Browsing Technical Reports by Title
Now showing items 200-219 of 322
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Oceanographic data from the southern Tyrrhenian Sea: August to October 1984: Part 1 - Floats and moored instruments: Part 2 - Hydrography
(NATO. SACLANTCEN, 1988/02)A SACLANTCEN observational programme in the Southern Tyrrhenian Sea comprised a sequence of three cruises during the period August to November 1984. The primary purpose was to investigate the late summer water-mass variability ... -
Oceanographic measurements of the West Black Sea: November 26 to December 14, 1995
(NATO. SACLANTCEN, 1998/06)Mediterranean water inflow into the Black Sea is investigated using acoustic and oceanographic data obtained in the Black Sea exit region. Temporal and spatial variability in the flow and their relation to atmospheric and ... -
Oceanography of the Strait of Sicily: proceedings of a conference held at SACLANTCEN on 11-12 April 1972
(NATO. SACLANTCEN, 1972/09) -
On the applicability of satellite-borne SAR imagery to coastal oceanography
(NATO. SACLANTCEN, 1996/02)Synthetic aperture radar (SAR) images have been acquired from the first European Space Agency (ESA) remote sensing satellite ERS- 1. The mesoscale feature images are from Norwegian coastal waters and the Mediterranean (Elba ... -
On the predictability of subsurface sound speed from satellite-measured sea-surface temperature in the Mediterranean
(NATO. SACLANTCEN, 1996/01)The report investigates the extent to which subsurface sound speed may be determined from satellitemeasured -
On the recording of low frequency signals on magnetic tape
(NATO. SACLANTCEN, 1962/01)A short review of the different methods of recording on magnetic tape is given together with the advantages and disadvantages of each method. Particular emphasis was given to the ability to record low frequencies. This ... -
On the spatial variability of the impulse response of an underwater acoustic channel
(NATO. SACLANTCEN, 2000/05)In many applications like adaptive equalization, beam-forming, matched field processing or focalization the performance is limited due to changes in the impulse response caused by variations in source-receiver range or in ... -
Optimum bearing resolution for a moving towed array and extension of its physical aperture
(NATO. SACLANTCEN, 1989/04)This report examines the limits of the angular resolution capability of a moving towed array (MTA) by -
Parameter estimation using multi-frequency range-dependent acoustic data in shallow water
(NATO. SACLANTCEN, 1996/11)The estimation of all forward model parameters - geometric, geoacoustic, -
Parametric relations on FM sonar
(NATO. SACLANTCEN, 1961/06)The report deals with the simple theory of FM sonar operations and shows how an optimum system may be designed. It also indicates the effects of doppler, the equipment and other factors which may be expected, in practice, ... -
Passive acoustic detection of marine mammals
(NATO. SACLANTCEN, 2000/04)A passive acoustic analysis of data recorded during the SACLANTCEN -
Passive localization using propagation models
(NATO. SACLANTCEN, 1987/06)Passive ranging using propagation models can be effected in two different ways: forward modeling -
Passive ranging with the SNAP model: a performance study
(NATO. SACLANTCEN, 1987/07)A passive ranging technique which uses SNAP, the SACLANT Centre's normal-mode model, is studied. An examination is made of the sensitivity of the technique to errors in the assumed sound -
PC-based propagation and sonar prediction models
(NATO. SACLANTCEN, 1995/12)Six acoustic models available for use on PC's are tested on a series of typical propagation situations from the North Atlantic and the Mediterranean. The model set includes both early US Navy models (ASTRAL, FACT, RAYMODE) ... -
Penetration of acoustic waves into sandy seafloors at low grazing angles: the Helmholtz-Kirchhoff approach
(NATO. SACLANTCEN, 1998/08)The Helmholtz-Kirchhoff integral is applied to model the penetration of sound waves into sandy seafloors at grazing angles above and below the critical angle. Although the conditions for the validity -
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. ... -
Performance assessment of the LYBIN - 2.0 propagation-loss model
(NATO. SACLANTCEN, 2001/07)A new acoustic model LYBIN has been proposed for inclusion in the AESS model set. In order to determine this model's prediction accuracy and computational efficiency, SACLANTCEN was tasked to test LYBIN on exactly the same ... -
Performance assessment of the SACLANTCEN vertical array in shallow water
(NATO. SACLANTCEN, 1994/03)In this memoranduin the performance of the SACLANTCEN vertical -
Perturbation theory applied to sound scattering from a rough sea-floor
(NATO. SACLANTCEN, 1992/09)Perturbation theory is applied to acoustic scattering from a rough sedimental sea-floor. Realistic -
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 ...