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A numerically stable coupled-mode formulation for acoustic propagation in range-dependent waveguides

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Science China(Physics,Mechanics & Astronomy) 2012年第4期55卷 572-588页

作者： LUO WenYu YANG ChunMei qin jixing ZHANG RenHe State Key Laboratory of Acoustics Institute of AcousticsChinese Academy of SciencesBeijing 100190China Graduate University of Chinese Academy of Sciences Beijing 100049China

In this paper,a stepwise coupled-mode model with the use of the direct global matrix approach is *** method is capable of handling two-dimensional problems with either a point source in cylindrical geometry or a line source in plane *** the use of the direct global matrix approach,this method is numerically *** addition,by introducing appropriately normalized range solutions,this model is free from the numerical overflow ***,we put forward source conditions appropriate for the line-source problem in plane *** a result,this method is capable of addressing the scenario with a line source on top of a sloping ***-form expressions for coupling matrices are derived and applied in this paper for handling problems with pressure-release boundaries and a homogeneous water *** numerical simulations indicate that the proposed model is accurate,efficient,and numerically ***,this model can serve as a benchmark model in range-dependent propagation *** this method is verified by an ideal wedge problem in this paper,the formulation applies to realistic problems as well.

关键词： coupled-mode theory range-dependent waveguide direct global matrix approach

Characterization and modeling of wind-dominated ambient noise in South China Sea

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Science China(Physics,Mechanics & Astronomy) 2017年第12期60卷 70-73页

作者： DongGe Jiang ZhengLin Li jixing qin ZhaoHui Peng Hao Shao State Key Laboratory of Acoustics Institute of Acoustics Chinese Academy of Sciences Beijing 100190 China University of Chinese Academy of Sciences Beijing 100190 China

The action of wind on the sea surface plays an important role in the noise generation *** surface wind speed can be estimated accurately provided there is an accurate understanding of the relationship between the ocean ambient noise and wind *** measurements and analyses of the wind dependence of ambient noise have been *** approximate empirical rule given by Wenz[1]states that in the frequency band between 0.5and 5 kHz,the ambient sea-noise spectrum levels decrease

关键词： ambient dominated ocean approximate meteorological empirical have deviation shallow Figure

Sound propagation from the shelfbreak to deep water

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Science China(Physics,Mechanics & Astronomy) 2014年第6期57卷 1031-1037页

作者： qin jixing ZHANG RenHe LUO WenYu PENG ZhaoHui LIU JianJun WANG DeJun State Key Laboratory of Acoustics Institute of AcousticsChinese Academy of Sciences Graduate University of Chinese Academy of Sciences

Motivated by a phenomenon in an experiment conducted in the Northwestern Pacific indicating that the energy of the received signal around the sound channel axis is much greater than that at shallower depths,we study sound propagation from the transitional area(shelfbreak)to deep *** simulations with different source depths are first performed,from which we reach the following *** the source is located near the sea surface,sound will be strongly attenuated by bottom losses in a range-independent oceanic environment,whereas it can propagate to a very long range because of the continental *** the source is mounted on the bottom in shallow water,acoustic energy will be trapped near the sound channel axis,and it converges more evidently than the case where the source is located near the sea ***,numerical simulations with different source ranges are *** comparing the relative energy level in the vertical direction between the numerical simulations and the experimental data,the range of the air-gun source can be approximated.

关键词： sound propagation transitional area deep water parabolic equation

Geoacoustic inversion in shallow water by matching the vertical-particle-velocity

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Chinese Journal of Acoustics 2023年第3期42卷 288-306页

作者： TAN Peng SUN Mei qin jixing YANG Desen Acoustic Science and Technology Laboratory Harbin Engineering UniversityHarbin 150001 Key Laboratory of Marine Information Acquisition and Security(Harbin Engineering University) Ministry of Industry and Information TechnologyHarbin 150001 College of Underwater Acoustic Engineering Harbin Engineering UniversityHarbin 150001 School of Physics and Electronic Engineering Taishan UniversityTaian 271000 State Key Laboratory of Acoustics Institute of AcousticsChinese Academy of SciencessBeijing 100190

