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Performance analysis of source ranging by use of virtual receiver technique under different frequency bands

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Chinese Journal of Acoustics 2015年第4期34卷 387-400页

作者： YAO Meijuan MA Li LU Licheng guo shengming Institute of Acoustics Chinese Academy of Sciences Key Laboratory of Underwater Acoustics Environment Chinese Academy of Sciences Chinese Academy of Sciences University

The traditional matched field processing localization need complicated computation to get the replica field and has high dependence on environment parameters and acoustic field model. To overcome the shortcoming, virtual receiver technique is used for source ranging. A virtual receiver is constructed by correlating the two signals of the guide source and the objective source received by a vertical line array. Then, the slope of the interference striation of the virtual field is estimated using relevant signal processing method. Combining with the waveguide invariant/3, the range of the objective source is determined. Through the numerical simulations and data processing collected from the experiment carried out in the South China Sea in 2004, the virtual receiver technique for broadband source ranging under the slope- bottom shallow water environment is discussed. As the frequency increases, the frequency bands should be broadened to obtain complete interference striation for good ranging results. In data processing, the receiving array spacing is too large to promise the orthogonality of the modes as the frequency increases and ranging results become worse.

关键词： Performance analysis of source ranging by use of virtual receiver technique under different frequency bands

Trans-dimensional Bayesian geoacoustic inversion in shallow water

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Chinese Journal of Acoustics 2023年第4期42卷 407-422页

作者： WU Weiwen REN Qunyan LU Licheng guo shengming MA Li Key Laboratory of Underwater Acoustic Environment Institute of AcousticsChinese Academy of SciencesBeijing 100190 University of Chinese Academy of Sciences Beijing 100049

To deal with the inversion problem when the spatial structure of seaffoor sediments is unknown, a trans-dimensional particle filter method is proposed, where the cross-spectral density of the pressure field is used to estimate the sediment layering structure and geoacoustic parameters. The simulation results show that the number of sediment layers and geoacoustic parameters can be effectively estimated using the proposed method, and the parallel particle calculation makes this method more efficient than reversible jump Monte Carlo Markov chain(rjMCMC) sampling. A linear frequency-modulated signal received by a vertical line array in the South China Sea is processed using the proposed trans-dimensional particle filter. The inversion results of the sediment layers and geoacoustic parameters are similar to those acquired by rjMCMC inversion. The number of sediment layers and the posterior probability density of parameters can be effectively estimated using this method.

关键词： shallow dimensional MCMC

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An improved underwater acoustic communication channel estimation based on the A*OMP algorithm

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Chinese Journal of Acoustics 2023年第1期42卷 58-70页

作者： LIU Biao JIA Ning HUANG Jianchun XIAO Dong JIA Yuqing guo shengming MA Li Institute of Acoustics Chinese Academy of SciencesBeijing100190 Key Laboratory of Underwater Acoustic Environment Chinese Academy of SciencesBeijing100190 University of Chinese Academy of Sciences Beijing100049

A*Orthogonal Matching Pursuit(A*OMP)was modified and applied to underwater acoustic channel estimation,which outperformed than OMP.A*OMP is a pseudo-greedy algorithm,and can improve the problem of OMP algorithm falling into local *** though A*OMP has better performance than OMP,the channel estimation error cannot decrease as signal-to-noise ratio(SNR)*** solve the problem,the initialization procedure and termination criterion of A*OMP was modified for channel estimation,to select right initial searching path and avoid too many iterations which cause unknown *** on orthogonal frequency division multiplexing(OFDM)system,numerical simulation results showed that the pilot interval did not obviously affect the performance of the modified A**** there was no channel estimation error floor for the modified A**** error of the proposed algorithm was reduced by two and one orders of magnitude respectively from those of OMP and A**** proposed method outperformed the OMP and traditional A*OMP algorithm in both estimation accuracy and communication performance,with bit error rate(BER)reductions of 42.0%and 4.7%,respectively.

