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Acoustic impact of upper ocean models
(NATO. SACLANTCEN, 1989/12)
The upper mixed-surface layer of the ocean, with its homogeneous vertical temperature profile, provides a somewhat special acoustic propagation environment where the sound speed will increase (due to pressure) down to the ...
Numerical simulation of the effects of bathymetry on underwater sound propagation using three-dimensional parabolic models
(NATO. SACLANTCEN, 1998/03)
Two different three-dimensional parabolic equation (PE) methods are
Observed sound velocity and temperature profiles in the Strait of Gibraltar during the passage of an internal wave
(NATO. SACLANTCEN, 1966/10)
Sound velocity and temperature measurements taken from the sea-surface to 350 m depth, close to one spot over a 24-hour period revealed the passage of an internal wave of approximately 60 m amplitude. The effect of this ...
Reverberation suppression
(NATO. SACLANTCEN, 1995/05)
We propose a processing methodology for shallow-water reverberation
The effect of a layer of varying density on high-frequency acoustic reflection, forward propagation loss and backscattering strength
(NATO. SACLANTCEN, 1997/06)
This report examines the impact that a thin layer of varying density would have on high-frequency reflection, forward loss and backscattering of acoustic plane waves from the seafloor. A functional form for density ...
Time series variability in fluctuating ocean waveguides
(NATO. SACLANTCEN, 1999/07)
The variability of signals propagating through an uncertain sound speed structure is addressed. Signals are assumed to travel in a narrow band adiabatically in modes and to experience fluctuations in sound speed which are ...
Broadband acoustic transmission intensity fluctuations in the Tyrrhenian Sea
(NATO. SACLANTCEN, 1996/11)
An acoustic propagation experiment was carried out in the Tyrrhenian Sea in October 1985 in which signals from a broadband source were recorded at a range of 5 km with a vertical 62 m hydrophone array over a period of 5 ...
SUPREMO: a multistatic sonar performance model
(NATO. SACLANTCEN, 2002/11)
Multistatic sonars introduce new problems to the modeller such as mutual interference from multiple sources and variable target aspect in a background of range-dependent bistatic reverberation. A multistatic sonar performance ...