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Frequency domain polarization weighted ESPRIT method for bearing angle

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Journal of Systems Engineering and Electronics 2014年第5期25卷 769-775页

作者： Wei Liu shengchun piao Junyuan Guo Qingxin Meng Hanhao Zhu Science and Technology on Underwater Acoustic Laboratory Harbin Engineering University College of Underwater Acoustic Engineering Harbin Engineering University

The signal to noise ratio （SNR） of seismic waves is usually very low after long distance transmission. For this condition, to improve the bearing estimation capability in the low SNR, a frequency domain polarization weighted ESPRIT method using a single vector device is proposed. The frequency domain polari- zation parameters extracted from the signals are used to design the weighted function which is applied to the received signals. The bearing angle and the target frequency are estimated through ESPRIT using the weighted signals. The simulation and experiment results show that the presented method can obtain accurate estimation values under the low SNR with little prior information.

关键词： vector seismic signal frequency domain polarizationweight bearing angle estimation estimation of signal parametersvia rotational invariance techniques （ESPRIT）.

Analysis of horizontal migration characteristics of convergence zone and its critical frequency

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Chinese Journal of Acoustics 2022年第4期41卷 329-344页

作者： ZHANG Haigang MA Zhikang FU Jinshan piao shengchun Acoustic Science and Technology Laboratory Habrbin Engineering UniversiyHarbin 150001 Key Laboratory of Marine Information Acquistion and Security(Habrbin Engineering Universiy) Ministry of Industryand Information TechnologyHarbin 150001 College of Underwater Acoustic Engeering Habrbin Engineering UniversiyHarbin 150001

The horizontal migration characteristics of convergence zone in complete sound fixing and ranging channel are studied by simulation model.The critical frequency of this phenomenon is derived according to Snell’s law and Lloyd’s mirror effect.It is found that when sound frequency is lower than critical frequency,the dominant mode of the convergence zone is frequency dependent.With the decrease of frequency,the convergence zone moves horizontally towards sound source,and the transmission loss increases significantly.When sound frequency is higher than the critical frequency,the dominant mode of convergence zone is almost frequency independent and the position and transmission loss of convergence zone will not change significantly with frequency.Most notably,the critical frequency varies with source depth.Critical frequency can be used to determine the frequency condition that need to be satisfied when convergence zone horizontally migrates at a specific source depth.The critical frequency formula contains source depth information which provides a good avenue for shallow target depth estimation in deep ocean.

关键词： effect. convergence critical

Perfectly Matched Layer for an Elastic Parabolic Equation Model in Ocean Acoustics

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Journal of Ocean University of China 2017年第1期16卷 57-64页

作者： XU Chuanxiu ZHANG Haigang piao shengchun YANG Shi’e SUN Sipeng TANG Jun Acoustic Science and Technology Laboratory Harbin Engineering UniversityHarbin 150001P.R.China College of Underwater Acoustic Engineering Harbin Engineering UniversityHarbin 150001P.R.China

The perfectly matched layer(PML) is an effective technique for truncating unbounded domains with minimal spurious reflections. A fluid parabolic equation(PE) model applying PML technique was previously used to analyze the sound propagation problem in a range-dependent waveguide(Lu and Zhu, 2007). However, Lu and Zhu only considered a standard fluid PE to demonstrate the capability of the PML and did not take improved one-way models into consideration. They applied a [1/1] Padé approximant to the parabolic equation. The higher-order PEs are more accurate than standard ones when a very large angle propagation is considered. As for range-dependent problems, the techniques to handle the vertical interface between adjacent regions are mainly energy conserving and single-scattering. In this paper, the PML technique is generalized to the higher order elastic PE, as is to the higher order fluid PE. The correction of energy conserving is used in range-dependent waveguides. Simulation is made in both acoustic cases and seismo-acoustic cases. Range-independent and range-dependent waveguides are both adopted to test the accuracy and efficiency of this method. The numerical results illustrate that a PML is much more effective than an artificial absorbing layer(ABL) both in acoustic and seismo-acoustic sound propagation modeling.

