Browsing CMRE Publications by Title
Now showing items 636-655 of 882
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Real-time expanded-band beamforming using a complex heterodyner and fast array processor
(NATO. SACLANTCEN, 1979/12)At the Defense Research Establishment Atlantic Dartmouth, Nova Scotia, Canada a data aquisition sytem been engineered to monitor and beamform data from element line arrays. This system has been designed to with either towed ... -
Real-time mosaicing of large scale areas with forward looking sonar
(CMRE, 2019/06)Mosaicing of large scale areas is an important application in the field of underwater computer vision. Although most of the works use optical cameras for that purpose, Forward Looking Sonars, also called acoustic cameras, ... -
Real-time processing of acoustic and oceanographic data at sea
(NATO. SACLANTCEN, 1972/05) -
Real-time underwater positioning and navigation of an AUV in deep waters
(CMRE, 2019/05)Due to the absence of GPS, navigation of autonomous vehicles underwater requires the integration of various measurements to provide the best location estimate. Usually in littoral waters, adequate navigational accuracy may ... -
Real-time, general-purpose, high-speed signal processing systems for underwater research: proceedings of a working-level conference held at SACLANTCEN on 18-21 September 1979 - part 1 : sessions 1 to 3
(NATO. SACLANTCEN, 1979/12)During the last few years, advances in the computer field have reached a level where it is possible to implement fast signal-processing systems through the use of standard computer equipment operating in association with ... -
Realistic extended target model for track before detect in maritime surveillance
(CMRE, 2019/06)Traditional target tracking algorithms are generally fed a set of thresholded detections under the hypothesis that no more than one detection is generated by each single target. Improvements in modern radar systems have ... -
Realistic ship model for extended target tracking algorithms
(CMRE, 2019/06)Recent developments in high resolution sensors have encouraged the use of Extended Target Tracking (ETT) algorithms specifically designed to deal with targets that generate more than one detection per frame. At the same ... -
Receiving and transmitting acoustic systems for AUV/gliders
(NURC, 2009/12)NURC in the past years have focused its research on the use of AUV and more recently on gliders and is now developing littoral autonomous sensing networks based onthose sensors to perform missions such as mine warfare, ... -
Recent technological advances in underwater autonomy
(2019/05)Underwater Unmanned systems (or more precisely systems of systems) will definitely play an important role in future maritime surveillance and environmental data collection. For many years, the NATO Centre for Maritime ... -
Redesigning the SLOCUM glider for torpedo tube launching
(NURC, 2012/04)Launching gliders from a submarine torpedo tube is of special interest for military operations. This is not currently possible because the wing span needed to achieve a good gliding performance is twice the standard diameter ... -
Reduction of low frequency active sonar clutter through image processing
(NATO. SACLANTCEN, 1997/12)Large numbers of false clutter detections arise in the use of low frequency active sonar for the detection of low Doppler submarine targets in shallow water. Traditional detection algorithms operate individually on each ... -
Reflection of sound from a layered ocean bottom
(NATO. SACLANTCEN, 1975/10) -
Refraction of sound in the sea floor
(NATO. SACLANTCEN, 1975/10)A major mode of propagation of acoustic energy at low frequencies is a shallow refracted path through unconsolidated sediments of the sea floor. Successful modelling of the bottom-refracted mode of propagation requires ... -
Regional reflection seismic exploration of the Strait of Sicily
(NATO. SACLANTCEN, 1972/09)A regional seismic reflection survey was performed by OGS in 1970 on the Sicily Channel, using multichannel digital techniques and flexotir source. Reflections up to about 5 s (two-way time) have been obtained. The analysis ... -
Relating in situ shear wave velocity to void ratio and grain size for unconsolidated marine sediments
(NATO. SACLANTCEN, 1997)Recent advances in field hardware have meant that it has become possible to measurein situ shear wave velocity in the upper few decimetres of sea floor sediment in a routine manner. It is known that shear wave velocity can ... -
Relative contribution of surface roughness and bottom attenuation to propagation loss in shallow water
(NATO. SACLANTCEN, 1975/10)A simulation study has been performed to investigate the relative importance of the contributions of surface roughness and bottom attenuation to propagation loss under differing environmental conditionso The NRL normal ... -
A relocatable EnKF ocean data assimilation tool for heterogeneous observational networks
(CMRE, 2019/06)This study investigates the performance of a multivariate Ensemble Kalman Filter coupled with a relocatable limited-area configuration of the Regional Ocean Modeling System to predict ocean states by assimilating a ... -
Remote sensing of topographically-induced upwelling in the southern coastal region of Sicily
(NATO. SACLANTCEN, 1998/09)Upwelling signatures caused by variations in bottom topography along the southeastern Sicilian coast are identified, using spaceborne remote sensing Advanced Very High Resolution Radiometer (AVHRR) imagery, ERS-1 and ... -
Resonance analysis of the acoustic response of a water-filled cylindrical shell
(NATO. SACLANTCEN, 1998/09)The resonance analysis approach developed for characterizing free-field air-filled cylindrical shells in terms of geometrical and mechanical pararneters is extended to fluid-filled shells either in the freefield or proud ...