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Detection and Feature Extraction in Acoustic Sensor Signals

A special issue of Sensors (ISSN 1424-8220). This special issue belongs to the section "Physical Sensors".

Deadline for manuscript submissions: closed (20 August 2023) | Viewed by 24328

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Special Issue Editors

School of Automation and Information Engineering, Xi’an University of Technology, Xi’an 710048, China
Interests: fractal dimension; underwater signal processing; sensor signal processing; denoising; feature extraction; fault diagnosis; image processing
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Guest Editor
Institute of Chemical and Physical Processes of National Research Council, Via G. Moruzzi 1, 56124 Pisa, Italy
Interests: environmental acoustics; noise mitigations; noise management; noise measurements; noise mapping; noise action plans; wind turbine noise; road traffic noise; railway noise; airport noise
Special Issues, Collections and Topics in MDPI journals

Special Issue Information

Dear Colleagues,

Acoustic sensors have an extremely wide range of applications in many fields, including underwater acoustics, architectural acoustics, engineering acoustics, physical acoustics, environmental acoustics, psychoacoustics, and so on. The signals collected by high-sensitivity acoustic sensors contain a large amount of valid information that facilitates further processing of the collected acoustic signals. In particular, detection and feature extraction, as two important measures of acoustic sensor signal processing, can capture more information about the target and extract features with separability.

Various trends indicate that detection as well as feature extraction play an increasingly important role in the processing of acoustic sensor signals, and the latest methods for acoustic signal detection or feature extraction are welcome in this Special Issue, such as the application of stochastic resonance in vibration signals, nonlinear feature extraction of underwater acoustic signals, and so on. We encourage all authors working on similar topics to submit their work to this Special Issue. Equally welcome are contributions from any field of acoustic sensors with applications in real-world data.

Dr. Yuxing Li
Dr. Luca Fredianelli
Guest Editors

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Keywords

  • acoustic sensor signal feature extraction
  • acoustic sensor signal detection
  • acoustic sensor signal processing
  • stochastic resonance in vibration signals
  • nonlinear feature extraction of underwater acoustic signals
  • heart rate state detection
  • acoustic beamforming and the emerging field of acoustic cameras

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Published Papers (12 papers)

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Editorial

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2 pages, 163 KiB  
Editorial
Detection and Feature Extraction in Acoustic Sensor Signals
by Yuxing Li and Luca Fredianelli
Sensors 2023, 23(19), 8030; https://doi.org/10.3390/s23198030 - 22 Sep 2023
Viewed by 1298
Abstract
Our advances in detection and feature extraction in the processing of acoustic signals allow us to capture more information about a target and extract features with separability [...] Full article
(This article belongs to the Special Issue Detection and Feature Extraction in Acoustic Sensor Signals)

