Browsing Technical Reports by Title
Now showing items 123-142 of 322
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Fast Fourier transformation algorithms: experiments with microcomputers
(NATO. SACLANTCEN, 1986/07)We describe experiments intended to exploit the potential of modern -
Finite difference modelling of scattering by objects in the seabed
(NATO. SACLANTCEN, 1996/07)In this report we describe the theory and some implementation issues of a finite difference code used at SACLANT Centre. In particular, we consider the modelling of attenuation and the excitation of a remote incident field ... -
Formulae for bistatic signal and reverberation
(NATO. SACLANTCEN, 2002/12)This report demonstrates that it is possible to obtain closed-form solutions for signal and reverberation in a wide variety of bistatic scenarios including ducts and bottom bathymetry. These formulae adapt earlier monostatic ... -
Frequency deviation indicator
(NATO. SACLANTCEN, 1963/11)A new type of discriminator was developed to measure the frequency variation of electrical signals; it has the special feature to indicate without any delay the difference between the signal frequency and some fixed reference ... -
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 ... -
Geo-acoustic inversion of the PROSIM'97 experimental data using simplex simulated annealing
(NATO. SACLANTCEN, 2000/01)In the spring of 1997 SACLANTCEN performed an experiment near the Elba island in the Mediterranean Sea. The PROSIM'97 experiment was designed for the validation of a broadband acoustic propagation model. During the period ... -
Geoacoustic models for selected shallow water areas
(NATO. SACLANTCEN, 1996/07)This report summarizes recent work on characterization of shallow water -
Geoenvironmental characterization of selected shallow-water sites on the western European continental shelf (SWAP)
(NATO. SACLANTCEN, 1995/04)Geoenvironrnental analyses for four experiment sites on the continental -
GLider Acoustics Sensing of Sediments (GLASS): experiments and data analysis
(CMRE, 2013/12)Seabed characteristics (geoacoustic properties and scattering strength) are critical parameters for sonar performance predictions. However, this bottom information is considered very difficult and expensive to achieve in ... -
High resolution geoacoustic inversion in shallow water: a joint time and frequency domain technique
(NATO. SACLANTCEN, 1998/12)High resolution geoacoustic data are quired for accurate predictions of -
High-resolution analysis of non-stationary data ensembles
(NATO. SACLANTCEN, 1980/10)Estimation of an unknown parameter of a random data ensemble is usually done by maximizing a certain power estimator by varying the unknown parameter. This method is convenient where the data are a nonlinear function of ... -
High-resolution beamforming techniques performance analysis
(NATO. SACLANTCEN, 1986/11)Seven different beamforming techniques (including both conventional and high-resolution types) have been analyzed and compared in order to develop a quantitative relationship between resolution performance on the one hand ... -
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 ... -
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 ... -
Hydrographic measurements in the southern Iceland and Norwegian Seas during June and August, 1989
(NATO. SACLANTCEN, 1993/12)This memorandum documents an extensive collection of CTD data made during two cruises in the region between Greenland and Norway -
Hydrography of the Iceland-Faeroe Ridge during March 1992: environmental data during NORDIC 92
(NATO. SACLANTCEN, 1992/12)This memorandum documents an extensive collection of CTD and XBT data made on the Iceland-Faeroe Ridge in March, 1992 by the SACLANTCEN vessel Alliance and the FWG vessel Planet as part of a larger operation called NORDIC ... -
Icelandic current experiment GIN Sea Cruise 88 data report: Hydrography and circulation: volume 1
(NATO. SACLANTCEN, 1992/09)The hydrographic and circulation data from the GIN '88 cruise on board the R/V Alliance are summarised in this data report. This cruise constituted the first component of the Icelandic Current Experiment, an observational ...