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Fine Sand and Clay Sediment acoustic Properties of the Novel Sediment Sample from the Arabian Sea:Experimental Investigations and Biot−Stoll Model Validation

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China Ocean engineering 2024年第1期38卷 169-180页

作者： Shahabuddin SHAIKH HUANG Yi-wang ZHANG Ze-chuan Habib Hussain ZUBERI National Key Laboratory of underwater acoustic Technology and College of Underwater Acoustic Engineering Harbin Engineering UniversityHarbin 150001China

The present study explores the physical and acoustic characteristics of fine sand and clay in novel seabed marine sediments from of Pakistan coastline of the Arabian Sea.The measured physical parameters included mean grain size,mass density,bulk density,salinity,porosity,permeability,pore size and mineralogical composition.acoustic properties,including sound speed and attenuation,in the high frequency range of 90-170 kHz were analyzed.A controlled laboratory setup with the acoustic transmission method and Fourier transform techniques was utilized to examine the sound propagation and absorption of novel seabed sediments.The standard deviation of mean sound speed in fresh water was 0.75 m/s,and attenuation was observed in the range of 0.43 to 0.61 dB/m.The mean sound velocity in sand and clay varied from 1706 to 1709 m/s and 1602 to 1608 m/s,respectively.Corresponding average attenuation was observed at 80 to 93 dB/m in sandy sediments and from 31.8 to 38.6 dB/m in clayey sediments.Sound velocity variation within sandy sediment is low,consistent with expected results,and smaller than the predicted uncertainty.However,clay sediment exhibited a positive linear correlation and low sound speed variation.Attenuation increased linearly with frequency for both sediments.Finally,the laboratory results were validated by using the Biot−Stoll model.The dispersion of sound speed in sandy and clayey sediments was consistent with the predictions of the Biot−Stoll model.Measured attenuation aligned more with Biot−Stoll model predictions due to improved permeability,tortuosity and pore size parameter fitting.

关键词： physical and acoustic characteristics marine sediments sound speed attenuation Biot−Stoll model

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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）.

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Three-dimensional parabolic equation model for seismo-acoustic propagation: Theoretical development and preliminary numerical implementation

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Chinese Physics B 2017年第11期26卷 269-278页

作者：唐骏朴胜春张海刚 acoustic Science and Technology Laboratory Harbin Engineering University College of Underwater Acoustic Engineering Harbin Engineering University

A three-dimensional（3D） parabolic equation（PE） model for sound propagation in a seismo-acoustic waveguide is developed in Cartesian coordinates, with x, y, and z representing the marching direction, the longitudinal direction, and the depth direction, respectively. Two sets of 3D PEs for horizontally homogenous media are derived by rewriting the 3D elastic motion equations and simultaneously choosing proper dependent variables. The numerical scheme is for now restricted to the y-independent bathymetry. Accuracy of the numerical scheme is validated, and its azimuthal limitation is analyzed. In addition, effects of horizontal refraction in a wedge-shaped waveguide and another waveguide with a polyline bottom are illustrated. Great efforts should be made in future to provide this model with the ability to handle arbitrarily irregular fluid-elastic interfaces.

关键词： three-dimensional parabolic equation sound propagation seismo-acoustic waveguides

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Observability Analysis in Parameters Estimation of an Uncooperative Space Target

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Computer Modeling in engineering & Sciences 2020年第1期122卷 175-205页

作者： Xianghao Hou Gang Qiao acoustic Science and Technology Laboratory and College of Underwater Acoustic Engineering Harbin Engineering UniversityHarbin150001China

To study the parameter estimating effects of a free-floating tumbling space target,the extended Kalman filter(EKF)scheme is utilized with different high-nonlinear translational and rotational coupled kinematic&dynamic models on the LIDAR measurements.Applying the aforementioned models and measurements results in the situation where one single state can be estimated differently with varying accuracies since the EKFs based on different models have different observabilities.In the proposed EKFs,the traditional quaternions based kinematics and dynamics and the dual vector quaternions(DVQ)based kinematics and dynamics are used for the modeling of the relative motions between a chaser satellite and an uncooperative target.In the non-contact estimating scenarios,only highly nonlinear relative attitude and range measurements:the grapple fixture on the target measured from the chaser satellite via vision-based sensors,can be used.By evaluating the results of the EKFs,the observability properties of each EKF are studied analytically and numerically with the the Observability Gramian matrices(OG)and the standard deviations for every estimated parameters.The analysis of observability perform intensive studies and reveal the intrinsic factors that affect the accuracy and stability of the parameters estimation of an uncooperative space target.Finally,the analytical and numerical results show the optimal composition of the kinematic&dynamic models and measurements.