Research

Jump to: Editorial

15 pages, 736 KiB  
Article
An Intelligent Cost-Reference Particle Filter with Resampling of Multi-Population Cooperation
by Xinyu Zhang, Mengjiao Ren, Jiemin Duan, Yingmin Yi, Biyu Lei and Shuyue Wu
Sensors 2023, 23(14), 6603; https://doi.org/10.3390/s23146603 - 22 Jul 2023
Cited by 2 | Viewed by 1080
Abstract
Although the cost-reference particle filter (CRPF) has a good advantage in solving the state estimation problem with unknown noise statistical characteristics, its estimation accuracy is still affected by the lack of particle diversity and sensitivity to the particles’ initial value. In order to [...] Read more.
Although the cost-reference particle filter (CRPF) has a good advantage in solving the state estimation problem with unknown noise statistical characteristics, its estimation accuracy is still affected by the lack of particle diversity and sensitivity to the particles’ initial value. In order to solve these problems of the CRPF, this paper proposed an intelligent cost-reference particle filter algorithm based on multi-population cooperation. A multi-population cooperative resampling strategy based on ring structure was designed. The particles were divided into multiple independent populations upon initialization, and each population generated particles with a different initial distribution. The particles in each population were divided into three different particle sets with high, medium and low weights by the golden section ratio according to the weight. The particle sets with high and medium weights were retained. Then, a cooperative strategy based on Gaussian mutation was designed to resample the low-weight particle set of each population. The high-weight particles of the previous population in the ring structure were randomly selected for Gaussian mutation to replace the low-weight particles in the current population. The low-weight particles of all populations were resampled in turn. The simulation results show that the intelligent CRPF based on multi-population cooperation proposed in this paper can reduce the sensitivity of the CRPF to the particles’ initial value and improve the particle diversity in resampling. Compared with the general CRPF and intelligent CRPF with adaptive MH resampling (MH-CRPF), the RMSE and MAE of the proposed method are lower. Full article
(This article belongs to the Special Issue Detection and Feature Extraction in Acoustic Sensor Signals)
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24 pages, 7948 KiB  
Article
Bearing Fault-Detection Method Based on Improved Grey Wolf Algorithm to Optimize Parameters of Multistable Stochastic Resonance
by Weichao Huang and Ganggang Zhang
Sensors 2023, 23(14), 6529; https://doi.org/10.3390/s23146529 - 19 Jul 2023
Cited by 6 | Viewed by 1502
Abstract
In an effort to overcome the problem that the traditional stochastic resonance system cannot adjust the structural parameters adaptively in bearing fault-signal detection, this article proposes an adaptive-parameter bearing fault-detection method. First of all, the four strategies of Sobol sequence initialization, exponential convergence [...] Read more.
In an effort to overcome the problem that the traditional stochastic resonance system cannot adjust the structural parameters adaptively in bearing fault-signal detection, this article proposes an adaptive-parameter bearing fault-detection method. First of all, the four strategies of Sobol sequence initialization, exponential convergence factor, adaptive position update, and Cauchy–Gaussian hybrid variation are used to improve the basic grey wolf optimization algorithm, which effectively improves the optimization performance of the algorithm. Then, based on the multistable stochastic resonance model, the structure parameters of the multistable stochastic resonance are optimized through improving the grey wolf algorithm, so as to enhance the fault signal and realize the effective detection of the bearing fault signal. Finally, the proposed bearing fault-detection method is used to analyze and diagnose two open-source bearing data sets, and comparative experiments are conducted with the optimization results of other improved algorithms. Meanwhile, the method proposed in this paper is used to diagnose the fault of the bearing in the lifting device of a single-crystal furnace. The experimental results show that the fault frequency of the inner ring of the first bearing data set diagnosed using the proposed method was 158 Hz, and the fault frequency of the outer ring of the second bearing data set diagnosed using the proposed method was 162 Hz. The fault-diagnosis results of the two bearings were equal to the results derived from the theory. Compared with the optimization results of other improved algorithms, the proposed method has a faster convergence speed and a higher output signal-to-noise ratio. At the same time, the fault frequency of the bearing of the lifting device of the single-crystal furnace was effectively diagnosed as 35 Hz, and the bearing fault signal was effectively detected. Full article
