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The Journal of the Acoustical Society of America, 2001
Ambient Noise (AN) research during World War II was facilitated by the availability of calibrated instruments and motivated by the necessity to understand AN levels in coastal waters. The state-of-the-art was reviewed by Knudsen in 1948 and later by Pryce and Urick in 1954.
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Ambient Noise (AN) research during World War II was facilitated by the availability of calibrated instruments and motivated by the necessity to understand AN levels in coastal waters. The state-of-the-art was reviewed by Knudsen in 1948 and later by Pryce and Urick in 1954.
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Ambient noise in large rivers (L)
The Journal of the Acoustical Society of America, 2011This paper presents the results of hydroacoustic noise research in three large European rivers: the Danube, the Sava, and the Tisa. Noise in these rivers was observed during a period of ten years, which includes all annual variation in hydrological and meteorological conditions (flow rate, speed of flow, wind speed, etc.).
Miodrag S, Vračar, Miomir, Mijić
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Ambient Noise: Characteristics of the Noise Field
1985The variability of the wind- and traffic-generated ambient noise related to source field and transmission path is discussed with emphasis on shallow water where the small noise intercept ranges allow controlled experiments.
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Spatial filtering in ambient noise interferometry
The Journal of the Acoustical Society of America, 2014Theoretically, the empirical Green's function between a pair of receivers can be extracted from the cross correlation of the received diffuse noise. The diffuse noise condition rarely is met in the ocean and directional sources may bias the Green's function.
Olivier, Carrière +2 more
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Ambient noise data logger buoy
IEEE Journal of Oceanic Engineering, 1990A buoy for measuring wind speed and the ambient noise sound pressure level from 10 to 1500 Hz with 1-Hz resolution is described. The measurement buoy was deployed in a remote fjord in southeastern Alaska from October to December, 1989. The results from the data collected show that, for a wind speed of 5 kn, the measured ambient noise level at 900 Hz ...
D.E. Hollinberger, D.W. Bruder
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GEOACOUSTIC INVERSION OF AMBIENT NOISE: A SIMPLE METHOD
Acoustical Oceanography 2001, 2002The vertical directionality of ambient noise is strongly influenced by seabed reflections. Therefore, potentially, geoacoustic parameters can be inferred by inversion of the noise. In this approach, using vertical array measurements, the reflection loss is found directly by comparing the upward- with the downward-going noise.
Harrison, C.H., Simons, D.G.
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A harmonic noise model for direction finding in colored ambient noise
IEEE Signal Processing Letters, 1995High-resolution algorithms for direction finding of narrowband sources require a good estimate of the noise correlation matrix. We derive a physically motivated linear noise model. It is based on a Fourier expansion of the ambient noise field and is applicable to arbitrary antenna arrays. We also show that for contrived cases, a linear model may not be
Filiep Vanpoucke, Arogyaswami Paulraj
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Speech Communications as Limited by Ambient Noise
The Journal of the Acoustical Society of America, 1964Speech-intelligibility scores as a function of noise level are studied for face-to-face, sound-powered-phone, and amplified speech (earphone and loudspeaker) communication conditions. The speech-interference level (SIL) for octaves of noise centered at 500, 1000, and 2000 cps (0.5/1/2) is used as the measure of noise level. By using this noise measure,
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Target detection and location with ambient noise
The Journal of the Acoustical Society of America, 2008By placing a vertical array in an ambient noise field and forming an upward and a downward beam one obtains two time series which can be cross correlated to reveal a subbottom profile of the seabed [Siderius et al., J. Acoust. Soc. Am. 120, 1315–1323 (2006)]. Here the cross-correlation approach is applied to the location in range and bearing of a point
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Robustness and constraints of ambient noise inversion
The Journal of the Acoustical Society of America, 2008One of the most dominant sources of error in the estimation of sonar performance in shallow water is the geoacoustic description of the sea floor. As reviewed in this paper, various investigators have studied the possible use of ambient noise to infer some key parameters such as the critical angle, geoacoustic properties, or bottom loss.
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