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作者： Gao Feng Key Laboratory for Underwater Test and Control Technology

A fractional order chaos system is first designed. It is a linear-nonlinear hybrid using fractional order logistic map. The fractional order chaos system is closer to the real nature phenomena and has better cryptography features than the integer order chaotic systems in dynamics, such as larger range of key space and almost no periodic windows in bifurcation diagrams. Then, we propose an image encryption scheme employing the superior chaotic features of the fractional order chaos system. Which chaotic sequences generated are used for permutation and addition/subtraction operation of encryption depends on the plaintext image. Security analysis and test results indicate that our encryption scheme has a high efficiency and superior security.

关键词： image Image Encryption Using Fractional Order Linear-Nonlinear Chaos

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Numerical computation on the scattering sound field distribution of rigid sphere in shallow water waveguide

Numerical computation on the scattering sound field distribu...

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作者： Wang Jihui Li Guijuan Jia Bing Wang Zhenshan Wang Rui Science and Technology on Underwater Test and Control Laboratory

Numerical computational model about the scattering fields of rigid sphere in shallow water waveguide is accomplished using boundary element method and normal mode model.A kind of modified CHIEF boundary element method is used to solve the non-uniqueness problem at characteristic frequency for exterior sound field *** green function for shallow water waveguide acoustic wave propagation is modified based on the normal mode *** acoustic pressure in the far field yields Kirchhoff Helmholtz equation and the scattering sound field distribution of rigid sphere in a Pekeris waveguide is *** the scattering sound field distribution of rigid sphere in the free field is *** results indicate that the waveguide influences the sound propagation,and it need to pay attention during the test.

关键词： Numerical computation on the scattering sound field distribution of rigid sphere in shallow water waveguide

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STF-GCN: A Multi-Domain Graph Convolution Network Method for Automatic Modulation Recognition via Adaptive Correlation

arXiv

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arXiv 2025年

作者： Shao, Mingyuan Fu, Zhengqiu Li, Dingzhao Zhang, Fuqing Cai, Yilin Hong, Shaohua Cao, Lin Peng, Yuan Qi, Jie School of Electronic Science and Engineering Xiamen University Fujian Xiamen361005 China School of Informatics Xiamen University Fujian Xiamen361005 China The Key Laboratory of Southeast Coast Marine Information Intelligent Perception and Application Ministry of Natural Resources Xiamen361005 China Science and Technology on Underwater Test and Control Laboratory Liaoning Dalian116013 China

Automatic Modulation Recognition (AMR) is an essential part of Intelligent Transportation System (ITS) dynamic spectrum allocation. However, current deep learning-based AMR (DL-AMR) methods are challenged to extract discriminative and robust features at low signal-to-noise ratios (SNRs), where the representation of modulation symbols is highly interfered by noise. Furthermore, current research on GNN methods for AMR tasks generally suffers from issues related to graph structure construction and computational complexity. In this paper, we propose a Spatial-Temporal-Frequency Graph Convolution Network (STF-GCN) framework, with the temporal domain as the anchor point, to fuse spatial and frequency domain features embedded in the graph structure nodes. On this basis, an adaptive correlation-based adjacency matrix construction method is proposed, which significantly enhances the graph structure’s capacity to aggregate local information into individual nodes. In addition, a PoolGAT layer is proposed to coarsen and compress the global key features of the graph, significantly reducing the computational complexity. The results of the experiments confirm that STF-GCN is able to achieve recognition performance far beyond the state-of-the-art DL-AMR algorithms, with overall accuracies of 64.35%, 66.04% and 70.95% on the RML2016.10a, RML2016.10b and RML22 datasets, respectively. Furthermore, the average recognition accuracies under low SNR conditions from -14dB to 0dB outperform the state-of-the-art (SOTA) models by 1.20%, 1.95% and 1.83%, respectively. © 2025, CC BY.