(This article belongs to the Special Issue Detection and Feature Extraction in Acoustic Sensor Signals)
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19 pages, 4526 KiB  
Article
Intelligent Diagnosis of Rolling Bearings Fault Based on Multisignal Fusion and MTF-ResNet
by Kecheng He, Yanwei Xu, Yun Wang, Junhua Wang and Tancheng Xie
Sensors 2023, 23(14), 6281; https://doi.org/10.3390/s23146281 - 10 Jul 2023
Cited by 6 | Viewed by 1575
Abstract
Existing diagnosis methods for bearing faults often neglect the temporal correlation of signals, resulting in easy loss of crucial information. Moreover, these methods struggle to adapt to complex working conditions for bearing fault feature extraction. To address these issues, this paper proposes an [...] Read more.
Existing diagnosis methods for bearing faults often neglect the temporal correlation of signals, resulting in easy loss of crucial information. Moreover, these methods struggle to adapt to complex working conditions for bearing fault feature extraction. To address these issues, this paper proposes an intelligent diagnosis method for compound faults in metro traction motor bearings. This method combines multisignal fusion, Markov transition field (MTF), and an optimized deep residual network (ResNet) to enhance the accuracy and effectiveness of diagnosis in the presence of complex working conditions. At the outset, the acquired vibration and acoustic emission signals are encoded into two-dimensional color feature images with temporal relevance by Markov transition field. Subsequently, the image features are extracted and fused into a set of comprehensive feature images with the aid of the image fusion framework based on a convolutional neural network (IFCNN). Afterwards, samples representing different fault types are presented as inputs to the optimized ResNet model during the training phase. Through this process, the model’s ability to achieve intelligent diagnosis of compound faults in variable working conditions is realized. The results of the experimental analysis verify that the proposed method can effectively extract comprehensive fault features while working in complex conditions, enhancing the efficiency of the detection process and achieving a high accuracy rate for the diagnosis of compound faults. Full article
(This article belongs to the Special Issue Detection and Feature Extraction in Acoustic Sensor Signals)
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18 pages, 4975 KiB  
Article
A Dual-Optimization Fault Diagnosis Method for Rolling Bearings Based on Hierarchical Slope Entropy and SVM Synergized with Shark Optimization Algorithm
by Yuxing Li, Bingzhao Tang, Bo Huang and Xiaohui Xue
Sensors 2023, 23(12), 5630; https://doi.org/10.3390/s23125630 - 16 Jun 2023
Cited by 5 | Viewed by 1543
Abstract
Slope entropy (SlopEn) has been widely applied in fault diagnosis and has exhibited excellent performance, while SlopEn suffers from the problem of threshold selection. Aiming to further enhance the identifying capability of SlopEn in fault diagnosis, on the basis of SlopEn, the concept [...] Read more.
Slope entropy (SlopEn) has been widely applied in fault diagnosis and has exhibited excellent performance, while SlopEn suffers from the problem of threshold selection. Aiming to further enhance the identifying capability of SlopEn in fault diagnosis, on the basis of SlopEn, the concept of hierarchy is introduced, and a new complexity feature, namely hierarchical slope entropy (HSlopEn), is proposed. Meanwhile, to address the problems of the threshold selection of HSlopEn and a support vector machine (SVM), the white shark optimizer (WSO) is applied to optimize both HSlopEn and an SVM, and WSO-HSlopEn and WSO-SVM are proposed, respectively. Then, a dual-optimization fault diagnosis method for rolling bearings based on WSO-HSlopEn and WSO-SVM is put forward. We conducted measured experiments on single- and multi-feature scenarios, and the experimental results demonstrated that whether single-feature or multi-feature, the WSO-HSlopEn and WSO-SVM fault diagnosis method has the highest recognition rate compared to other hierarchical entropies; moreover, under multi-features, the recognition rates are all higher than 97.5%, and the more features we select, the better the recognition effect. When five nodes are selected, the highest recognition rate reaches 100%. Full article
(This article belongs to the Special Issue Detection and Feature Extraction in Acoustic Sensor Signals)
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14 pages, 3314 KiB  
Article
