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2024 OES China Ocean Acoustics, COA 2024

作者： Yang, Wang Yan-Sen, L.I.U. Feng-Ming, W.U. Dalian Scientific Test and Control Technology Institute Science and Technology on Underwater Test and Control Laboratory Dalian China

ISBN: (纸本)9798350340297

To enhance the unsteady narrowband spectrum of ship noise, an unsteady narrowband stochastic resonance processing method based on particle swarm optimization (PSO) was proposed. The method adopts a bistable stochastic resonance model and takes the mean signal-to-noise ratio in the narrowband bandwidth as the fitness function;it can perform adaptive optimal selection of system parameters matching the narrowband spectrum and background noise and can enhance the narrowband spectrum signal. According to the flow of the algorithm, the simulated unsteady narrowband spectrum and the measured ship noise data are processed and analyzed. The results show that this method can easily adapt to the characteristics of the narrowband ship spectrum and enhances a weak narrowband spectrum;it has broad research prospects and good application value. © 2024 IEEE.

关键词： Circuit resonance

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Simulation of Vertical Highlight Distribution of underwater Objects Based on Virtual Extended Arrays

Simulation of Vertical Highlight Distribution of Underwater ...

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2024 OES China Ocean Acoustics, COA 2024

作者： Zhang, Yang Li, Guijuan Wang, Rui Liu, Wenhao Wang, Jingying Jia, Bing Dalian Scientific Test and Control Technology Institute Science and Technology on Underwater Test and Control Laboratory Dalian China

ISBN: (纸本)9798350340297

To study the vertical distribution characteristics of object echo in water, a simulation method based on a large-aperture virtual extended array is proposed. The proposed method adopts the near-field plate element method to predict the object echo waveform at the array end and takes advantage of the high resolution of the large aperture virtual extended array beam. Two-dimensional acoustic images of the object, such as the horizontal-vertical direction, horizontal distance, and range vertical, are obtained. The results show that the object echo highlights of the single-layer shell are obtained three parts of the boat: the hull, shell, and stern, and the vertical distribution characteristics reflect the vertical position relationship of the three parts. The formation mechanism of the echo highlights includes the smooth surface echo of a large area in the hull, hull, and other parts, and the angular wave at the joint of the hull and hull and the hull and stern. © 2024 IEEE.

关键词： Digital elevation model

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Vertical Array Cable Jitter Noise Suppression Method using Frequency Vertical Wavenumber Spectral Filtering

Vertical Array Cable Jitter Noise Suppression Method using F...

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2024 OES China Ocean Acoustics, COA 2024

作者： Li, Peng Che, Shuwei Liu, Yu Zhao, Xingchen Science and Technology on Underwater Test and Control Laboratory Dalian Scientific Test and Control Technology Institute Dalian China

ISBN: (纸本)9798350340297

The proposed method suppresses low-frequency cable vibration noise in a vertical array acoustic observation system using the frequency vertical wavenumber spectrum. Initially, the frequency wavenumber spectrum is extracted from the data collected from the vertical array via vertical wavenumber-depth transformation. A frequency wavenumber domain filter is designed according to the sound wave speed in the cable, and cable interference is filtered out. The signal is restored via vertical wavenumber-depth inverse transformation. The simulation results show that under the simulation conditions described herein, low-frequency line spectra such as 30 and 60 Hz can achieve a signal-to-noise ratio improvement of >1.2dB. © 2024 IEEE.

关键词： Signal to noise ratio

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Research on numerical simulation of tandem thrusters flow-induced noise 2

Research on numerical simulation of tandem thrusters flow-in...

