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Noncontact Wideband Sonar for Human Activity Detection and Classification
IEEE Sensors Journal, 2014This paper suggests using a wideband sonar system to detect and classify human activity in indoor environment. The high bandwidth enables precise tracking of body parts, and its enhanced correlation properties can be used to dis- tinguish between human and nonhuman objects.
Gaddi Blumrosen +2 more
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Environmentally invariant features for classification of active sonar signals.
The Journal of the Acoustical Society of America, 2009Dispersion and damping (frequency-dependent spreading and attenuation) can be significant in shallow water sound propagation. These propagation-induced effects can be detrimental to classification of active sonar returns because the observed backscatter depends not only on the target, but also on the propagation environment and how far the wave has ...
Patrick Loughlin, Greg Okopal
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Applying neural networks to automatic active sonar classification
[1990] Proceedings. 10th International Conference on Pattern Recognition, 2002The usefulness of applying neural network technology to active sonar classifier development is discussed. The authors offer qualitative results to help those interested in assessing this technology to reach a deeper understanding of its value. At a minimum, the nature of the observations strongly suggest that the best way to evaluate neural network ...
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Examining the robustness of automated aural classification of active sonar echoes
The Journal of the Acoustical Society of America, 2014Active sonar systems are used to detect underwater man-made objects of interest (targets) that are too quiet to be reliably detected with passive sonar. Performance of active sonar can be degraded by false alarms caused by echoes returned from geological seabed structures (clutter) in shallow regions.
Stefan M, Murphy, Paul C, Hines
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Optimum object classification with active sonar: new theoretical results
IEEE International Conference on Systems Engineering, 2002The active sonar classification problem is considered. To perform active classification, a known waveform is transmitted into a medium and directed towards a region called the test volume. An array of sensors is used to pick up the backscattered signal energy reflected from the cells of the test volume.
J.G. Kelly +3 more
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Active sonar classification using perceptual signal features from musical acoustics
The Journal of the Acoustical Society of America, 2006Because of the relatively low frequencies at which they operate, navy active sonars are often plagued by false-alarm returns resulting from geological structures. In the lexicon of sonar operators these false returns are referred to as geoclutter or simply clutter.
Victor W. Young +2 more
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Human Activity Classification in Underwater using Sonar and Deep Learning
Proceedings of the International Conference on Underwater Networks & Systems, 2019In this paper, we study the classification of human activity on the surface of a body of water using sonar. In particular, we investigate the classification of three different swimming styles; freestyle, butterfly, and backstroke. Experiments are conducted in a swimming pool to capture acoustic micro-Doppler signatures produced by the different ...
Hovannes Kulhandjian +3 more
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Waveguide invariant minimum variance scatterer depth classification for active sonar.
The Journal of the Acoustical Society of America, 2010Active sonar systems are plagued by false alarms due to confusion between returns from water-column targets and backscatter from the bottom. Both feature-based and physics-based classifiers are notoriously susceptible to mismatch of the environment used for training and/or modeling active sonar returns.
Ryan Goldhahn +2 more
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Environmentally tolerant waveguide-invariant target depth classification for active sonar.
The Journal of the Acoustical Society of America, 2010Shallow-water environments produce active sonar returns with many target-like returns from bottom clutter. Scatterer depth classification methods which can discriminate bottom clutter from water column targets are thus critical for controlling false alarms. In recent work, the waveguide invariant (WI) property of shallow-water channels has been used to
Ryan Goldhahn +2 more
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Application of musical timbre discrimination features to active sonar classification
The Journal of the Acoustical Society of America, 2005In musical acoustics significant effort has been devoted to uncovering the physical basis of timbre perception. Most investigations into timbre rely on multidimensional scaling (MDS), in which different musical sounds are arranged as points in multidimensional space.
Victor W. Young +2 more
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