Deconvolved Fractional Fourier Domain Beamforming for Linear Frequency Modulation Signals
by Zhuoran Liu, Quan Tao, Wanzhong Sun and Xiaomei Fu
Sensors 2023, 23(7), 3511; https://doi.org/10.3390/s23073511 - 27 Mar 2023
Cited by 2 | Viewed by 1448
Abstract
To estimate the direction of arrival (DOA) of a linear frequency modulation (LFM) signal in a low signal-to-noise ratio (SNR) hydroacoustic environment by a small aperture array, a novel deconvolved beamforming method based on fractional Fourier domain delay-and-sum beamforming (FrFB) was proposed. Fractional [...] Read more.
To estimate the direction of arrival (DOA) of a linear frequency modulation (LFM) signal in a low signal-to-noise ratio (SNR) hydroacoustic environment by a small aperture array, a novel deconvolved beamforming method based on fractional Fourier domain delay-and-sum beamforming (FrFB) was proposed. Fractional Fourier transform (FrFT) was used to convert the received signal into the fractional Fourier domain, and delay-and-sum beamforming was subsequently performed. Noise resistance was acquired by focusing the energy of the LFM signal distributed in the time–frequency domain. Then, according to the convolution structure of the FrFB complex output, the influence of the fractional Fourier domain complex beam pattern was removed by deconvolution, and the target spatial distribution was restored. Therefore, an improved spatial resolution of DOA estimation was obtained without increasing the array aperture. The simulation and experimental results show that, with a small aperture array at low SNR, the proposed method possesses higher spatial resolution than FrFB and frequency-domain deconvolved conventional beamforming. Full article
(This article belongs to the Special Issue Detection and Feature Extraction in Acoustic Sensor Signals)
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20 pages, 5207 KiB  
Article
Leaky Partial Update LMS Algorithms in Application to Structural Active Noise Control
by Dariusz Bismor
Sensors 2023, 23(3), 1169; https://doi.org/10.3390/s23031169 - 19 Jan 2023
Cited by 5 | Viewed by 1776
Abstract
Adaptive signal processing algorithms play an important role in many practical applications in diverse fields, such as telecommunication, radar, sonar, multimedia, biomedical engineering and noise control. Recently, a group of adaptive filtering algorithms called partial update adaptive algorithms (partial updates) has gathered considerable [...] Read more.
Adaptive signal processing algorithms play an important role in many practical applications in diverse fields, such as telecommunication, radar, sonar, multimedia, biomedical engineering and noise control. Recently, a group of adaptive filtering algorithms called partial update adaptive algorithms (partial updates) has gathered considerable attention in both research and practical applications. This paper is a study of the application of PUs to very demanding, structural active noise control (ANC) systems, which are of particular interest due to their ability to provide for a global noise reduction. However, such systems are multichannel, with very high computational power requirements, which may be reduced by the application of partial updates. The paper discusses the modifications necessary to apply PUs in structural ANC systems and the potential computational power savings offered by this application. As a result, leaky versions of the PU LMS algorithms are introduced to the general public. The paper also presents two simulation examples, based on real laboratory setups, confirming high performance of the proposed algorithms. Full article
(This article belongs to the Special Issue Detection and Feature Extraction in Acoustic Sensor Signals)
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18 pages, 2443 KiB  
Article
Statistical Pass-By for Unattended Road Traffic Noise Measurement in an Urban Environment
by Elena Ascari, Mauro Cerchiai, Luca Fredianelli and Gaetano Licitra
Sensors 2022, 22(22), 8767; https://doi.org/10.3390/s22228767 - 13 Nov 2022
Cited by 26 | Viewed by 2556
Abstract
Low-noise surfaces have become a common mitigation action in the last decade, so much so that different methods for feature extraction have been established to evaluate their efficacy. Among these, the Close Proximity Index (CPX) evaluates the noise emissions by means of multiple [...] Read more.