关键词： Frequency domain analysis

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Numerical simulation, verification and experiment validation on hydrodynamic performance and radiated noise properties of skewed propeller

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Journal of Physics: Conference Series 2020年第1期1633卷

作者： Fuqiang Ma Yansen Liu Lin Mu Bing Jia Scientific and Technology on Underwater Test and Control Laboratory Dalian China

Numerical simulation of hydrodynamic performance and radiated noise properties of the standard propeller is carried out by computational fluid dynamics (CFD) approach and acoustic analogy equation, and verifying and validating the numerical result by experiments in cavitation tunnel. Taking Potsdam Propeller test Case (PPTC) propeller as an example, the geometric model, grid model and numerical simulation boundary conditions are established. The comparison between numerical calculation and experimental results of open water characteristics of propeller, including thrust coefficient, torque coefficient and efficiency shows that the numerical model is reliable. Under the condition of good agreement between numerical simulation and experimental results of unsteady hydrodynamic characteristics, which contains the pressure distribution of blades, cavitation properties, the wake vortex distribution of the propeller, the numerical calculation and characteristic analysis of propeller radiated noise are carried out. The results show that the relation between the radiated noise of the propeller and the inherent structure and the motion state is correlated. The research can provide a theoretical basis for the target detection and recognition based on such characteristics.

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An auditory periphery model for improving narrow-band noise recognition rate of underwater targets

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Chinese Journal of Acoustics 2018年第3期37卷 325-340页

作者： LIN Zhengqing QIU Mengran BA Wei Science and Technology on Underwater Test and Control Laboratory

The recognition rate of the auditory periphery features decreases when the model is used to identify underwater targets in practice. To solve this problem, an improved method based on Gammatone filter bank is proposed. Firstly, after the reason of the decreasing of the recognition results is analyzed, the mechanism of multichannel data acquisition in acoustic engineering may narrow down signal frequency range, which leads to time-frequency features distortion. Secondly, the Gammatone filter bank is implemented to simulate frequency decom- position characteristics of human ear basilar membrane. Since the class information of the underwater noise signal is mostly contained in low frequency range, the auditory features of the conventional model are interpolated and the channel number of the filter bank and the central frequency of each frequency band are adjusted accordingly to obtain a 27-dimensional feature vector of the narrow-band target signal. The adjusted model may reflect the target＇s time- frequency feature more precisely. Finally, the performance of the auditory features is tested by a Neural Network classifier. The experiment results show that the modified auditory model is more effective than the conventional ones. The major information contained in broadband signals is reserved and the classification ability for real targets is further enhanced. The recog- nition results are increased from 82.59% to 88.80%. The modified auditory features effectively improve the recognition rate for underwater target radiated noise signals.

关键词： An auditory periphery model for improving narrow-band noise recognition rate of underwater targets

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Simulation of Phase Characteristics of underwater Target Acoustic Scattering

Simulation of Phase Characteristics of Underwater Target Aco...

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Signal, Information and Data Processing (ICSIDP), IEEE International Conference on

作者： JinTao Yong YunFei Chen Bing Jia Yang Zhang Science and Technology on Underwater Test and Control Laboratory Dalian China

ISBN: (数字)9781728123455

ISBN: (纸本)9781728123462

Acoustic scattering phase of underwater target is one of the key scattering characteristics, which can be used as an extra parameter for target detection and an identifier for target identification. On the basis of analyzing and processing the simulation data of benchmark scaled model, the phase characteristics of acoustic scattering signals associated with the attribute information of underwater target are proposed and researched. The law of the phase characteristics with frequency and target azimuth are obtained. It shows that the research on the phase of target acoustic scattering can increase the amount of information which can be utilized in target detection and recognition. The results demonstrate that the target phase characteristics will be important for the acquisition of increased levels of information, critical for the development of automated targets detection and species identification.