Bottom acoustic parameters are vital for studying sound propagation properties and their applications in ocean *** propagation properties and normal-mode structure of vertical-particle-velocity in an ocean environment with a thermocline in shallow water were studied in the Yellow *** Results reveal that high energy of the verticalparticle-velocity exists at most depth except for near-bottom depth when the source and receiver are both below the ***,high-order modes contribute more to the verticalparticle-velocity and vertical-particle-velocity-based matched-field-processing(MFP)inversion method can be highly sensitive to bottom parameters compared to sound ***,the effects of the bottom absorption coefficient on the vertical-particle-velocity-based MFP inversion method are *** is shown that accurate sound velocity,density and water depth can be obtained only when the bottom absorption coefficient is set close to the real value during *** using the vertical-particle-velocity signals recorded by vector hydrophones during the experiment and determining the bottom sound velocity,bottom density and water depth under different bottom absorption coefficients,stable inversion results were *** transmission losses of the sound pressure at different ranges were used to invert the bottom absorption *** transmission losses of sound pressure calculated using the inverted bottom parameters are consistent with the experimental results obtained from the pressure hydrophones in the experiment.

关键词： shallow ocean particle

Effect of sound speed profile on the structure of long-range acoustic pulse

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Chinese Journal of Acoustics 2024年第1期43卷 64-81页

作者： WU Shuanglin qin jixing LI Zhenglin WU Yushen ZHANG Renhe State Key Laboratory of Acoustics Institute of AcousticsChinese Academy of SciencesBeijing 100190 University of Chinese Academy of Sciences Beijing 100049 School of Ocean Engineering and Technology Sun Yat-sen UniversityZhuhai 519000 Southern Marine Science and Engineering Guangdong Laboratory(Zhuhai) Zhuhai 519082

The time arrival structure of acoustic pulse signals propagating in ocean waveguides is of great significance for underwater acoustic communication and navigation. Using the deep-sea sound propagation data from the experiments respectively conducted in the East Indian Ocean(EIO) and the South China Sea(SCS) with explosion sources near the sound channel axis(SCA), long-range transmission loss(TL) and time arrival structure of acoustic pulses for different sound speed profiles(SSPs) are compared. In the EIO environment, sound energy transmitting along the SCA is relatively large, and the corresponding signals arrive first, whereas signals propagating away from the SCA arrive late. In the full receiving depth, it shows a branch structure where the waveform near the SCA arrives earlier than other depths, which is totally different with the characteristics of the sound pulse in the SCS. Combined with the parametric mathematical model of deep-sea sound channel, the influence mechanism of SSP on the time arrival structure of long-range pulse propagation is theoretically analyzed, which well explains the phenomenon observed in the two experiments.

关键词： depths Indian sound

Experimental analysis of acoustic propagation and source localization based on the underwater acoustic glider in Eastern Indian Ocean

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Chinese Journal of Acoustics 2022年第3期41卷 195-211页

作者： WU Yushen LI Zhenglin qin jixing WU Shuanglin WANG Guangxu State Key Laboratory of Acoustics Institute of AcousticsChinese Academy of Sciences Beijing 100190 College of Physical Science University of Chinese Academy of Sciences Beijing 100049

In order to acquire hydrologic and acoustic information at the same time,the underwater glider is used as a synchro observing platform and an algorithm of source localization estimation based on the glider in deep water is *** hydrologic and acoustic data acquired by the glider in the Eastern Indian Ocean are used to analyze the self-noise of the glider and the characteristics of acoustics signal *** underwater track of the glider is updated by using underwater dead *** to the time delay of the received signals,the underwater sound source localization estimation is *** results indicate that the self-noise of the glider is quite close to the ambient noise at the no-motor *** sound transmission losses(TLs)of experiment and simulation are in great *** estimation results of underwater sound source localization are consistent with measurement and the estimation error is less than 5%.The glider loaded with self-contained hydrophones can get hydrologic and acoustic information at the same time,which is important for the acoustic propagation analysis and target localization.

