Browsing CMRE Publications by Title
Now showing items 248-267 of 882
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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 ... -
Deep-sea circulation in the Alboran sea
(NATO. SACLANTCEN, 1985/04)Alboran Sea circulation between 220 and 1100 m depth is studied. Interaction between three types of water masses in this area causes a complicated flow pattern. Atlantic water flowing as a jet through the Strait of Gibraltar ... -
Delay-Doppler resolution performance of large time-bandwidth product linear FM signals in a multi- path ocean environment
(NATO. SACLANTCEN, 1989/04)Active sonar systems that transmit large time-bandwidth (TW)-product linear frequency modulated (LFM) waveforms and receive echoes from targets of unknow~r~an ge and speed can suffer considerable correlation losses that ... -
Demystifying deep convolutional neural networks for sonar image classification
(CMRE, 2019/06)Deep convolutional neural networks (CNNs) are developed to perform underwater target classification in synthetic aperture sonar (SAS) imagery. The deep networks are trained using a huge database of sonar data collected at ... -
Deployable underwater surveillance systems(DUSS): localization and fusion of multistatic contacts: evaluation of feasibility using experimental data
(NATO. SACLANTCEN, 1998/12)Active sonar deployable underwater surveillance systems (DUSS) are based on a distributed network -
Deployable underwater surveillance systems: analysis of experimental results: part III
(NATO. SACLANTCEN, 1999/04)Deployable Underwater Surveillance Systems (DUSS) are a new active sonar concept based on a distributed network of small multistatic transmitter / receiver nodes. This study analyzes data acquired during the period 29 June ...