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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 ...
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 ...
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 ...
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 ...
A classification technique combining aspect dependence and elastic properties of target scattering
(NATO. SACLANTCEN, 1999/04)
Discrimination between man-made and natural underwater objects and between man-made objects of different characteristics are the key objectives of target classication. The current approach is mainly based on the analysis ...
Detection of buried objects at low grazing angles: preliminary experimental results
(NATO. SACLANTCEN, 1998/06)
This report considers the acoustic detection of objects buried in the seabed, and especially the possibility of using subcritical insonification geometries in order to increase coverage rate.
The application of parametric side scan sonar to the detection of proud and buried targets
(NATO. SACLANTCEN, 1998/01)
This paper describes an experiment designed to evaluate the feasibility of using the TOPAS parametric transmitter mounted in side scan mode, for the detection of buried targets. The concept was tested with proud targets ...
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 ...
Modelling of scattering by objects on the seabed
(NATO. SACLANTCEN, 1997/12)
This paper describes some of the theory and implementation issues of modeling the backscattered