关键词： underwater estimation propagation

The convergence of sound field in a South China Sea canyon

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Chinese Journal of Acoustics 2020年第2期39卷 164-175页

作者： ZHANG qingqing LI Zhenglin qin jixing LI Wen WU Shuanglin State Key Laboratory of Acoustics Institute of AcousticsChinese Academy of Sciences Beijing 100190 University of Chinese Academy of Sciences Beijing 100049

The sound propagation characteristics in a canyon environment are analyzed using the data from the northern South China Sea. The experimental results show that the energy begins to bend to a deeper place with the depth change of the canyon and the sound transmission losses(TLs) reach the maximum near the center of the canyon due to the combined effect of the negative gradient sound speed profile and the seabed topography. As the sea become shallow gradually, the energy is concentrated due to the seabed reflection, thus the TLs reduce by over 20 d B compared with the TLs results got from the simple slope to the deep water environment. Moreover, when the convergence effects are less than the loss caused by diffusion,seabed reflection, etc. the TLs are minimized and then increase with an increase in *** the last segment, the gradual convergence of the energy is highlighted again, and the TLs decrease 10 d B when the water depth suddenly decreases from 850 m to 311 m within 8 ***, the convergence of sound field, which is caused by the topographic change in the canyon environment, is explained by the ray theory and the parabolic equation method.

关键词： seabed shallow topography

The characteristic of sound propagation in deep water and underwater source localization in the direct zone

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Chinese Journal of Acoustics 2019年第4期38卷 433-444页

作者： WANG Mengyuan LI Zhenglin WU Shuanglin qin jixing YU Yanxin State Key Laboratory of Acoustics Institute of AcousticsChinese Academy of SciencesBeijing 100190 University of Chinese Academy of Sciences Beijing 100049

The multiple-path sound propagation in deep water is conducive to source localization of an underwater *** transmission losses(TLs) and broadband pulse multiple-path propagation characteristics from a deep receiver is analyzed by using the experimental data from deep water area in the South China Sea(SCS).The results indicate that the width of the direct zone near the bottom of 4300 m water depth is about 30 *** TLs in the direct zone near the bottom are much less than those in the shadow *** is meaningful for underwater sound source ***,the time delay between the direct path and the bottomsurface-reflected path for a receiver near the bottom decreases monotonically with the source *** to the linear relationship between the time delay of multipath and source range,a source localization method is presented to estimate the range of underwater *** experimental results show that the estimated ranges are consistent with the global position system(GPS) measurements,and the mean square error of the estimation results is less than 0.28 km.

关键词： underwater propagation sound

Analysis and comparison between two coupled-mode methods for acoustic propagation in range-dependent waveguides

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Chinese Journal of Acoustics 2014年第1期33卷 1-21页

作者： qin jixing LUO Wenyu ZHANG Renhe YANG Chunmei State Key Laboratory of Acoustics Institute of Acoustics Chinese Academy of Sciences Beijing 100190 University of Chinese Academy of Sciences Beijing 100049

Two coupled-mode methods, namely DGMCM （Direct-Global-Matrix Coupled- Mode Method） and CCMM （Consistent Coupled-Mode Method）, are analyzed and compared. First, both of these two methods provide two-way solutions, and hence they are accurate models. Second, the series of local vertical modes in DGMCM converges as fast as that in CCMM, whereas DGMCM has a more tolerable requirement of the number of segments than CCMM. Third, these two models obtain the field solution by solving the coupled-mode system with different coefficient matrices, in which the computational effort for the required parameters is almost the same. Finally, DGMCM can handle some problems which are difficult for CCMM, such as in a waveguide with a rough bottom, a line source located right on top of a sloping bot- tom, or in the presence of multiple sources. In DGMCM, closed-form expressions for coupling matrices in a two-layer waveguide are given. In addition, the formulation for the line-source problem in plane geometry is derived to update CCMM.

关键词： mode Analysis and comparison between two coupled-mode methods for acoustic propagation in range-dependent waveguides