Browsing by Title
Now showing items 243-262 of 882
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Continuous active sonars for littoral undersea surveillance
(CMRE, 2019/05)Recent advances in transducer and computing technology have pushed the concept of continuous active sonar (CAS) or high duty cycle sonar as an area of interest for application to antisubmarine warfare. Unlike conventional ... -
Continuous recording of active sonar data
(NATO. SACLANTCEN, 1972/05) -
Converted measurements Bayesian extended target tracking applied to X-band marine radar data
(CMRE, 2019/06)X-band marine radar systems are flexible and low-cost tools for monitoring multiple targets in a surveillance area. They can provide high resolution measurements both in space and time. Such features offer the opportunity ... -
Converted measurements random matrix approach to extended target tracking using X-band marine radar data
(CMRE, 2019/06)Conventional tracking algorithms rely upon the hypothesis of one detection per target for each frame. However, very fine spatial resolution radars represent widespread systems that provide data for which this hypothesis ... -
Cooperation and networking in an underwater network composed by heterogeneous assets
(CMRE, 2019/06)Underwater communication and robot technologies have grown rapidly in the last decade. Systems made of underwater unmanned vehicles have moved from single vehicle deployments to systems comprising teams of assets. As of ... -
Cooperative robotic networks for underwater surveillance: an overview
(CMRE, 2019/06)Underwater surveillance has traditionally been carried out by means of surface and undersea manned vessels equipped with advanced sensor systems. This approach is often costly and manpower intensive. Marine robotics is an ... -
Correlation of backscatter with bottom topography
(NATO. SACLANTCEN, 1993/08)Practical data from low frequency sonar operations in shallow water has been analysed to demonstrate that a high degree of correlation exists between the received signal due to bottom hackscattering and the hottom gradient ... -
Counter piracy surveillance requirements for early detection, military rescue, or evasion
(NURC, 2012/06)Best practice for protection against pirates includes coordination with the military forces operating in the area, constant watch against the approach of pirates, and measures to prevent or delay their boarding. The time ... -
Coupled-mode modelling of acoustic scattering from three-dimensional, axisymmetric objects
(NATO. SACLANTCEN, 1997/01)In this memorandum a coupled-mode method for computing the wavefield scattered by three-dimensional, axisymmetric objects is presented. The method provides a unified approach to solving three-dimensional scattering problems ... -
Critical angle and seabed scattering issues for active-sonar performance predictions in shallow water
(NATO. SACLANTCEN, 1997)Active sonar performance predictions (0.75 to 3 kHz) are examined in summer shallow-water environments to quantify the impact of variable seabed and watermass properties on detection. Scattering is computed with an ... -
Current regulatory issues in the usage of autonomous underwater vehicles
(CMRE, 2019/05)Autonomous Surface Vehicles (ASVs) are becoming increasingly popular for a large number of applications from oceanography to border protection and shipping. In particular, the advent of long-term ASVs allows for months-long ... -
Data communication and data fusion architecture for RAPID RESPONSE 96-98
(NATO. SACLANTCEN, 1999/06)Executive Summary: The concept of Rapid Environmental Assessment (REA) has emerged in recent years as one of the most interesting research topics in Military Oceanography (MILOC): REA in a military environment is defined ... -
Data driven vessel trajectory forecasting using stochastic generative models
(2019/05)In this work, we propose a data driven trajectory forecasting algorithm that utilizes both recorded historical and streaming trajectory observations. The algorithm performs Bayesian inference on a directed graph the walks ... -
Data-driven detection and context-based classification of maritime anomalies
(CMRE, 2019/06)Discovering anomalies at sea is one of the critical tasks of Maritime Situational Awareness (MSA) activities and an important enabler for maritime security operations. This paper proposes a data-driven approach to anomaly ... -
Decay of large underwater bubble oscillations
(NATO. SACLANTCEN, 1999/02)Pressure - time series from breathing mode oscillation of large (centimeter scale or larger) underwater bubbles reveal much higher decay rates than can be explained using viscous, thermal, or radiative mechanisms which ... -
Decision tree-based adaptive modulation for underwater acoustic communications
(CMRE, 2017/11)Underwater acoustic channels are characterised by non-stationary fading statistics and consequently, a modulation scheme optimally designed for a specific fading model will underperform when the channel statistics ... -
Deconvolution by homomorphic and Wiener filtering
(NATO. SACLANTCEN, 1988/09)This study is concerned with deconvolution methods applied to underwater propagation in shallow -
Deduction fo synthetic temperature profiles from SST observations in the Iceland-Faeroe frontal region
(NATO. SACLANTCEN, 1996/01)Subsurface temperature and sound speed profiles are generated from satellite SST observations and -
Deep water mass circulation in the Alboran Basin: Measurements - August to November'83: ALBORAN III
(NATO. SACLANTCEN, 1988/02)The circulation of the deep water mass in the western Alboran Sea is studied. Interaction between the -
Deep water mass circulation in the Alboran basin: measurements - January to April '82 ALBORAN II
(NATO. SACLANTCEN, 1987/09)Alboran Sea circulation between 220 m and 1100 m depth is studied. Interaction between three water types, Atlantic water, Levantine water, and western Mediterranean Deep water cause a complicated flow pattern. Atlantic ...