Results 21 to 30 of about 7,633 (272)
Suppression of reverberation artifact by subtraction imaging [PDF]
The Journal of the Acoustical Society of America, 1990 Reverberations in ultrasound pulse-echo signals are the result of parallel specular reflectors that are perpendicular to the incident sound beam. The multiple reflections within the space between the reflectors cause a decaying pulse train of echoes to be superimposed on the returned echoes due to other structures. In a medical ultrasound B-scan, these
Terry A. Kling, K. Kirk Shung
openaire +1 more source
High-Resolution Wideband Waveform Design for Sonar Based on Multi-Parameter Modulation
Remote Sensing, 2023 The design of transmitting waveforms is an effective way to improve the detection performance of sonar systems. For the problem of high-range sidelobe when designing reverberation-resistant waveforms, this paper proposes a high-resolution wideband ...
Tong Duan +3 more
doaj +1 more source
Applied Sciences, 2021 The estimation of the late reverberant spectral variance (LRSV) is of paramount importance in most reverberation suppression algorithms. This letter proposes an improved single-channel LRSV estimator based on Habets LRSV estimator by using an adaptive ...
Zhaoqi Zhang, Xuelei Feng, Yong Shen
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The intermediate line region in active galactic nuclei [PDF]
, 2016 We show that the recently observed suppression of the gap between the broad line region (BLR) and the narrow line region (NLR) in some AGN can be fully explained by an increase of the gas density in the emitting region.
Adhikari, T. P. +4 more
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Reverberation Suppression in Echocardiography Using a Causal Convolutional Neural Network
IEEE Access, 2023 While ultrasound imaging has seen vast technical advances over the last decades, trans-thoracic echocardiography still suffers from image quality degradation caused by acoustic interaction with inhomogeneous tissue layers between the transducer and the ...
Tollef Struksnes Jahren +5 more
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Revealing the X-ray Variability of AGN with Principal Component Analysis [PDF]
, 2014 We analyse a sample of 26 active galactic nuclei with deep XMM-Newton observations, using principal component analysis (PCA) to find model independent spectra of the different variable components. In total, we identify at least 12 qualitatively different
Alston, W. +9 more
core +2 more sources
Reverberation suppression algorithm for LS beamforming based on Wiener post-filter
Dianzi Jishu Yingyong, 2018 Reverberation causes speech signal time and frequency to blur, and speech is difficult to understand when serious. In order to improve the speech quality, this paper presents a least squares beamforming reverberation suppression algorithm with Wiener ...
Zhang Xiuzai +3 more
doaj +1 more source
Sensors, 2023 Sidelobe suppression is a major challenge in wideband beamforming for acoustic research, especially in high noise and reverberation environments. In this paper, we propose a multi-objective NSGA-II wideband beamforming method based on a spherical ...
Zhenghong Liu +4 more
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Spherical microphone array acoustic rake receivers [PDF]
, 2015 Several signal independent acoustic rake receivers are proposed for speech dereverberation using spherical microphone arrays. The proposed rake designs take advantage of multipaths, by separately capturing and combining early reflections with the direct ...
Javed, HA, Moore, AH, Naylor, PA
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Model-based optimal action selection for Dyna-Q reverberation suppression cognitive sonar
EURASIP Journal on Advances in Signal Processing, 2023 The Doppler shift of low-speed targets is frequently disturbed by the reverberation Doppler spread clutter under the shallow sea. The clutter is generated by underwater scatterers, which increases the difficulty of Doppler estimation.
Yubin Fu +4 more
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