Results 241 to 250 of about 7,593 (278)

The reverberation suppression in wideband diver detection sonar

2014 Oceans - St. John's, 2014
The reverberation suppression is the foundation of target detection in diver detection sonar. The reverberation caused by the sea bottom is generally strong. Conventional methods with only amplitude cannot remove these reverberations completely because of the random temporal fluctuation of the signal amplitude, which causes false alarms especially in ...
Yang Juan, Xu Feng, Liu Jia, An Xudong, Ji Yongqiang   +4 more
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Lasso-based reverberation suppression in automatic speech Recognition

2015 IEEE International Conference on Acoustics, Speech and Signal Processing (ICASSP), 2015
Far-field automatic speech recognition (ASR) is challenging, mainly attributed to the high reverberation in the recordings. A novel linear sparse prediction model has been proposed to estimate and suppress reverberation. This model considers reverberation as a mixture of early and late reflections of the direct signal and estimates the late reflection ...
null Xuewei Zhang, null Yiye Lin, null Dong Wang   +2 more
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Reverberation suppression using dictionary learning in optical resolution photoacoustic microscopy

2017 IEEE International Ultrasonics Symposium (IUS), 2017
Photoacoustic Microscopy (PAM) offers a unique combination of high contrast from endogenous optical absorbers, and increased penetration to image microvasculature. However, images of the vasculature at increased depth are often corrupted by acoustic reverberation from superficial layers.
Sushanth Sathyanarayana, Bo Ning, Song Hu, John Hossack   +3 more
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A Hydrophone Perturbation Method for Reverberation Suppression

Journal of Information and Computational Science, 2014
Under the shallow sea condition, bottom reverberation is the main background noise. Especially the bottom and the buried targets echo are weak and signal-to-reverberation ratio is very low. So it is an important problem that how to improve the signal-to-reverberation ratio. This paper presents a method which is Perturbation Iteration Method. The method
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Space-time processing for suppression of bottom reverberation

Conference Record of The Twenty-Ninth Asilomar Conference on Signals, Systems and Computers, 2002
The major problem for sonars operating in shallow water is the detection of low Doppler targets in the presence of severe bottom reverberation. For a modern sonar with an azimuthally omni-directional transmitter; the Doppler of bottom reverberation is proportional to /spl nu/cos /spl theta/ where /spl nu/ is the speed of the sonar platform and /spl ...
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Adaptive Reverberation Suppression Techniques for SHM in Composite Materials

Structural Health Monitoring 2015, 2015
This paper introduces a new method for Structural Health Monitoring using error functions computed from guided waves reflected from damage. The approach is experimentally tested on anisotropic specimens such as composite plates. The baseline and test signals of each sensing path (between two PZT transducers) are measured and the energy of the scattered
VINICIUS ROSA, VICENTE LOPES, ERIC FLYNN, MICHAEL TODD, CHARLES FARRAR   +4 more
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Ocean reverberation suppressing by direct data domain based STAP

2012 IEEE 11th International Conference on Signal Processing, 2012
A class of direct data domain based space time adaptive processing (STAP) method for ocean reverberation suppressing is studied. The original direct data domain least square (D3LS) STAP does not use statistical information of the testing snapshot. This work proposes a new method named direct that the snapshot number has no effect on the performance of ...
Gao-xiang Xing, Zhi-ming Cai
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Reverberation characterization and suppression by means of principal components

IEEE Oceanic Engineering Society. OCEANS'98. Conference Proceedings (Cat. No.98CH36259), 2002
We apply the principal component inverse (PCI) method of rapidly adaptive interference suppression to the problem of separating the strong components of reverberation in an active reverberation experiment. A best low-rank estimate of a reverberation return is extracted by decomposing the returns into short duration subintervals over which the signal is
T.A. Palka, D.W. Tufts
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The bottom reverberation suppression algorithm for side scan sonar

2014 Oceans - St. John's, 2014
The sea bottom reverberation is one of the important problems, which restrict the bottom targets detection performance with the high frequency imaging sonar. In this paper, a bottom reverberation suppression algorithm is presented to improve the performance of the high frequency side scan sonar for small target detection.
Liu Jia, Xu Feng, Yang Juan, An Xudong
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Broadband DOA Estimation by Beamforming with Suppression of Reverberation

2008 Congress on Image and Signal Processing, 2008
Acoustic signal processing in shallow water environments is a challenging problem because of the presence of reverberation. Based on some models of reverberation, data from sensors array is pretreated to suppress reverberation. Considering reverberation as a sum of echoes of transmitted signal, the principal component inverse (PCI) algorithm is ...
Xuan Li, Xiaochuan Ma, Chaohuan Hou
openaire   +1 more source