Browsing CMRE Publications by Title
Now showing items 90-109 of 882
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Acoustic scattering from rough surfaces
(NATO. SACLANTCEN, 1975/10)A review of scattering from the ocean bottom and ocean ice cover is given. Areas of deficiency are cited. -
Acoustic scintillations of acoustic waves
(NATO. SACLANTCEN, 1975/10) -
Acoustic signal dispersion and distortion by shallow undersea transmission channels
(NATO. SACLANTCEN, 1997)The undersea littoral is an adverse medium for acoustic signal transmission to horizontal ranges of many water depths. Reflections and scattering in the bounded, nonhomogeneous channel disperse the arrivaj of received ... -
Acoustic source characteristics of merchant ships
(NATO. SACLANTCEN, 1982/06)Merchant ships are sources of broadband acoustic noise which can interfere with and confuse ocean surveillance. The purpose of this discussion is to review: the status of research on and measurements of merchant ship ... -
Acoustic source-level measurements for a variety of merchant ships
(NATO. SACLANTCEN, 1988/07)This report describes a set of 50 source spectra obtained from merchant ships of opportunity near Genova, Italy. These spectra were obtained from radiated-noise spectra measured on a towed array and a transmission-loss ... -
Acoustical characteristics of the sea floor: experimental techniques and some examples from the Mediterranean Sea
(NATO. SACLANTCEN, 1974/11)The acoustical properties of the sea floor are primarily determined by the physical properties of the sediments, layering in the sediments, and the roughness of the bottom and sub-bottom. Over the last decade many cores ... -
Acoustical probing for microbubbles at sea
(NATO. SACLANTCEN, 1975/10)Free gas bubbles have been indicted for many physical processes at sea including: scavenging detritus and chemicals from the ocean volume; generating droplets whose salts affect thunderstorm activity over the sea; providing ... -
Active contours for synthetic aperture sonar snippet registration
(CMRE, 2019/06)In mine-hunting operations, there is currently a strong focus on using autonomous systems in order to remove personnel and ships from the minefield. These systems must perform their missions effectively, and the collected ... -
Active detection enhancement in coastal areas
(NURC, 2006/08)The processing chain used for active detection analysis in association with measures of performance that allow real time performance monitoring is presented. Real life examples demonstrating environmental volatility ... -
Active signal detection in shallow water using the Page test
(NATO. SACLANTCEN, 1996/11)The use of active sonar in shallow water results in received echoes that may be considerably spread in time compared to the transmitted wave form. The duration and structure of the spreading and the time of occurrence of ... -
Adaptive autonomous underwater vehicles for littoral surveillance: the GLINT10 field trial results
(NURC, 2012/05)Autonomous underwater vehicles (AUVs) have gained more interest in recent years for military as well as civilian applications. One potential application of AUVs is for the purpose of undersea surveillance. As research into ... -
An adaptive cross-layer routing protocol for underwater acoustic networks
(2019/05)This short paper presents an adaptive cross-layer routing protocol for Underwater Acoustic Networks (UANs). The proposed solution, termed NADIR for Network Aware aDaptIve Routing, is fully distributed and self-adaptive. ... -
Adaptive filter of seabed clutter onboard the AUVs of an active multistatic sonar network
(CMRE, 2019/05)This work aims at reducing the false alarm rate of a multistatic active sonar working in coastal, shallow waters. The sonar system is implemented through a heterogeneous manned-unmanned network including autonomous underwater ... -
Adaptive filtering of imprecisely time-stamped measurements with application to AIS networks
(CMRE, 2019/06)Driven by real-world issues in maritime surveillance, we consider the problem of estimating the target state from a sequence of observations that can be imprecisely time-stamped. That is, the time between two consecutive ... -
Adaptive normalization of active sonar data
(NURC, 2006/08)In active sonar detection the background interference is reduced through normalization prior to applying a detection threshold. From the two mainstream normalization algorithms, i.e. the sliding window and the split window, ... -
Adaptive sub-band processing in active detection and tracking
(NURC, 2007/11)Broadband active systems have the potential to increase detection performance in reverberation-limited areas through increased signal bandwidth, i.e. small resolution cell. However, large bandwidth could over-resolve the ... -
Adaptive underwater sonar surveys in the presence of strong currents
(CMRE, 2017/11)We consider the task of conducting underwater surveys with a sonar-equipped autonomous underwater vehicle (AUV) in environments with strong currents. More specifically, this topic is addressed in the context of mine ... -
Advanced digital processor research at DREA
(NATO. SACLANTCEN, 1979/12)This informal presentation deals with an array processor built by ESE Ltd of Toronto under contract to the Defense Research Establishment Atlantic, Dartmouth, Nova Scotia, Canada. The processor and software was delivered ... -
Advances in cots side scan sonar for MCM applications
(NATO. SACLANTCEN, 1997)The Persian Gulf War has elevated the awareness to the problems of shallow water mine detection. Today's high technology shallow water anti-invasion mines, such as the Italian made "MANTA" and the Swedish manufactured ...