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Design of Ship Radiated Noise Signal Generator Based on FPGA

Design of Ship Radiated Noise Signal Generator Based on FPGA

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Signal, Information and Data Processing (ICSIDP), IEEE International Conference on

作者： Hu Chen Zhang Fengzhen Li Guijuan Zhang Zhaohui Mu Lin Hu Wenshuai Science and Technology on Underwater Test and Control Laboratory Dalian China

ISBN: (数字)9781728123455

ISBN: (纸本)9781728123462

The rapid development of FPGA provides a new platform for target signal simulation. Firstly, the components of ship radiated noise are analyzed in the paper. Then a module of ship radiated noise signal generator based on FPGA is designed, generating 20Hz-10kHz frequency band noise to simulate ship radiated noise. Finally, two kinds of signal are used to test the generator module, and the performance is in line with expectations. The generating module can be used as a sound source in noise experiment and can also simulate underwater targets.

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Numerical analysis on target strength of the air filled cylindrical elastic shell 1

Numerical analysis on target strength of the air filled cyli...

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1st International Conference on Advanced Algorithms and control Engineering, ICAACE 2018

作者： Wang, Jihui Li, Guijuan Jia, Bing Wang, Zhenshan Wang, Rui Science and Technology on Underwater Test Control Laboratory Dalian China

Aimed at simulating the air filled finite cylindrical shell target strength, the numerical calculation method of scattering form function and target strength is given in this paper using the theory of Stanton T K. Cylindrical shells of different material properties, thickness, length are calculated, and the results indicate that factor of the material property and dimension is very important. Compared with other kinds of material properties, the gum rubber cylindrical shell has much more greater target strength for low frequency. Factors of radius and thickness have big effect to its fundamental resonance and the choice should be made in accordance with the actual needs. The numerical study provides theoretical basis and design reference for engineering application. © Published under licence by IOP Publishing Ltd.

关键词： Numerical methods

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Numerical computation on the scattering sound field distribution of rigid sphere in shallow water waveguide

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IOP Conference Series: Materials Science and Engineering 2020年第3期780卷

作者： Wang Jihui Li Guijuan Jia Bing Wang Zhenshan Wang Rui Science and Technology on Underwater Test and Control Laboratory Dalian China

Numerical computational model about the scattering fields of rigid sphere in shallow water waveguide is accomplished using boundary element method and normal mode model. A kind of modified CHIEF boundary element method is used to solve the non-uniqueness problem at characteristic frequency for exterior sound field computation. The green function for shallow water waveguide acoustic wave propagation is modified based on the normal mode model. The acoustic pressure in the far field yields Kirchhoff Helmholtz equation and the scattering sound field distribution of rigid sphere in a Pekeris waveguide is achieved. Also the scattering sound field distribution of rigid sphere in the free field is calculated. The results indicate that the waveguide influences the sound propagation, and it need to pay attention during the test.

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Research on the Method of Judging the Transfer Path of Warship Transient Noise Excitation Source based on Information Similarity

Research on the Method of Judging the Transfer Path of Warsh...

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IEEE International Conference on Power, Intelligent Computing and Systems (ICPICS)

作者： Zhenyu Li Bo Zhang Xuefeng Dai Yanqiong Liu First Laboratory Dalian Scientific Test and Control Technology Institute Dalian China

The warship is a very complicated system with many equipments and many excitation sources which can produce transient noise. Transient noise is mainly transmitted to the hull through elastic installation, pedestal and other supporting structures and non-supporting structures such as pipelines and cables. The vibration energy passes through the hull to the acoustic field and forms the radiated noise. Therefore, how to quickly and effectively find out the excitation source of ship transient noise has important military significance. It is difficult to distinguish the transmission channel of the excitation source of the transient noise because of the variety of ways of generating the transient noise and the interference of the mechanical noise. This makes the problem of excitation source discrimination become one of the important research directions of warship transient noise analysis. This paper aims to solve the problem of identifying the main transmission path of the excitation source. In this paper, through the study of principal component decomposition, instantaneous information similarity and so on, combined with the physical model of vibration transfer path, the main transfer path discrimination method suitable for the warship transient noise excitation source is established, and the validity of the method is verified by theoretical simulation.

关键词： Marine vehicles Transient analysis Vibrations Mathematical model Noise measurement Interference Steady-state

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