Browsing Reprints by Title
Now showing items 276-295 of 548
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Localization of small surface vessels through acoustic data fusion of two tetrahedral arrays of hydrophones
(CMRE, 2014/01)Detection and tracking of vessels is important in confined areas such as marine parks or harbors. Nowadays, the presence of ships can be accurately monitored either by radar or via AIS system, while small vessels, which ... -
Long-term vessel kinematics prediction exploiting mean-reverting processes
(CMRE, 2019/06)Long-term target state estimation of non-manoeuvring targets, such as vessels under way in open sea, is crucial for maritime security. The dynamics of non-manoeuvring targets is traditionally modelled with a white noise ... -
Low frequency active sonar (LFA) bottom loss requirements
(NATO. SACLANTCEN, 1993/08)A bottom interaction simulator was developed to investigate LFA bottom bounce losses, i.e., the mismatch losses, which occur in matched filter processing of bottom and target reflected signals due to the time spreading ... -
Low frequency active sonar noise rejection in a multistatic sonar system
(NATO. SACLANTCEN, 1993/08)The use of low frequency active sonar for ASW has repercussions on automated detection performance. Input data contain not only target returns, but also noise formed by returns from the environment The detector may report ... -
Low frequency resonance backscatter from near-surface bubble clouds
(NATO. SACLANTCEN, 1993/08)When active sonar systems are used to insonate the sea surface, anomalous scattering is observed in the form of enhanced backscatter, and more importantly, in the form of discrete, bright echoes. The most plausible explanation ... -
Low-frequency acoustic measurements in a shallow-water area with a rough sea surface
(NATO. SACLANTCEN, 1975/10)Surface wave spectra have been measured in the North Sea simultaneously with acoustic investigations using explosive and CW sources. The goal of these experiments was to determine the influence of surface waves to low-frequency ... -
Low-frequency ambient noise in the deep sound channel: the missing component
(NATO. SACLANTCEN, 1981/07)There is an important component of the undersea ambient noise which has generally been overlooked or ignored. It is the noise which arrives at a sensor, located in a deep sound channel, by way of ducted sound propagation. ... -
Low-frequency seismic and hydroacustic noise measurements in a fjord
(NATO. SACLANTCEN, 1982/06)Low frequency ambient noise signals from an ocean bottom seismometer (oBS) put on the sea floor of a Norwegian fjord have been studied. The instrument contains 3 seismometers and one hydrophone, and signals from all 4 ... -
Magnetic, gravity and depth surveys in the Mediterranean and Red Sea
(NATO. SACLANTCEN, 1965/04)This report is a copy of a paper published in Nature, Vol. 204, 4965, 1964: 1245-1248 by T.D. Allan of this Centre, H. Charnock of this Centre at the time of the surveys but now of the National Institute of Oceanography, ... -
MAP 300/AP 120B comparison
(NATO. SACLANTCEN, 1979/12) -
Maritime anomaly detection based on mean-reverting stochastic processes applied to a real-world scenario
(CMRE, 2019/05)A novel anomaly detection procedure based on the Ornstein-Uhlenbeck (OU) mean-reverting stochastic process is presented. The considered anomaly is a vessel that deviates from a planned route, changing its nominal velocity ... -
Maritime defense and security challenges
(CMRE, 2019/06) -
Maritime situational awareness use cases enabled by space-borne sensors
(CMRE, 2019/06)This paper discusses a technique for predicting a vessel?s position over a long time horizon with much lower uncertainty than current methods. Lowering the uncertainty of long-range prediction is a key challenge in maritime ... -
Maritime surveillance using multiple high-frequency surface-wave radars
(CMRE, 2014/05)In the last decades, great interest has been directed toward low-power high-frequency (HF) surface-wave radars as long-range early warning tools in maritime-situational-awareness applications. These sensors, developed for ... -
Maritime surveillance with multiple over-the-horizon HFSW radars: an overview of recent experimentation
(CMRE, 2019/06)This paper briefly explores the high-frequency surface-wave (HFSW) radar technology in general, and Wellen radar (WERA) in more detail. Then it describes the multitarget tracking data fusion (MTTDF) network architecture ... -
A market-based task allocation framework for autonomous underwater surveillance networks
(CMRE, 2019/06)Realisation of underwater robotic surveillance networks raises several challenges for marine robotics. The underwater scenario is typically characterised by intermittent and unreliable communication. This makes it challenging ... -
Martinus - multiprocessor for high capacity real-time processing
(NATO. SACLANTCEN, 1979/12)Development of circuit technology in recent years now makes it feasible to build powerful processing machines at quite considerable savings - in comparison to those which have been considered feasible earlier. These savings ... -
MASCOT - a modular software construction system
(NATO. SACLANTCEN, 1979/12) -
Measurement and interpretation of angular spreading from multiple boundary interactions in a shallow water channel
(NATO. SACLANTCEN, 1997)The problem of angular spreading of sound that has undergone multiple boundary scattering (both sea surface and sea bed) in a shallow water channel is discussed. Measurements made of the horizontal spatial coherence along ... -
Measurement of the bubble population in coastal waters using combination frequencies of MHz order
(NATO. SACLANTCEN, 1997)This paper describes the use of a combinatron frequency technique to measure the size distribution of oceanic bubbles. Written between two sea trials, the paper describes how the apparatus cart be adapted to design tests ...