关键词： Parameter estimations observability analysis dual quaternions extended Kalman filter

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Developments of parabolic equation method in the period of 2000–2016

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Chinese Physics B 2016年第12期25卷 106-117页

作者：徐传秀唐骏朴胜春刘佳琪张士钊 acoustic Science and Technology Laboratory Harbin Engineering University College of Underwater Acoustic Engineering Harbin Engineering University

Parabolic equation （PE） method is an efficient tool for modelling underwater sound propagation, particularly for problems involving range dependence. Since the PE method was first introduced into the field of underwater acoustics, it has been about 40 years, during which contributions to extending its capability has been continuously made. The most recent review paper surveyed the contributions made before 1999. In the period of 2000-2016, the development of PE method basically focuses on seismo-acoustic problems, three-dimensional problems, and realistic applications. In this paper, a review covering the contribution from 2000 to 2016 is given, and what should be done in future work is also discussed.

关键词： parabolic equation method underwater sound propagation seismo-acoustic transmission charac-teristics modelling three-dimensional problems

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Space-division multiple access for CDMA multiuser underwater acoustic communications

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Journal of Systems engineering and Electronics 2015年第6期26卷 1184-1190页

作者： Jingwei Yin Pengyu Du Guang Yang Huanling Zhou acoustic Science and Technology Laboratory Harbin Engineering University College of Underwater Acoustic Engineering Harbin Engineering University

Time reversal mirror （TRM） can use the physical characteristics of the underwater acoustic （UWA） channel to focus on the desired user in multi-user UWA communication. The active average sound intensity （AASI） detector can estimate all azimuths of users with the same frequency band at the same time in order to achieve directional communication by vector combination. Space-division multiple access （SDMA） based on TRM combined with the AASI detector is proposed in this paper, which can make the capacity of the code division multiple access （CDMA） UWA system significantly increase. The simulation and lake test results show that the 7-user UWA multi-user system can achieve low bit error communication.

关键词： underwater acoustic （UWA） communication space-division multiple access （SDMA） time reversal mirror （TRM） active average sound intensity （AASI） detector.

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一种基于迭代近端投影的被动声纳探测离网格DOA估计方法

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哈尔滨工程大学学报（英文版） 2024年第2期23卷 417-424页

作者：戴泽华张亮韩笑殷敬伟 National Key Laboratory of underwater acoustic Technology Harbin Engineering UniversityHarbin 150001China Key Laboratory for Polar acoustics and Application of Ministry of Education Harbin Engineering UniversityHarbin 150001China College of Underwater Acoustic Engineering Harbin Engineering UniversityHarbin 150001China

Traditional direction of arrival(DOA)estimation methods based on sparse reconstruction commonly use convex or smooth functions to approximate non-convex and non-smooth sparse representation problems.This approach often introduces errors into the sparse representation model,necessitating the development of improved DOA estimation algorithms.Moreover,conventional DOA estimation methods typically assume that the signal coincides with a predetermined grid.However,in reality,this assumption often does not hold true.The likelihood of a signal not aligning precisely with the predefined grid is high,resulting in potential grid mismatch issues for the algorithm.To address the challenges associated with grid mismatch and errors in sparse representation models,this article proposes a novel high-performance off-grid DOA estimation approach based on iterative proximal projection(IPP).In the proposed method,we employ an alternating optimization strategy to jointly estimate sparse signals and grid offset parameters.A proximal function optimization model is utilized to address non-convex and non-smooth sparse representation problems in DOA estimation.Subsequently,we leverage the smoothly clipped absolute deviation penalty(SCAD)function to compute the proximal operator for solving the model.Simulation and sea trial experiments have validated the superiority of the proposed method in terms of higher resolution and more accurate DOA estimation performance when compared to both traditional sparse reconstruction methods and advanced off-grid techniques.