Low-noise surfaces have become a common mitigation action in the last decade, so much so that different methods for feature extraction have been established to evaluate their efficacy. Among these, the Close Proximity Index (CPX) evaluates the noise emissions by means of multiple runs at different speeds performed with a vehicle equipped with a reference tire and with acoustic sensors close to the wheel. However, signals acquired with CPX make it source oriented, and the analysis does not consider the real traffic flow of the studied site for a receiver-oriented approach. These aspects are remedied by Statistical Pass-By (SPB), a method based on sensor feature extraction with live detection of events; noise and speed acquisitions are performed at the roadside in real case scenarios. Unfortunately, the specific SPB requirements for its measurement setup do not allow an evaluation in urban context unless a special setup is used, but this may alter the acoustical context in which the measurement was performed. The present paper illustrates the testing and validation of a method named Urban Pass-By (U-SPB), developed during the LIFE NEREiDE project. U-SPB originates from standard SPB, exploits unattended measurements and develops an in-lab feature detection and extraction procedure. The U-SPB extends the evaluation in terms of before/after data comparison of the efficiency of low-noise laying in an urban context while combining the estimation of long-term noise levels and traffic parameters for other environmental noise purposes, such as noise mapping and action planning. Full article
(This article belongs to the Special Issue Detection and Feature Extraction in Acoustic Sensor Signals)
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16 pages, 37874 KiB  
Article
Optimization Algorithm for Delay Estimation Based on Singular Value Decomposition and Improved GCC-PHAT Weighting
by Shizhe Wang, Zongji Li, Pingbo Wang and Huadong Chen
Sensors 2022, 22(19), 7254; https://doi.org/10.3390/s22197254 - 24 Sep 2022
Cited by 6 | Viewed by 1979
Abstract
The accuracy of time delay estimation seriously affects the accuracy of sound source localization. In order to improve the accuracy of time delay estimation under the condition of low SNR, a delay estimation optimization algorithm based on singular value decomposition and improved GCC [...] Read more.
The accuracy of time delay estimation seriously affects the accuracy of sound source localization. In order to improve the accuracy of time delay estimation under the condition of low SNR, a delay estimation optimization algorithm based on singular value decomposition and improved GCC-PHAT weighting (GCC-PHAT-ργ weighting) is proposed. Firstly, the acoustic signal collected by the acoustic sensor array is subjected to singular value decomposition and noise reduction processing to improve the signal-to-noise ratio of the signal; then, the cross-correlation operation is performed, and the cross-correlation function is processed by the GCC-PHAT-ργ weighting method to obtain the cross-power spectrum; finally, the inverse transformation is performed to obtain the generalized correlation time domain function, and the peak detection is performed to obtain the delay difference. The experiment was carried out in a large outdoor pool, and the experimental data were processed to compare the time delay estimation performance of three methods: GCC-PHAT weighting, SVD-GCC-PHAT weighting (meaning: GCC-PHAT weighting based on singular value decomposition) and SVD-GCC-PHAT-ργ weighting (meaning: GCC-PHAT-ργ weighting based on singular value decomposition). The results show that the delay estimation optimization algorithm based on SVD-GCC-PHAT-ργ improves the delay estimation accuracy by at least 37.95% compared with the other two methods. The new optimization algorithm has good delay estimation performance. Full article
(This article belongs to the Special Issue Detection and Feature Extraction in Acoustic Sensor Signals)
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15 pages, 3378 KiB  
Article
A Time-of-Flight Estimation Method for Acoustic Ranging and Thermometry Based on Digital Lock-In Filtering
by Qi Liu, Bin Zhou, Jianyong Zhang, Ruixue Cheng, Xuhao Zhao, Rong Zhao, Minglu Dai, Bubin Wang and Yihong Wang
Sensors 2022, 22(15), 5519; https://doi.org/10.3390/s22155519 - 24 Jul 2022
Cited by 6 | Viewed by 1665
Abstract
Accurate ranging and real-time temperature monitoring are essential for metrology and safety in electrical conduit applications. This paper proposes an acoustic time-of-flight (TOF) estimation method based on the digital lock-in filtering (DLF) technique for conduit ranging and thermometry. The method establishes the relationship [...] Read more.
