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2020 IEEE International Conference on Advances in Electrical Engineering and Computer Applications, AEECA 2020

作者： Wang, Peibing Peng, Yuan Science and Technology on Underwater Test and Control Laboratory Dalian China

ISBN: (纸本)9781728165202

underwater acoustic target recognition technology is an important support technology for underwater acoustic information acquisition and underwater acoustic information confrontation. Its core includes target feature extraction and classification recognition. In this paper, deep convolution neural network is applied to feature extraction and classification of underwater acoustic target signal based on LOFAR spectrum. Firstly, the extraction method and preprocessing of LOFAR spectral features are introduced. Then, the applicability of deep convolution neural network in feature extraction and LOFAR spectrum of underwater acoustic target signal is briefly analyzed. Finally, the model construction and parameter optimization method of deep convolution neural network are explained in detail. Through analysis and research, this method has good applicability in the field of underwater acoustic target recognition. © 2020 IEEE.

关键词： Feature extraction

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Research on underwater acoustic target recognition based on LOFAR spectrum and deep learning method 5

Research on underwater acoustic target recognition based on ...

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5th International Conference on Automation, control and Robotics Engineering, CACRE 2020

作者： Wang, Peibing Peng, Yuan Science and Technology on Underwater Test and Control Laboratory Dalian China

ISBN: (纸本)9781728198880

underwater acoustic target recognition has long been an internationally recognized problem. This paper combines the method based on LOFAR spectrogram and the deep convolutional neural network of deep learning hot spot method for underwater target radiated noise recognition, making full use of the separability information of target noise in different dimensions, and using the time spectrum chart as the depth Learn to enter data. In this paper, the basic principle and specific application process of the method are analyzed in detail, and the measured data are simulated and classified, and the simulation diagram and test results are given. The results show that the recognition rate of underwater target recognition with this method is high. © 2020 IEEE.

关键词： Convolutional neural networks

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Echo Highlight Model of underwater Target and Design of FPGA Signal Simulation Module 5

Echo Highlight Model of Underwater Target and Design of FPGA...

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5th International Conference on Communication, Image and Signal Processing, CCISP 2020

作者： Chen, Hu Fengzhen, Zhang Zhaohui, Zhang Yuan, Peng Yi, Jiang Science and Technology on Underwater Test and Control Laboratory Dalian China

ISBN: (纸本)9781728185897

The rapid development of FPGA provides a new platform for target signal simulation. In this paper, we first analyze the mathematical model of underwater target echo highlights, and then design a set of signal generating module based on FPGA, which can simulate the target echo signal under specific target characteristics according to the preset highlight table and copy signal. With 5° as the unit, the angle of incidence is switched between 0°-180° by using the mechanical keys. The angle can be displayed in real time through the digital tube. The output signal can be directly connected to the transducer and power amplifier to achieve a specific sound source level. Finally, the signal acquisition test of the simulation module is carried out. 37 angles in the range of 0°-180° were collected and analyzed. The distribution of echo highlights was compared with the table of highlights after matched filter. The module's performance meets the expectation. © 2020 IEEE.

关键词： Field programmable gate arrays (FPGA)

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Experimental Study on Direction of Arrival Estimation of Acoustic Signals Based on Hyperbeam Cross Spectrum

Experimental Study on Direction of Arrival Estimation of Aco...

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2020 IEEE International Conference on Signal Processing, Communications and Computing, ICSPCC 2020

作者： Mingwei, Zhang Chunping, Zhai Yansen, Liu Shuwei, Che Science and Technology on Underwater Test and Control Laboratory Dalian China

ISBN: (纸本)9781728172019

The direction of arrival estimation(DOA) technology plays an important role in acoustic beacon fast search and rescue at sea. In this paper, the DOA resolution of the split array beam-forming is improved by using the method of Hyper Beam-Forming(HBF) cross-spectrum. Under the condition of a certain signal-to-noise ratio, HBF cross-spectrum beam-forming method based on split array can effectively improve main lob width, reduce side-lobe effect and improve the resolution of direction finding significantly. Provide an effective judgment basis for the location estimation of acoustic beacons by using the intersection area of multi-point high-precision direction finding rays and the mean intersection. In this paper, the theoretical derivation process of the proposed method is given, and the error analysis of the azimuth estimation is carried out. The simulation and experimental results show that the side-lobe can be obviously suppressed by the split array HBF cross-spectrum method, and the accuracy and reliability of the target DOA estimation can be improved. The fusion method of the intersection area of multi-ray and the intersection point of multi-ray mean can effectively reduce the acoustic beacon search radius and improve search efficiency. © 2020 IEEE.