关键词： DOA estimation Sparse reconstruction Off-grid model Iterative proximal projection Passive sonar detection

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基于聚焦变换解卷积的宽带稳健波束形成

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哈尔滨工程大学学报（英文版） 2024年第2期23卷 425-433页

作者：生雪莉陆典于洋蔡晨阳 National Key Laboratory of underwater acoustic Technology Harbin Engineering UniversityHarbin 150001China Key Laboratory for Polar acoustics and Application of Ministry of Education(Harbin engineering University) Ministry of EducationHarbin 150001China College of Underwater Acoustic Engineering Harbin Engineering UniversityHarbin 150001China

In the field of array signal processing,uniform linear arrays(ULAs)are widely used to detect/separate a weak target and estimate its direction of arrival from interference and noise.Conventional beamforming(CBF)is robust but restricted by a wide mainlobe and high sidelobe level.Covariance-matrix-inversed beamforming techniques,such as the minimum variance distortionless response and multiple signal classification,are sensitive to signal mismatch and data snapshots and exhibit high-resolution performance because of the narrow mainlobe and low sidelobe level.Therefore,compared with the wideband CBF,this study proposes a robust focused-and-deconvolved conventional beamforming(RFD-CBF),utilizing the Richardson–Lucy(R-L)iterative algorithm to deconvolve the focused conventional beam power of a half-wavelength spaced ULA.Then,the focused-and-deconvolved beam power achieves a narrower mainlobe and lower sidelobe level while retaining the robustness of wideband CBF.Moreover,compared with the wideband CBF,RFD-CBF can obtain a higher output signal-to-noise ratio(SNR).Finally,the performance of RFD-CBF is evaluated through numerical simulation and verified by sea trial data processing.

关键词： Wideband Beamforming Focusing transform Deconvolution High resolution Robust

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Sensitivity correction of co-vibrating vector hydrophone in standing wave tube by numerical calculation

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Chinese Journal of acoustics 2023年第4期42卷 464-478页

作者： ZHANG Hu CHEN Hongjuan ZHANG Honggang WANG Peng college of Ordnance engineering Naval University of EngineeringWuhan 430033 College of Underwater Acoustic Engineering Harbin Engineering UniversityHarbin 150001

When the sensitivity of a large-size vector hydrophone is calibrated in a standing wave tube, the distribution of the calibration sound field will be uneven, resulting in a large error in the calibration results. In the case that the accurate analytical expression of the calibration sound field cannot be obtained, the sound field simulation analysis model is established based on the actual standing wave tube calibration device. The sound pressure and acceleration values of vector hydrophone and reference scalar hydrophone are obtained by numerical calculation,and the sensitivity correction factor is derived by combining the sensitivity calibration formula and the reference value. After using the correction factor, the maximum absolute error between the test results and the reference value of vector hydrophones with different sizes is reduced to less than 2.0 d B. The results show that the numerical calculation method can effectively reduce the sensitivity calibration error of large-size vector hydrophones caused by the non-uniform sound field and expand the test object of the vector hydrophone standing wave tube calibration device.

关键词： correction numerical wave

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Strong interference suppression for subspace judgment analysis

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Chinese Journal of acoustics 2024年第1期43卷 49-63页

作者： SHENG Xueli LI Dewen CAO Ran YIN Jiarui ZHOU Xuan National Key Laboratory of underwater acoustic Technology Harbin Engineering UniversityHarbin 150001 College of Underwater Acoustic Engineering Harbin Engineering UniversityHarbin 150001 Qingdao Innovation and Development Base Harbin Engineering UniversityQingdao 266000

When strong interferences are present in underwater environments, the performance of target of interest(TOI) bearing estimation algorithms can be significantly degraded. To address this problem, an interference suppression method for subspace judgment(SSJ) is proposed, which aims to achieve TOI-bearing estimation in the presence of multiple strong interferences. With prior knowledge of the TOI bearing interval, the proposed method builds a judgment item using the correlation between the TOI-interferencenoise subspace and steering vector. The eigenvectors that are not dominated by the TOI are accurately identified via comparison with the estimated judgment threshold. And the identified eigenvectors will be subtracted from the sample covariance matrix(SCM) for interference suppression. The proposed method can obtain a residual SCM that primarily contains the signal of the TOI. It reduces the output power of interference and acquires TOI with a higher signal-to-interference plus noise ratio(SINR), which provides methodical support for improving the capability of TOI-bearing resolution. Simulation and experimental data processing results demonstrate that the proposed method effectively suppresses strong interferences outside TOI-bearing intervals. It reduces the output power of interference and sidelobe levels while improving the capability of TOI-bearing resolution. Compared with other interference suppression methods with subspace, the proposed method has a more robust interference suppression capability.

关键词： interferences estimation Strong

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