow sites. The objectives of this investigation are, first, to gain a quantitative understanding of propagation loss as a function of source/receiver placement and frequency for ... |
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| The Effect of Noisy Reflection Data on an Inverse Method for Determining the Structure of a Layered Ocean Bottom |
18 JUL 1983 |
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| Authors:
David J. Thomson; Peter D. Herstein; NAVAL UNDERWATER SYSTEMS CENTER NEW LONDON CT NEW LONDON LAB
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| A basic inverse problem in underwater acoustics is the determination of the structure of the sea bed from a limited knowledge of its reflection coefficient. For many applications, an adequate model for studying the acoustic interaction is provided by the scattering of plane waves by a layered liquid medium. In contrast to formally exact solutions to this inverse scattering problem, Candel, et al., (J. Sound Vib. 68, 571-595 (1980)) developed ... |
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| Coefficient of Variation Spectral Analysis: An Application to Underwater Acoustics |
03 MAY 1983 |
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| Authors:
Peter D. Herstein; Robert F. LaPlante; NAVAL UNDERWATER SYSTEMS CENTER NEW LONDON CT NEW LONDON LAB
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| Acoustic noise in the ocean is often described in terms of its power spectral density. Just as in other media, this noise consists of both narrowband and broadband frequency components. A major problem in the analysis of power spectral density measurements is distinguishing between narrowband spectral components of interest and contaminating narrowband components. In this paper, the use of coefficient of variation (Cv) spectrum is examined as an adjunct to ... |
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| Studies on the Interaction of Low-Frequency Acoustic Signals with the Ocean Bottom |
DEC 1979 |
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| Authors:
Salvatore R. Santaniello; Frederick R. DiNapoli; Robert K. Dullea; Peter D. Herstein; NAVAL UNDERWATER SYSTEMS CENTER NEW LONDON CT NEW LONDON LAB
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| Understanding the mechanisms by which the ocean sediment redirects impinging sound back into the ocean is necessary in developing propagation models for sonar performance prediction. The Naval Underwater Systems Center (NUSC) has (1) conducted controlled, self-calibrating acoustic measurements where the ocean bottom interacted signal is isolated in time for analysis, (2) developed deconvolution processing techniques to aid in describing the impulse response of the ocean sediment, and (3) performed modeling ... |
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| A Synopsis of Studies on the Interaction of Low Frequency Acoustic Signals with the Ocean Bottom. |
30 JUN 1976 |
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| Authors:
Salvatore R. Santaniello; Frederick R. DiNapoli; Robert K. Dullea; Peter D. Herstein; NAVAL UNDERWATER SYSTEMS CENTER NEW LONDON CONN NEW LONDON LAB
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| Understanding the mechanisms by which the ocean sediment redirects impinging sound back into the ocean is necessary in developing propagation models for SONAR performance prediction. Thus, NUSC has (1) conducted controlled, self-calibrating acoustic measurements where the bottom interacted signal is isolated in time for analysis, (2) developed deconvolution processing techniques to aid in describing the impulse response of the ocean sediment and (3) performed modeling to study the interaction of ... |
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| The Effect of Noise on the Deconvolution of Ocean Sediment Interacted Acoustic Signals. |
11 JUN 1976 |
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| Authors:
Peter D. Herstein; NAVAL UNDERWATER SYSTEMS CENTER NEW LONDON CONN NEW LONDON LAB
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| The waveform resulting from transient acoustic signal interaction with the ocean sediment can be extremely complex. Deconvolution can be used to obtain the sediment's acoustic impulse response, which can improve the ability to infer sediment acoustic properties. The process is performed by computing the Inverse Fourier Transform of the transfer function, which is the quotient of the sediment interacted signal's complex spectrum divided by the incident source signal's complex spectrum. ... |
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