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Measurements and modelling of high-frequency acoustic scattering by a rough seafloor and sea surface
(NURC, 2009/12)
Acoustic scattering by a rough, possibly dynamic interface is experimentally studied by insonifying the seabed and the sea surface at high frequency at various incidentangles. A directional source working at 300 kHz was ...
Statistical evaluation of 80 kHz shallow-water seafloor reverberation
(NATO. SACLANTCEN, 1997)
In this work a comparison is presented between 80 kHz reverberation statistics obtained at shallow water sites around Sardinia and Sicily. The data include measurements from several distinct bottom provinces, including ...
Ocean-basin reverberation from large underwater explosions: part 2: computer model for reverberation
(NATO. SACLANTCEN, 1975/10)
Following detonation of an underwater explosion, sound reverberates from the ocean surface and bottom and from scatterers within the medium. In addition, the boundaries of the ocean basin and obstructions within it, such ...
Modeling non-Rayleigh reverberation
(NATO. SACLANTCEN, 1997/05)
Researchers over the past three decades have experimentally examined non-Rayleigh reverberation,
Some comments on ray theory with examples from current NUC ray trace models
(NATO. SACLANTCEN, 1971/12)
Three topics were covered in this paper: 1. Ray Sweep-out Method - a technique for calculating sound intensities at a large number of receiver points in range and depth . 2. Bi-static Reverberation Model - a technique based ...
Statistical normalization of non-Rayleigh reverberation
(NATO. SACLANTCEN, 2000/02)
Low-frequency active sonar systems operating in shallow water are primarily limited by reverberation.
Statistical evaluation of 80 kHz shallow-water seafloor reverberation
(NATO. SACLANTCEN, 1997/09)
Knowledge of the background reverberation environment is a prerequisite for the design of any target detection scheme. While the problem of understanding and predicting high-frequency background reverberation level or mean ...
Multistatic bottom reverberation in shallow water
(NATO. SACLANTCEN, 1997)
A wavenumber integration approach to modeling of the full multistatic reverberant field produced by small-scale bottom roughness in stratified shallow water waveguides has been developed. A perturbation approach to rough ...
Acoustic characterization of a shallow water site
(NATO. SACLANTCEN, 1993/08)
Results are presented from an exercise aimed at providing a low frequency active sonar environmental characterization of a specific shallow water site in the Gulf of Mexico. Downward refracting acoustic transmission and ...
Sound absorption by suspended particulate matter
(NATO. SACLANTCEN, 1997)
A series of experiments has been performed to study the viscous absorption of sound by particulate suspensions typical of those found in coastal waters. The effect due to the particles in the frequency range of 50 - 150 ...