Browsing Technical Reports by Title
Now showing items 99-118 of 322
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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 ... -
Detection of buried mines using Rayleigh-scattered second-derivative Gaussian pulses
(NATO. SACLANTCEN, 1995/10)Large ground mines which are intentionally or unintentionally buried in the sediment have proven to -
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. -
Detection of buried objects in the seabed: a simple model study
(NATO. SACLANTCEN, 1998/10)The problem of detecting an object buried in the seabed is studied by means of a simple model. In this model, the object is a rigid sphere buried in a bottom modelled as a fluid half space. The scattered field is determined ... -
Detection of narrow-band low-level signals: simulated performance of high-resolution eigenstructure methods versus conventional beamforming
(NATO. SACLANTCEN, 1988/08)In this report the detection of narrow-band low-level signals by passive sonar is addressed, -
Detection of objects on a non Rayleigh background
(NATO. SACLANTCEN, 1995/12)Sector scanning sonar systems image the sea-bottom to detect objects that can be distinguished from the background structure of the seabottom. In current systems images are displayed and discarded as new image data become ... -
Development of a SACLANTCEN MCM sonar performance model
(NATO. SACLANTCEN, 1996/11)The report describes the Mine Countermeasures Sonar Performance -
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. ... -
Digital analysis working group: proceedings of a conference held at SACLANTCEN on 25-27 May 1971
(NATO. SACLANTCEN, 1972/05) -
Digital map and linked data (DMap) implementation at SACLANTCEN as an aid to sea-going research
(NATO. SACLANTCEN, 1995/08)DMaps (data maps), consisting of a geographical informatiorl system -
Direct observation of the angle of intromission in marine sediment
(NATO. SACLANTCEN, 2001/06)High porosity marine sediments like silty clays have the curious property that the speed of sound through its bulk medium is lower than that of the interstitial pore fluid. When a high porosity sediment is at the water ... -
Distortion of bottom reflected pulses
(NATO. SACLANTCEN, 1966/03)The theory of linear systems combined with numerical Fourier transformations and inversion is used to obtain the shape of a general pressure pulse after its reflection from a general multilayered sea floor. The method is ... -
Distributions of magnetic field variations, differences and residuals
(NATO. SACLANTCEN, 1999/02)Temporal and spatial variations of the geomagnetic field were recorded in different geographic areas, -
Drifter and float observations in the Adriatic Sea (1994-1996): data report
(NATO. SACLANTCEN, 1998/12)During the period December 1994 to November 1995, 62 Argos tracked surface drifters, one Argos tracked drifter drogued to 300 m and 3 Argos tracked sub-surface floats were released in the Adriatic Sea to describe the ... -
Drifter observations in the Nordic Seas (1991-1995) data report
(NATO. SACLANTCEN, 1996/02)During the period June 1991 to August 1993, 107 Argos tracked drifters drogued to 15 m depth were released in the Nordic seas (or Greenland-Iceland-Norwegian [GIN] sea) to study the variability of the near-surface circulation ... -
DUSS97: source localization and environmental inversion using vertical array data
(NATO. SACLANTCEN, 1998/08)Results on source localization and environmental inversion using experimental data acquired on a vertical line array are presented. Global inversion methods based on genetic algorithms are utilized to estimated the range ... -
Effects of intrinsic medium inhomogeneities on long-range acoustic transmission
(NATO. SACLANTCEN, 1993/10)Duda et al. [J. Acoust. Soc. Am. 92(2), 939-955, 1992] have measured wavefront arrival times over a -
Efficient global matrix approach to the computation of synthetic seismograms
(NATO. SACLANTCEN, 1986/05)A numerically efficient global matrix approach to the solution of the wave equation in horizontally stratified environments is presented. The field in each layer is expressed as a superposition of the field produced by the ... -
EM phenomena in the ELF range: EM fields of submerged dipoles and finite antennas
(NATO. SACLANTCEN, 1965/06)The report is the first of a series of three that discusses various EM phenomena in the ELF range. The expressions for the various components of the EM field from submerged dipoles are presented. Although similar expressions ... -
EM phenomena in the ELF range: natural background noise and instrumentation for its measurement
(NATO. SACLANTCEN, 1965/06)The report is the second of a series of three that discusses various EM phenomena in the ELF range. A general outline of the natural background noise in the frequency range between 1 and 50 cps is given and the measurement ...