关键词： elastic parabolic equation perfectly matched layer artificial absorbing layer

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小尺寸声矢量平面阵三维波束形成方法

声学学报 2023年第3期48卷 471-481页

作者：李良文朴胜春郭俊媛叶扬哈尔滨工程大学水声技术全国重点实验室哈尔滨150001 工业和信息化部海洋信息获取与安全工信部重点实验室(哈尔滨工程大学) 哈尔滨150001 哈尔滨工程大学水声工程学院哈尔滨150001

提出了一种基于声场多极子展开的小尺寸声矢量平面阵三维波束形成方法。该方法利用了声场的垂直振速信息,并结合球谐波函数与多极子模态之间的联系,可用二维的阵列结构合成指向任意方向的三维波束图,简化了三维波束形成所需的阵列结构。... 详细信息

提出了一种基于声场多极子展开的小尺寸声矢量平面阵三维波束形成方法。该方法利用了声场的垂直振速信息,并结合球谐波函数与多极子模态之间的联系,可用二维的阵列结构合成指向任意方向的三维波束图,简化了三维波束形成所需的阵列结构。以3×3均匀矩形阵为例的仿真结果表明,在相邻阵元间距小于0.2倍信号波长时,所提方法引入的差分近似误差可被忽略,所得阵列波束图接近理论波束图。相比于声压球面阵三维波束形成方法,所提方法在低频段能在获得相同阵增益的同时有着更好的稳健性,为实现小尺寸阵列的三维波束形成提供了一种可靠的方法。

关键词：小尺寸平面阵三维波束形成矢量传感器多极子展开

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运动目标时空频信号变换与多维信息关联

声学学报 2023年第5期48卷 920-936页

作者：石蕴佳朴胜春郭俊媛张柳哈尔滨工程大学水声技术全国重点实验室哈尔滨150001 工业和信息化部海洋信息获取与安全工信部重点实验室(哈尔滨工程大学) 哈尔滨150001 哈尔滨工程大学水声工程学院哈尔滨150001

提出了一种针对水中匀速直线运动目标的时空频信号变换方法。首先对接收信号作时频分析和频域波束形成,根据选定的目标航向对频率-方位-时间三维信号空间中的接收信号进行由基阵坐标系到目标坐标系的视在方位变换,使目标线谱信号由三维... 详细信息

提出了一种针对水中匀速直线运动目标的时空频信号变换方法。首先对接收信号作时频分析和频域波束形成,根据选定的目标航向对频率-方位-时间三维信号空间中的接收信号进行由基阵坐标系到目标坐标系的视在方位变换,使目标线谱信号由三维空间轨迹变换为变换域中对应平面切片上的二维轨迹,该切片由频率与方位信息联合构成的轴和时间轴构成。研究结果表明,该方法能够在变换后的信号空间中将目标线谱信号的三维轨迹转换为相应切片上的二维轨迹,相比三维信号空间更容易获得多维信息联合处理的信号处理增益。

关键词：运动目标坐标变换多维信息关联 Radon变换

An energy-conserving two-way coupled mode model for underwater acoustic propagation

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Chinese Journal of Acoustics 2016年第2期35卷 97-110页

作者： MO Yaxiao piao shengchun ZHANG Haigang LI Li Acoustic Science and Technology Laboratory Harbin Engineering University College of Underwater Acoustic Engineering Harbin Engineering University

In order to avoid the energy non-conservation in two-way sound field calculations, which results from certain approximation of non-horizontal boundary, an energy-conserving two- way coupled mode propagation model is developed. During the derivation of this model, the non-horizontal boundary condition is treated strictly instead of making an approximation. The coupling equations, which are easy to numerical implementation, are derived from the equation of motion and the equation of continuity. Moreover, the validity of this model is illustrated with several numerical examples of different bottom parameters and the equation of energy conservation. It is shown that a boundary correction is introduced by the strict formulizing of the boundary condition in this model. This boundary correction guarantees the coupling coefficients being symmetrical and makes the sound fields satisfy the energy conservation. Thus, the energy-conserving coupled model is able to handle non-horizontal boundaries adequately, and the two-way sound fields in a non-horizontal stratified media can be calculated exactly by this model.

