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Spectral integral representations of monostatic backscattering from three dimensional distributions of sediment volume inhomogeneities
(NATO. SACLANTCEN, 2001/03)
A theory is developed for generating short time, monostatic reverberation realizations caused by three dimensionally distributed volume inhomogeneities in stratified media. A spectral integral approach to treating the ...
Measurements of acoustic scattering from partially and completely buried spherical shells
(NATO. SACLANTCEN, 1999/04)
Recent work at NATO SACLANT Undersea Research Centre has concentrated on investigating the use of low frequency sonars (2-20 kHz) in order to better exploit scattering features of buried targets that can contribute to their ...
SAFARI Seismo-Acoustic Fast field Algorithm for Range-Independent environments: user's guide
(NATO. SACLANTCEN, 1988/09)
An efficient algorithm has been developed for solving the depth-separated wave equation in general fluid/solid horizontlly stratified media. The algorithm has been built into a general-purpose package of computer codes ...
Spectral integral representations of scattering from volume inhomogeneities
(NATO. SACLANTCEN, 1999/07)
In-situ measurements of scattering strength can be obtained by analyzing the early-time, high angle reverberation from bottom and sub-bottom features. In order to provide insight into the mechanisms which cause bottom ...
Efficient global matrix approach to the computation of synthetic seismograms
(NATO. SACLANTCEN, 1986/05)
A numerically efficient global matrix approach to the solution of the wave equation in horizontally stratified environments is presented. The field in each layer is expressed as a superposition of the field produced by the ...
Mechanisms for subcritical penetration into a sandy bottom: experimental and modelling results
(NATO. SACLANTCEN, 1998/05)
This paper presents the results of a recent study whose overall objectives are to determine the mechanism(s) contributing to subcritical acoustic penetration into ocean sediments, and to quantify the results for use in ...
Generic Oceanographic Array Technologies (GOATS)'98: bi-static seabed scattering measurements using autonomous underwater vehicles
(NATO. SACLANTCEN, 1998/10)
The GOATS'98 experiment was performed May 5-29, 1998 in shallow water off Marciana Marina, on the island of Elba, Italy. The experiment addressed some of the fundamental issues associated with using the new Autonomous Ocean ...
Physics of 3-D scattering from rippled seabeds and buried targets in shallow water
(NATO. SACLANTCEN, 1998/05)
The new OASES-3D code developed at MIT is used to investigate the spatial and temporal characteristics of reverberation from rippled seabeds insonified by narrow beam sonars such as the TOPAS parametric source. It is shown ...
Benchmarking of SCARAB volume scattering versus OASES volume scattering
(NATO. SACLANTCEN, 2001/05)
OASES uses wavenumber integration to solve for the backscattered pressure caused by sound speed and density inhomogeneity scatterers in the sediment; SCARAB uses a ray path technique to find the backscattered intensity. ...