关键词： Signal to noise ratio

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Echo signal simulation system 3

Echo signal simulation system

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3rd International Conference on Mechanical, Electric and Industrial Engineering, MEIE 2020

作者： Gao, Feng Zhang, Yang Wang, Zhenshan Li, Guijuan Science and Technology on Underwater Test and Control Laboratory Dalian China

In order to meet the demand of realistic simulation for complex target echo signal in water, the indirect method of frequency domain is employed to simulate the target echo signal in this paper. The plate element method is first used to forecast complex target echo characteristics in typical water. After generating frequency response function data, the data is imported into the echo signal simulation system. The system adopts FPGA real-time signal processing system based on PXIe bus. It receives hydrophone output signal by A/D sampling, extracts the incident acoustic signal and makes frequency domain transformation. After multiplying the transformed signal and frequency response function, scattering echo spectrum is obtained. And then the time domain transformation is made to get the time series of the echo signal. The series is loaded into the transmitting transducer by the power amplifier and the echo signal is simulated. The system has the high fidelity of the model, stable and reliable hardware system, and software system for easy operation. © 2020 Published under licence by IOP Publishing Ltd.

关键词： Power amplifiers

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Study on the characteristics of dolphins click signal 5

Study on the characteristics of dolphins click signal

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5th International Conference on Communication, Image and Signal Processing, CCISP 2020

作者： Zhaohui, Zhang Yuan, Peng Science and Technology on Underwater Test and Control Laboratory Dalian China

ISBN: (纸本)9781728185897

Dolphins have a strong ability of target identification in the ocean, how to use it has become a new field of *** is mainly divided into three categories in the research of dolphin communication signals namely whistle, click and emergency signals. Dolphin Click sound is mainly used for target detection and recognition. In this paper, the research group designed a pool experiment to obtain the click signal when dolphin identify rubber bar, reef, aluminum bar and steel ball, and analyzes the signal form, frequency, spectrum change rule and other information from the perspective of time domain and time-frequency domain. The number of sine waves in click signal is analyzed when dolphins identify four kind of targets. We summarize six kinds of spectrum forms to classify the acquired acoustic signals, the probability of each spectrum form is analyzed and counted when dolphins detect and identify different *** results show that the click signal emitted by dolphins in target recognition is mainly one waveform click signal. The main energy of the frequency is concentrated at 0-200khz. © 2020 IEEE.

关键词： Signal processing

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Low-radioactivity ultrasonic hydrophone used in positioning system for Jiangmen Underground Neutrino Observatory

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Nuclear science and Techniques 2022年第6期33卷 102-113页

作者： Duo Teng Jiang-Lai Liu Guo-Lei Zhu Yue Meng Yuan-yuan Zhang Tao Zhang Kai Luo Rui Li Jia-Qi Hui School of Marine Science and Technology Northwestern Polytechnical UniversityXi’an 710072China National Key Laboratory for Underwater Information Processing and Control Northwestern Polytechnical UniversityXi’an 710072China School of Physics and Astronomy Shanghai Jiao Tong UniversityShanghai 200240China Tsung-Dao Lee Institute Shanghai Jiao Tong UniversityShanghai 200240China

To satisfy the accurate positioning requirement of the calibration source in the Jiangmen Underground Neutrino Observatory, a Tonpilz-type hydrophone with low radioactivity and high electroacoustics is *** radioactivity of the proposed hydrophone is strictly controlled by selecting pure raw materials, especially active piezoelectric ceramics. The electroacoustic performance of the hydrophone is improved by making structural optimization. High sensitivity and aimed directivity are achieved using 33-mode piezoelectric ceramic rings arranged in series and improvement in the radiating head of the Tonpilz hydrophone, respectively. All electroacoustic performances are studied through finite element *** simulations indicate that the electroacoustic performances of the hydrophones in linear alkylbenzene-based liquid scintillator can be approximately predicted according to the results in water because their differences caused by two types of acoustic media, water and liquid scintillator, are known. The tests show that the hydrophone prototype can achieve a maximum sensitivity of-209.3dB and a beamwidth of 132.2° at a frequency of 143 *** addition, eight hydrophones only contributed to a background radioactivity level of 26 ± 4 mHz in the neutrino analysis.