关键词： mode

Waveguide invariant estimation in elastic Pekeris waveguide

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Chinese Journal of Acoustics 2017年第1期36卷 113-129页

作者： ZHU Hanhao piao shengchun ZHANG Haigang LIU Wei Institute of Marine Science and Technology Zhejiang Ocean University Zhoushan 316022 Acoustic Science and Technology Laboratory Harbin Engineering University Harbin 150001 College of Under eater Acoustic EngineeringHarbin Engineering University Harbin 150001

Focus on sound intensity, particle velocity, complex sound intensity and waveguide impedance, the formation mechanism of interference structures in range-frequency domain for the above four kinds of physical quantities in Pekeris waveguides is analyzed based on Nor- mal Mode Theory. Also, a sea-trial with broadband radiated source is conducted to verify the analysis results. Both the simulation results and the analysis of sea-trial data indicate that, in range-frequency domain, the four kinds of physical quantities will exhibit a stable interfer- ence structure which can be expressed with waveguide invariant /3. Among these quantities, the coherent components of complex sound intensity can better reflect the interference char- acteristics of the waveguide. Finally, a multi-scale linear filter is introduced to deal with the sea-trial LOFAR （Low Frequency Analysis Recording） spectrum, the processing results show that the proposed filter can effectively enhance the interference characteristics in images, and conductively detect and extract striations＇ information from interference structures in LOFAR spectrum.

关键词： Waveguide invariant estimation in elastic Pekeris waveguide

Broadband interference of received pulse for single normal mode and solitary internal wave localization

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Chinese Journal of Acoustics 2020年第2期39卷 151-163页

作者： piao shengchun ZHANG Shizhao LIU Jiaqi LI Xiaoman IQBAL Kashif Acoustic Science and Technology Laboratory Harbin Engineering University Harbin 150001 Key Laboratory of Marine Information Acquisition and Security Harbin Engineering UniversityMinistry of Industry and Information Technology Harbin 150001 College of Underwater Acoustic Engineering Harbin Engineering University Harbin 150001

To analyze the solitary internal wave(SIW) influence on acoustic field interference pattern and thereby monitor SIW, for broadband pulse signal propagating through SIWs, we adopt a parabolic equation model, and simulate the variation of received single normal mode(SNM) pulse sequence with SIW position, and analyze the spatiotemporal interference characteristics and mechanism of the sequence. Based on the coupled mode theory, we derive the relationship between SIW position and interference striation slope(ISS). The relationship can monitor the SIW position precisely, with greatly improved precision and robustness compared with previous work. Furthermore, based on the SNM interference pattern periodicity in frequency, we also develop another method to estimate SIW range, with better real-time property than the first method. The SIW-normal mode interference relationship can be used for improving acoustic field localization in the presence of SIWs, which has great value for oceanology,marine engineering, marine military and so on. Besides, the relationship can be expanded to other detection for local variation, e.g., detecting metal flaw and locating dramatic variation in seabed topography.

关键词： pulse mode wave

Method of coupled mode for long-range bottom reverberation

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Science China(Physics,Mechanics & Astronomy) 2010年第12期53卷 2216-2222页

作者： GAO Bo , YANG ShiE, piao shengchun & HUANG YiWang National Laboratory of Underwater Acoustic Technology,Harbin Engineering University, Harbin 150001, China National Laboratory of Underwater Acoustic Technology Harbin Engineering University Harbin China

The theory of coupled mode is used for modeling the long-range bottom reverberation in shallow water caused by bottom roughness. The distant bottom reverberation level and spatial coherence of impulsive source are both derived. The results agree with those from the classical reverberation model, and are compared with the experimental data. The influence of source bandwidth and the distance between sources and receivers on the intensity of bottom reverberation are particularly discussed. The method is shown to be available for both the monoand the bi-static cases.

关键词： shallow water couple mode bottom reverberation