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The Barny program: fourteen years of NURC-NRL collaboration
(NURC, 2009/05)
Shallow ocean environments, with their rapid variability, short spatial scales and often intense fishing, pose a special challenge for physical oceanographic study. Since 1995, a series of collaborative programs between ...
Source localization in shallow water using multi-frequency processing of shot data
(NATO. SACLANTCEN, 1996/07)
Multi-frequency processing methods are applied to real data generated by explosives to examine the
Performance assessment of propagation models in AESS-6.0
(NATO. SACLANTCEN, 1999/08)
A set of AESS propagation-loss predictions has been generated for typical operational scenarios in both deep and shallow water, for two sonar frequencies (500 and 3500 Hz) and for several source-receiver combinations. ...
Statistical normalization of non-Rayleigh reverberation
(NATO. SACLANTCEN, 2000/02)
Low-frequency active sonar systems operating in shallow water are primarily limited by reverberation.
Deployable underwater surveillance systems: analysis of experimental results: part III
(NATO. SACLANTCEN, 1999/04)
Deployable Underwater Surveillance Systems (DUSS) are a new active sonar concept based on a distributed network of small multistatic transmitter / receiver nodes. This study analyzes data acquired during the period 29 June ...
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 ...
High-resolution characterization of shallow water sea bottom: need and methodology for a ground-truth reference database
(NATO. SACLANTCEN, 1994/12)
A systematic approach to underwater observation of high-resolution seabed features has been developed. These include: morphology caused by current, wave, and biological factors and certain engineering geological factors ...
Impact of uncertain environmental knowledge on the shallow-water transfer function
(NATO. SACLANTCEN, 1992/12)
It is assumed that the acoustic channel can be modeled as a linear time-invariant space-variant filter. In this case, from linear systems theory, it is known that the filter output, that is the predicted source signal ...
An acoustic, high resolution, sediment profiler
(NATO. SACLANTCEN, 1966/11)
An acoustic sediment profiler is described that utilizes short 50 kHz pulses to achieve a high range resolution. In trials in shallow water, penetration depths of about 9 m and resolution of about 25 cm were obtained. ...
Horizontal array gain in shallow water
(NATO. SACLANTCEN, 1980/12)
Some results of a comprehensive model study on the use of horizontal hydrophone arrays in shallow water are presented. Well-known signal processing techniques are applied to a shallow-water sound propagation model in order ...