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2023 2nd International Conference on Acoustics, Fluid Mechanics and Engineering, AFME 2023

作者： Ma, Fuqiang Xie, Lixun Liu, Yansen Science and Technology on Underwater Test and Control Laboratory Liaoning Dalian116013 China

A tandem propeller is a kind of propulsion device that is installed on the outer axis and the inner axis with the same axis respectively and rotates positively and negatively. Taking DTMB tandem thrusters as an example, which consists of propeller3689 and propeller3849, the hydrodynamic characteristic simulation of the tandem thrusters is completed, using sound analogy theory. The simulation results are consistent with the experimental results. The speed distribution of the tandem thrusters and the hydrodynamic wake of the tandem thrusters are analyzed. Through the analysis of acoustic radiation characteristics, it can be concluded that the noise characteristics of tandem thrusters are more complex than those of ordinary propellers, and there are more line spectrum characteristics in them. © Published under licence by IOP Publishing Ltd.

关键词： Propellers

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Estimation of target depth using deep-sea echo multipath structure matching

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Chinese Journal of Acoustics 2023年第3期42卷 251-269页

作者： ZHANG Fengzhen LI Guijuan HU Wenshuai HU Chen Key Laboratory of Science and Technology on Underwater Test and Control Dalian 116013 Dalian Scientific Test and Control Technology Institute Dalian 116013

This paper presents a method to estimate the depth of deep-sea target by matching the time delay and amplitude structure of echo multipath highlight *** echo structure is the convolution of two-way channel transfer function as well as the acoustic scattering function of the target,which shows the characteristics of deep-sea highlight clusters when the target is close to the sea surface or near the sea *** time delay and amplitude structure of highlight clusters are related to the target depth,which can be used to estimate the target depth.A method of matching estimation of target depth on range-depth grid using nonlinear programming cost function is *** mismatch effects of inter-cluster time delay interval deviation and sea water sound velocity profile deviation on matching estimation are simulated and *** results of a winter experiment in the South China Sea illustrate that when the water depth is 1 km and distance is 5–8 km,the echo of target is 40 m underwater,there are three highlight clusters with a time interval of about 0.3 s,with the error range of target depth matching estimation being 0–65 m.

关键词： matching structure estimation

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Modeling of Ship Target Radiated Noise Spectrum Characteristics 3

Modeling of Ship Target Radiated Noise Spectrum Characterist...

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3rd International Symposium on Computer technology and Information science, ISCTIS 2023

作者： Yang, Xuemeng Science and Technology on Underwater Test and Control Laboratory Dalian China

ISBN: (纸本)9798350325386

This paper presents a comprehensive methodology for modeling ship target radiated noise spectrum characteristics, addressing the challenges of limited data availability. The proposed methodology includes data collection, preprocessing, feature extraction, and selection, along with the development of a noise spectrum model using advanced statistical techniques. Experimental evaluations using real-world ship noise data confirm the effectiveness of the proposed methodology in accurately capturing ship target radiated noise spectra. The findings have implications for underwater acoustic analysis and naval applications. © 2023 IEEE.

关键词： underwater acoustics

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underwater Transient Noise Duration Estimation Method Based on the Page test

Underwater Transient Noise Duration Estimation Method Based ...

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2024 OES China Ocean Acoustics, COA 2024

作者： Zhang, Qin-Chuan Liu, Yan-Sen Yang, Wang Dalian Scientific Test and Control Technology Institute Dalian China Dalian Scientific Test and Control Technology Institute Science and Technology on Underwater Test and Control Laboratory Dalian China

ISBN: (纸本)9798350340297

The underwater transient noise radiated by ships provides rich target information and is the focus of target acoustic characteristics analysis. The duration is a crucial representation parameter of the time-domain envelope. The Page test is an effective method for detecting transients, as it can be used to estimate the starting time of the transient. Hence, in this study, the ending time of the transient is estimated by performing time-domain reversal on the signal. In addition, in a low-signal-to-noise ratio environment, wavelet noise reduction pre-processing is introduced to improve the estimation effect and then to estimate the duration of transient noise. The simulation verification results reveal that this method can accurately estimate the duration of underwater transient noise and can also ensure high accuracy in low-signal-to-noise ratio environments. © 2024 IEEE.

