Technical Reports: Recent submissions
Now showing items 261-280 of 322
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Limitations on towed array gain imposed by a non-isotropic ocean
(NATO. SACLANTCEN, 1990/08)This study deals with the limitations imposed by ocean characteristics on hydrophone array gain and on attempts to create a synthetic aperture using towed-array measurements. The multi-element synthetic or physical aperture ... -
Development of barotropic models for the GIN Sea
(NATO. SACLANTCEN, 1991/03)Barotropic ocean models are developed for deep oceans, with arbitrary topography and basin geometry, on a sphere. A special adaptation is made for the Greenland-Iceland-Norwegian (GIN) Seas with closed lateral boundaries. ... -
Model statistics of inertial shear from multi- year simulations at weathership 'Mike': currents, atmospheric forcing, internal waves, mixed layer, Norwegian Sea)
(NATO. SACLANTCEN, 1990/12)In this memorandum we focus on one of the most important environmental -
Oceanographic analysis of NAPOLI'85, an experiment in the Tyrrhenian Sea
(NATO. SACLANTCEN, 1990/03)In 1985, an acoustic/oceanographic experiment (NAPOLI '85) was carried out in the Tyrrhenian Sea to investigate acoustic propagation -
Target detection using a three-layered neural network trained by supervised back-propagation
(NATO. SACLANTCEN, 1990/05)In any sonar system a detection process has to be performed at -
Atlantic inflow experiment, GIN Sea Cruise'86: Data report Part II: circulation
(NATO. SACLANTCEN, 1990/03)As the initial field effort of the Atlantic Inflow Experiment, three instrumented moorings were deployed in the Faeroe-Shetland Channel during June 1986. The purpose of the array was to monitor the inflow, and to tract the ... -
Interface-wave propagation studies: an example of seismo-acoustic propagation in non-homogeneous materials
(NATO. SACLANTCEN, 1990/01)This study addresses the problem relating to the interaction processes -
Upper layer environmental parameters from CTD data - GIN '86 cruise
(NATO. SACLANTCEN, 1989/12)The data from the SACLANTCEN June 1986 Cruise is analysed -
Acoustic impact of upper ocean models
(NATO. SACLANTCEN, 1989/12)The upper mixed-surface layer of the ocean, with its homogeneous vertical temperature profile, provides a somewhat special acoustic propagation environment where the sound speed will increase (due to pressure) down to the ... -
Analysis of basin backscattering in the Levantine Sea
(NATO. SACLANTCEN, 1989/12)Research has been conducted in the Levantine Sea basin to measure low-frequency basin reverberation and relate the measurements to backscattering strength. The receivers were a towed horizontal array and a suspended vertical ... -
Delay-Doppler resolution performance of large time-bandwidth product linear FM signals in a multi- path ocean environment
(NATO. SACLANTCEN, 1989/04)Active sonar systems that transmit large time-bandwidth (TW)-product linear frequency modulated (LFM) waveforms and receive echoes from targets of unknow~r~an ge and speed can suffer considerable correlation losses that ... -
The effect of thermohaline variability on the exchange through Mediterranean straits
(NATO. SACLANTCEN, 1989/05)exchanges through straits. The primary assumption is that the exchange is determined by tlle pressure force created by the differing weights of tlle water columns on either side of the sill and by the continuity of mass ... -
Transmission-time variability, vertical spatial and temporal analysis of NAPOLI'85, an experiment in the Tyrrhenian Sea
(NATO. SACLANTCEN, 1989/09)An acoustic propagation experiment (NAPOLI '85) was carried out in the Tyrrhenian Sea in October 1985 in which signals from a broadband source were recorded at a range of 5 km with a vertical 62-m hydrophone array over a ... -
Pre-design operational requirements for underwater drones
(NATO. SACLANTCEN, 1989/11)The purpose of this report, prepared at the behest of Panel 7 of the Defence Research Group at NATO headquarters in Brussels, is to list -
A note on attenuation and dispersion in marine sediments
(NATO. SACLANTCEN, 1989/04)From the more recent investigations reported ill the literature, -
Test and evaluation of objective mapping applied to oceanographic data from GIN Sea'86
(NATO. SACLANTCEN, 1989/03)This study is an investigation to produce an objective analysis -
An autonomous undersea surveillance vehicle: concept and operational feasibility
(NATO. SACLANTCEN, 1988/12)The concept of autonomous undersea vehicles (AUVs) is becoming feasible through the increasing practicality of artificial intelligence, decreasing size and cost of computers, and improved technical capabilities. This paper ... -
Extended towed-array processor by overlapped correlator
(NATO. SACLANTCEN, 1988/11)The development of an algorithm for extended towed-array measurements, which could be used by matched-field estimators to obtain information about depth and range of a source, is studied. This algorithm combines coherently ... -
Mixed layer deepening and variability in the upperlayers if the central western Mediterranean, MILEX-82: final report
(NATO. SACLANTCEN, 1988/10)The 1982 Mixed-Layer Experiment (MILEX-82) is described in detail and the data are presented in ways designed to illustrate the spatial and temporal variability of the surface and deeper layers of the central western ... -
Analysis systems for the mesoscale thermal variability in the Greenland-Iceland-Norwegian Sea
(NATO. SACLANTCEN, 1988/07)Mesoscale thermal structure and its spatial variability are very significant for acoustic propagation in the ocean. Therefore ocean thermal analysis procedures are important for the initialisation andverification of ...