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Resonance scattering analysis by autoregressive models applied to air-filled, cylindrical, thin walled shells in water
(NATO. SACLANTCEN, 1997/10)
Autoregressive (AR) parametric spectral estimation of the scatterer transfer function is applied to the analysis of acoustic scattering by elastic objects. In accordance with Resonance Scattering Theory (RST), the specular ...
Resonance analysis of the acoustic response of a water-filled cylindrical shell
(NATO. SACLANTCEN, 1998/09)
The resonance analysis approach developed for characterizing free-field air-filled cylindrical shells in terms of geometrical and mechanical pararneters is extended to fluid-filled shells either in the freefield or proud ...
RAPID RESPONSE, september 1996: modelling of broadband transmission loss along selected tracks in the Strait of Sicily
(NATO. SACLANTCEN, 1997/07)
A large set of experimental acoustic broadband data in the 50-3200 Hz band is analyzed with the objective of deriving average geoacoustic models for three sites in the Strait of Sicily. The experimental data were obtained ...
Toeplitz constrained adaptive beamforming with auxiliary data
(NATO. SACLANTCEN, 1997/02)
Submarine and mine detection using active sonar face similar problems when adaptive beamforming is required to provide high angular resolution or to suppress angularly isolated interferences. Both
Modeling non-Rayleigh reverberation
(NATO. SACLANTCEN, 1997/05)
Researchers over the past three decades have experimentally examined non-Rayleigh reverberation,
A towed CTD chain for two-dimensional high resolution hydrography
(NATO. SACLANTCEN, 1997/04)
The need for accurate two-dimensional datasets of temperature and salinity in the upper ocean led to the development of a new type of towed chain. Low-cost sensors are moulded in fins and may be randomly placed on the tow ...
Channel sensitive processor: real data processing
(NATO. SACLANTCEN, 1998/02)
The CSP is applied to data collected during the DUSS97 sea trial. A one-way geometry is used and the transmitted signal propagation time is known a priori. As predicted by analytical and simulation studies, the CSP detector ...
A parametric synthetic aperure sonar for detection of proud and buried mines
(NATO. SACLANTCEN, 1997/12)
This paper describes an experimental comparison between a parametric sonar and a conventional sonar for the detection of small objects on and in, the sea bed. Two experiments were performed in France (GESMA site) in October ...
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 ...
Deployable underwater surveillance systems(DUSS): localization and fusion of multistatic contacts: evaluation of feasibility using experimental data
(NATO. SACLANTCEN, 1998/12)
Active sonar deployable underwater surveillance systems (DUSS) are based on a distributed network