关键词： JUNO Liquid scintillator Tonpilz hydrophone Low radioactivity Sensitivity Directivity Finite element

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underwater Transducer Simulation Software Based on Finite Element Method

Underwater Transducer Simulation Software Based on Finite El...

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作者： Junwei Wang Zhong Luo Duo Teng Guolei Zhu School of Marine Science and Technology National Key Laboratory for Underwater Information Processing and Control Northwestern Polytechnical University Xi'an China

To remove the limitation of the special technical threshold in simulating or designing the transducer, an underwater transducer simulation software (UTS) is developed. UTS utilizes the interactive operation and the parametric design to achieve the automatic solution of the transducer. The finite element technology is the essences of UTS. In this study, the ANSYS processes are encapsulated by the ANSYS Parametric Design Language (APDL) macro and the JAVA language to achieve the electroacoustic simulations of a Tonpilz transducer. The results indicate that UTS is qualified in the transducer simulations.

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A Fast Design Method for Ultra Broadband Absorbers Using RC Equivalent Circuit Model

A Fast Design Method for Ultra Broadband Absorbers Using RC ...

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2022 International Applied Computational Electromagnetics Society Symposium, ACES-China 2022

作者： Kong, Xianglin Zhao, Lei Wang, Fengjun Zhang, Shengjun Fu, Yixiang Pang, Xiaoyu Liu, Xiaochun Shen, Xiaopeng China University of Mining and Technology School of Information and Control Engineering XuZhou China National Key Laboratory of Science and Technology on Test Physics & Numerical Mathematical Beijing China Key Laboratory of Aeronautical Science and Technology for High Performance Electromagnetic Window Jinan China China University of Mining and Technology School of Materials and Physics Xuzhou China

ISBN: (纸本)9781665452366

An accuracy and efficient approach is proposed to fast design ultra-wideband microwave absorbers. The RC equivalent circuit model of absorbers is established according to impedance matching and transmission line theory. The model is suitable for low and high-frequency absorbers composed of multilayer square high impendence surface (HIS) and air layers of impendence matching. Absorbers with different parameters can be fast designed by utilizing the proposed model and genetic algorithm. The reflection coefficient of RC circuit and full-simulation are in good agreement, both of them are lower than -10 dB within 2-18 GHz or 4-50 GHz (fractional bandwidth of 160% or 170.37%), with the total thickness close to the Rozanov limit. An absorber is fabricated and measured to further verify the accuracy of the model. The measured results have a good agreement with the RC circuit model, which indicates the proposed method is an efficient way for fast designing ultra-broadband thin absorbers using double-layer (or multilayer) square HIS. © 2022 IEEE.

关键词： Multilayers

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Comparison of Class I Flextensional Transducers with Concave Staves Machined by Different Materials

Comparison of Class I Flextensional Transducers with Concave...

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作者： Duo Teng Junwei Wang Zhong Luo Guolei Zhu School of Marine Science and Technology National Key Laboratory for Underwater Information Processing and Control Northwestern Polytechnical University Xi’an China

A Class I concave stave flextensional transducer is developed. Aiming at the electroacoustic performance of low frequency, high power, light weight and small size, the effect of the concave staves machined by the different materials on the flextensional transducer is studied. The finite element simulations illustrate the effect of the aluminium alloy, TC4 titanium alloy and 304 steel concave staves. The prototypes of the Class I concave stave flextensional transducer have been designed and fabricated. They have the size of Φ 96 × 160 mm, the weight of below 3 kg. Moreover, their resonance frequency is below 1.6 kHz and their source level is more than 194 dB. The tests verified the changes caused by the concave staves with different materials.

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