关键词： Electromagnetic transients

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Ship Target Radiated Noise Modulation Spectrum Processing: Integration with Deep Learning Methods

Ship Target Radiated Noise Modulation Spectrum Processing: I...

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2023 International Conference on Algorithms, High Performance Computing, and Artificial Intelligence, AHPCAI 2023

作者： Mu, Lin Science and Technology on Underwater Test and Control Laboratory Dalian China

ISBN: (纸本)9781510671881

The modulation spectrum processing of ship target radiated noise is an important means of detecting, tracking, and recognizing targets in naval operations. Improving the processing performance of modulation spectrum is crucial for enhancing naval combat capabilities. This paper combines traditional modulation spectrum processing methods with deep learning methods and proposes a modulation spectrum feature enhancement method based on deep learning. The experimental results show that, the method can effectively improve the clarity and extraction quality of the line spectrum in the modulation spectrum time-frequency map. © 2023 SPIE. All rights reserved.

关键词： Deep learning

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Research on an Accurate Passive Location Algorithm Based on the underwater Target Acoustic-Magnetic Fusion in the Near Field

Research on an Accurate Passive Location Algorithm Based on ...

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2022 International Conference on Signal Processing and Communication technology, SPCT 2022

作者： Zhai, Chunping Yang, Shanshan Zhang, Yu Zhang, Liang Science and Technology on Underwater Test and Control Laboratory Dalian Scientific Test and Control Technology Institute Dalian China

ISBN: (纸本)9781510664333

The passive localization of the underwater target is conducive to accurately track the underwater target and obtain their radiation characteristics. While, in practical application, the algorithm is affected by many uncertain factors. Such as the target strength, complex shallow water environment, input parameters and so on. So, the robustness of ultra-short-range localization performance is relatively poor. The passive location algorithm of magnetic field based on field modeling and optimized search method is not affected by the adverse factors such as shallow water environment and acoustic array. It can achieve high-precision location performance. The location accuracy is about 0.1 time of the ship's length. However, due to the influence of the fast attenuation of magnetic field, this algorithm can only realize the precise positioning of ultra-short-range and high stability according to the magnitude of magnetic field. This paper attempts to take advantage of the focused beamforming location algorithm and magnetic field high robustness positioning algorithm for the first time. And the adaptive filtering algorithm is adopted to effectively process the passive localization of acoustic and magnetic field results, so as to overcome the adverse effect of the conical ambiguity surface of scalar acoustic array on focused beamforming acoustic image passive location algorithm, and realize high precision and high stability passive localization results of the ship in near-field online. © 2023 SPIE.

关键词： Magnetic fields

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Sea Clutter Measurement test and Amplitude Characteristics Analysis in the South China Sea Nearshore Area

Sea Clutter Measurement Test and Amplitude Characteristics A...

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2022 International Conference on Information Processing in Ocean science and technology, ICIPOST 2022

作者： Zhao, X. Han, J. Zhang, X. Zhang, J. Li, P. Science and Technology on Underwater Test and Control Laboratory Dalian116013 China

To address the problem of sea clutter amplitude distribution characteristics varying with bandwidth, this paper obtains the raw data of clutter under different polarization methods of HH and VV in X and Ka bands based on the sea clutter measurement experiment carried out in June 2022 in the near-shore waters of South China Sea. For the data in X-band HH polarization mode, the goodness-of-fit test was conducted based on the classical models of Rayleigh, Weibull, log-normal and K distribution for the amplitude distribution characteristics of the sea clutter, and the variation of the estimated parameters of the distribution model with the bandwidth was analyzed. The test data show that: 1, with the increase of bandwidth sea clutter amplitude decreases;2, with the increase of bandwidth Weibull distribution model parameters are decreasing trend, k distribution parameters are increasing trend;3, the test conditions, the offshore sea clutter amplitude distribution is the optimal K distribution. The conclusions of this paper can provide a comparison and reference for the subsequent study on the characteristics of sea clutter distribution. © Published under licence by IOP Publishing Ltd.

关键词： Bandwidth

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