Browsing Reprints by Title
Now showing items 7-26 of 548
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A conversational processing system of acoustic data for use on land and at sea: SPADA
(NATO. SACLANTCEN, 1972/05) -
A data-driven control strategy in synergy with continuous active sonar for littoral underwater surveillance
(CMRE, 2017/11)In this work, we describe a data-driven Mission Management Layer (MML) running on-board AUVs which manages the phases of a littoral surveillance mission and exploits the characteristics of Continuous Active Sonar (CAS) ... -
A deep stepped thermohaline structure deep in the Mediterranean
(NATO. SACLANTCEN, 1972/09)A deep stepped thermohaline structure has been observed in the Tyrrhenian Sea below the Levant ine water salinity maximum. The layers are remarkably homogeneous starting with a thickness of 10 m - 20 m at 600 m and thereafter ... -
A direct digital acquisition system
(NATO. SACLANTCEN, 1972/05) -
A distributed ID assignment and topology discovery protocol for underwater acoustic networks
(CMRE, 2017/11)This paper presents a new protocol to self assign node IDs in an Underwater Acoustic Network (UAN). The proposed solution, termed DIVE for Distributed Id assignment and topology discoVEry, is fully distributed and ... -
A fast display processor for sonar echoes
(NATO. SACLANTCEN, 1979/12)This paper presents a display processor for a CRT, which shows a horizontal projection of underwater targets. Sonar echoes are drawn as short lines across a 50 beam, in random scan and with 50 Hz refresh. The high speed ... -
A fast field model for three-dimensional wave propagation in stratified environments based on the global matrix method
(NATO. SACLANTCEN, 1986/03)A three-dimensional fast field program (FFP) model based on the global matrix method will be presented. Compared to traditional propagator matrix methods, the global matrix method allows for a more efficient, and, furthermore, ... -
A general purpose software system for applications in different fields of physics
(NATO. SACLANTCEN, 1979/12)The paper presents the principle of a software system (FTSS) developed by the Danish Defence Research Establishment (DDRE) for applications in different fields of physics. Software is made up by independent modules exchanging ... -
A high frequency approach for seabed vegetation characterization
(NATO. SACLANTCEN, 1997)This paper focuses on the characterization of seabed vegetation, an interesting problem in a lot of Mediterranean sea coastal sites since water quality and pollution degree can be efficaciously solved by investigating the ... -
A method of estimating the influence of ship's noise on ambient noise measurements
(NATO. SACLANTCEN, 1982/06)Ambient noise measurements are often adversely affected by noise from passing ships. Here, a method is presented which allows the estimation of this influence. The method is especially suitable for shallow water applications. ... -
A micro-programmable correlator for real-time radar processing
(NATO. SACLANTCEN, 1979/12)This paper presents a novel design of a multibit, digital correlator for incoherent scatter radar observations. By utilizing bit-slice microprocessor elements and internal control by microcode instructions, a high-speed ... -
A modular approach to signal processing
(NATO. SACLANTCEN, 1979/12)This paper outlines work in progress on modular systems for beamforming and signal processing. The modules described were developed using commercially available digital L.S.I circuits and the emphasis during development ... -
A modular signal processing software development system
(NATO. SACLANTCEN, 1979/12)A software development system is being built by the U.S. Naval Research Laboratory (NRL) to aid production of modular signal processing software for U. S. Navy airborne ASW platforms using the Navy's Advanced Signal Processor ... -
A new ambient noise imaging system for ANI, passive and bistatic active acoustic imaging in shallow water
(NATO. SACLANTCEN, 1997)Shallow water active and passive sonars can be usefully complimented by broadband Ambient Noise Imaging (ANI) systems. The first AN1 system was largely analogue, produced good images at 38 m range, but was bulky and permitted ... -
A noise directionality model including variable bathymetry
(NATO. SACLANTCEN, 1997)In this paper we investigate the noise directionality due to distributed surface sources m several envtronments with a uniformly sloping sea bed. Of particular interest are frequency dependence and the question of the ... -
A novel approach for a bistatic scattering calculation suitable for sonar performance model
(CMRE, 2014/01)One of the classical approaches to the calculation of the sound pressure scattered from a rough surface is to sum the contributions to the field from a set of small tiles that approximate the surface. If the tiles are ... -
A novel method to enlarge the scanning region of a focused beamformer
(NATO. SACLANTCEN, 1997)Often focused beamforming systems use the Fresnel approximation to compute the required delays. Unfortunately, such an approximation has a validity region that is very narrow around the broadside direction. To investrgate ... -
A parametric examination of some properties of the low-frequency ambient noise field
(NATO. SACLANTCEN, 1982/06)Models for ship-generated ambient noise vary considerably in the detail required of their input data on sources and the environment. This paper describes a model that predicts ambient-noise levels and cumulative distribution ... -
A PC/Linux software toolkit for coastal swath mapping
(NATO. SACLANTCEN, 1997)Assembly of a PC/Linux based data acquisirion and processing software toolkit for coastal (shallow water) multibeam and sidescan swath mapping sonar systems has been undertaken by the URI Ocean Mapping Development center ... -
A real time system for towed array calibration and performance analysis, or how to get 50 dB sidelobes from a towed array
(NATO. SACLANTCEN, 1982/06)Sidelobe suppression levels of 30 dB for a towed array are generally considered excellent; values above that are considered exceptional or unachievable. However, 40 t o 50 dB suppression levels have been achieved and ...