Accurate ranging and real-time temperature monitoring are essential for metrology and safety in electrical conduit applications. This paper proposes an acoustic time-of-flight (TOF) estimation method based on the digital lock-in filtering (DLF) technique for conduit ranging and thermometry. The method establishes the relationship between the frequency and the time domain by applying a linear frequency modulated Chirp signal as the sound source and using the DLF technique to extract the first harmonic of the characteristic frequencies of the transmitted and received signals. Acoustic TOF estimation in the conduit is then achieved by calculating the mathematical expectation of the time difference between each characteristic frequency in the time-frequency relationship of the two signals. The experimental results with enhanced noise interference on different conduit lengths and various temperature conditions, proved that the proposed DLF method can establish a robust linear time-frequency relationship according to the characteristics of the Chirp signal, and the measurement accuracy of TOF has also been confirmed. Compared to the conventional method, the DLF method provides the lowest absolute error and standard deviation for both distance and temperature measurements with an enhanced robustness. Full article
(This article belongs to the Special Issue Detection and Feature Extraction in Acoustic Sensor Signals)
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19 pages, 3795 KiB  
Article
A Novel Deep-Learning Method with Channel Attention Mechanism for Underwater Target Recognition
by Lingzhi Xue, Xiangyang Zeng and Anqi Jin
Sensors 2022, 22(15), 5492; https://doi.org/10.3390/s22155492 - 23 Jul 2022
Cited by 19 | Viewed by 2698
Abstract
The core of underwater acoustic recognition is to extract the spectral features of targets. The running speed and track of the targets usually result in a Doppler shift, which poses significant challenges for recognizing targets with different Doppler frequencies. This paper proposes deep [...] Read more.
The core of underwater acoustic recognition is to extract the spectral features of targets. The running speed and track of the targets usually result in a Doppler shift, which poses significant challenges for recognizing targets with different Doppler frequencies. This paper proposes deep learning with a channel attention mechanism approach for underwater acoustic recognition. It is based on three crucial designs. Feature structures can obtain high-dimensional underwater acoustic data. The feature extraction model is the most important. First, we develop a ResNet to extract the deep abstraction spectral features of the targets. Then, the channel attention mechanism is introduced in the camResNet to enhance the energy of stable spectral features of residual convolution. This is conducive to subtly represent the inherent characteristics of the targets. Moreover, a feature classification approach based on one-dimensional convolution is applied to recognize targets. We evaluate our approach on challenging data containing four kinds of underwater acoustic targets with different working conditions. Our experiments show that the proposed approach achieves the best recognition accuracy (98.2%) compared with the other approaches. Moreover, the proposed approach is better than the ResNet with a widely used channel attention mechanism for data with different working conditions. Full article
(This article belongs to the Special Issue Detection and Feature Extraction in Acoustic Sensor Signals)
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14 pages, 5303 KiB  
Article
Study on a Detection Technique for Scholte Waves at the Seafloor
by Minshuai Liang, Liang Wang, Gaokun Yu, Yun Ren and Linhui Peng
Sensors 2022, 22(14), 5344; https://doi.org/10.3390/s22145344 - 18 Jul 2022
Cited by 3 | Viewed by 1906
Abstract
Scholte waves at the seafloor have significant potential for underwater detection and communication, so a study about detecting Scholte waves is very meaningful in practice. In this paper, the detection of Scholte waves at the seafloor is researched theoretically and experimentally. Acoustic models [...] Read more.
Scholte waves at the seafloor have significant potential for underwater detection and communication, so a study about detecting Scholte waves is very meaningful in practice. In this paper, the detection of Scholte waves at the seafloor is researched theoretically and experimentally. Acoustic models with the multilayer elastic bottom are established according to the ocean environment, and a tank experiment is designed and carried out to detect Scholte waves. Different from detecting Scholte waves in the seismic wavefield, a technique for detecting Scholte waves in the sound pressure field is proposed in this paper. The experimental results show that the proposed technique can detect Scholte waves effectively, and there are no problems such as seabed coupling and the effect of wave speeds. Furthermore, the results also show that this detection technique is still effective in conditions with a sediment layer. The existence of sediment layers changes the acoustic field conditions and affects the excitation of Scholte waves. Full article
(This article belongs to the Special Issue Detection and Feature Extraction in Acoustic Sensor Signals)
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