Browsing CMRE Publications by Subject "Target detection"
Now showing items 21-40 of 40
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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 ... -
Modelling scattering from partially buried cylinders = Acoustic scattering from cylindrical objects embedded between two half-spaces/The computation of the scattered pressure field from a cylinder embedded between two half-spaces = The computation of the scattered pressure field from a cylinder embedded between two half-spaces with different densities
(NATO. SACLANTCEN, 1996/12)1. A boundary integral equation method is presented for the computation of the acoustic field scattered from a cylindrical object which is totally within the water column, totally buried in sediment, or partially buried. ... -
The Mondrian detection algorithm for sonar imagery
(CMRE, 2019/06)A new algorithm called the Mondrian detector has been developed for object detection in high-frequency synthetic aperture sonar (SAS) imagery. If a second (low) frequency-band image is available, the algorithm can seamlessly ... -
Multi-look processing of high-resolution SAS data for improved target detection performance
(CMRE, 2019/06)The rich content of synthetic aperture sonar (SAS) data is typically used to generate imagery with resolution as high as theoretically possible. But when the ultimate purpose of the imagery is for detecting objects with ... -
On adaptive underwater object detection
(NURC, 2012/04)A new algorithm for the detection of underwater objects in sonar imagery is proposed. One particularly novel component of the algorithm also detects the presence of, and estimates the orientation of, sand ripples. The ... -
On the relationship between SAS image resolution and target-detection performance
(CMRE, 2019/06)The relationship between synthetic aperture sonar (SAS) image resolution and target-detection performance is quantified. It is first demonstrated how a lower-resolution SAS system can be simulated in a principled manner ... -
Optimal detection and tracking of acoustical noise sources in a time-varying environment
(NATO. SACLANTCEN, 1982/06)A dynamical detector estimator is derived for nonlinear nongaussian signal processes based on Bucy's representation theorem which is the fundamental result in stochastic filtering. A quantized version of two-dimensional ... -
Passive acoustic detection of marine mammals
(NATO. SACLANTCEN, 2000/04)A passive acoustic analysis of data recorded during the SACLANTCEN -
Range estimation of cetaceans with compact volumetric arrays
(CMRE, 2014/01)Passive acoustic monitoring is the method of choice to detect whales and dolphins that are acoustically active and to monitor their underwater behaviour. The NATO Science and Technology Organization Centre for Maritime ... -
Real-and synthetic-array signal processing of buried targets
(NATO. SACLANTCEN, 2002/01)Results from two field experiments aimed at investigating the detection and classification of buried targets are presented. In both experiments a 2-16 kHz parametric source was used. In the first experiment the source was ... -
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 ... -
Single ping clutter reduction: segmentation using Markov random fields
(NATO. SACLANTCEN, 1999/03)The use of low frequency active sonar in shallow water leads to large numbers of clutter detections. This high false alarm rate can overload automatic tracking and classification algorithms. Traditional detection algorithms ... -
Statistical normalization of non-Rayleigh reverberation
(NATO. SACLANTCEN, 2000/02)Low-frequency active sonar systems operating in shallow water are primarily limited by reverberation. -
SUPREMO: a multistatic sonar performance model
(NATO. SACLANTCEN, 2002/11)Multistatic sonars introduce new problems to the modeller such as mutual interference from multiple sources and variable target aspect in a background of range-dependent bistatic reverberation. A multistatic sonar performance ... -
Target detection and location with ambient noise
(NURC, 2008/09)By placing a vertical array in an ambient noise field and forming an upward and a downward beam one obtains two time series which can be cross correlated to reveal a subbottom profile of the seabed [Siderius et al., J. ... -
Target detection using a three-layered neural network trained by supervised back-propagation
(NATO. SACLANTCEN, 1990/05)In any sonar system a detection process has to be performed at -
Target motion effects on passive sonar: an appraisal of basic factors
(NATO. SACLANTCEN, 1986/12)Detection and tracking by passive sonar involve the observation of the target-radiated noise in bearing-cells and time-cells that have their dimensions predetermined by a combination of physical limitations, e.g. the size ... -
The intrinsic variability of detection range and its implications
(NURC, 2009/12)The range of first detection of an approaching target is among the most important parameters defining sensors and defensive surveillance systems. A demonstration of capability typically consists of staged approaches of a ... -
The propagation and reception of transient electromagnetic signals in the presence of a conducting half-space
(NATO. SACLANTCEN, 1961/05)In this paper a theoretical treatment is given of the short-distance propagation and reception of a step-function in the presence of a conducting half-space. The step-function is generated by a horizontal electric dipole ... -
Underwater source localization using a hydrophone-equipped glider
(CMRE, 2014/01)Buoyancy-driven underwater gliders are autonomous underwater vehicles that were originally developed to collect oceanographic data. CMRE is studying the use of this technology for the characterization of denied areas, ...