关键词： channel communication estimation

Perturbation characteristics of ambient sea noise caused by submerged objects

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Chinese Journal of Acoustics 2010年第2期29卷 141-151页

作者： LIN Jianheng YI Xuejuan YIN Baoyou guo shengming Key Laboratory of Underwater Acoustic Environment Chinese Academy of Sciences Beijing 100190 Qingdao Lab Institute of Acoustics Chinese Academy of Sciences Qingdao 266023

The perturbation characteristics of ambient sea noise field caused by scattering of submerged objects are discussed theoretically. Based on the sea noise source model with Gaussian-correlation amplitude, and applying the integral expressions for arbitrary source distribution and the spherical wave expression of Green function for a monopole in half-infinite space, the expressions of direct-arrival noise fields, scattering fields and total noise fields of a rigid spherical object under the irradiation of monopole and dipole sources, as well as the covariance among those noise fields at two receiving points are obtained. The numerical results of scattering directional patterns of rigid spherical objects and the visibility are given. It is shown that the total noise field is affected by not only the impedance characteristics of the object, the direction of receiver, but also the correlation between surface sources, and the interference between direct-arrival and scattering fields greatly. The results show that the sound visibility of a rigid spherical object is about 4-5 dB in near range and the scattering directivity characteristics of a rigid spherical object under the irradiation of surface sources are different from those of plane wave incidence.

关键词： Perturbation characteristics of ambient sea noise caused by submerged objects

Study of low bit rate speech codec algorithm in underwater acoustic communication

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Chinese Journal of Acoustics 2013年第4期32卷 411-424页

作者： XIAO Dong MO Fuyuan CHEN Geng guo shengming MA Li Key Laboratory of Underwater Acoustic Environment Chinese Academy of Sciences University of Chinese Academy of Sciences Institute of Acoustics Chinese Academy of Sciences

At medium or long distance （〉 10 kin） underwater acoustic speech communication, information transfer rate is constrained by the complicated, time varying channel and limited bandwidth. The bit rate of speech coding is required to be as low as possible. The time delay of underwater acoustic wave propagation can be used for low bit rate speech coding. After investigating the Mixed Excitation Linear Prediction （MELP） standard and taking account of the auditory perceptual features, a variable and adjustable bit rate speech codec algorithm has been proposed, whose average bit rate is about 600 bps. The average Perceptual Evaluation of Speech Quality Mean Opinion Score （PESQ MOS） of synthesized speeches is about 2.8. It has been proved by the computer simulation and sea trial that the performance of the proposed algorithm is well and robust when bit error rate is no more than 10-3. The synthesized speech is vivid and intelligible, and keeps main individual characteristics of speaker.

关键词： MELP Study of low bit rate speech codec algorithm in underwater acoustic communication rate

A methodology to achieve the basis function for the expansion of sound speed profile

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Chinese Journal of Acoustics 2014年第3期33卷 299-311页

作者： SONG Wenhua HU Tao guo shengming MA Li LU Licheng Key Laboratory of Underwater Acoustic Environment Chinese Academy of Sciences Institute of Acoustics Chinese Academy of Sciences University of Chinese Academy of Sciences

In order to evaluate the reliability and applicability of the Empirical Orthogonal Functions（EOFs）in the acoustic inversion of sound speed profile（SSP）and reduce EOF＇s dependence on the sample data,a methodology is proposed for the achievement of the basis functions for SSP＇s *** analyzing the oceanographic dynamics which is the main cause of the SSP＇s variation,the basis functions are obtained naming the Hydrodynamic Normal Modes（HNMs）.The HNM basis functions are almost the same as those derived from the EOF method,while HNMs has less dependence on the amount of the sample *** method has a physically meaningful interpretation,and it could give out the physical parameters which determine the basis functions for the expansion of SSP,and this makes it possible to analyze and evaluate the trustiness and applicability of EOFs.

关键词： A methodology to achieve the basis function for the expansion of sound speed profile SSP EOF

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利用声场简正波幅度起伏反演内波传播速度

哈尔滨工程大学学报 2020年第10期41卷 1518-1523页

作者：胡涛王臻郭圣明马力中国科学院水声环境特性重点实验室北京100190 中国科学院声学研究所北京100190 中国科学院大学北京100049

针对内波参数声学反演方法缺乏有效的试验验证问题,本文对Rouself等推导的单一内波环境下非线性内波速度与声场简正波起伏周期成正比关系的适用条件进行了讨论,提出多种内波共存环境下内波传播速度的声学反演方法,当非线性内波引起声场... 详细信息

针对内波参数声学反演方法缺乏有效的试验验证问题,本文对Rouself等推导的单一内波环境下非线性内波速度与声场简正波起伏周期成正比关系的适用条件进行了讨论,提出多种内波共存环境下内波传播速度的声学反演方法,当非线性内波引起声场简正波耦合时,可通过提取单阶简正波起伏周期来反演内波速度。利用2011年黄海内波(内潮和非线性内波)与声场起伏同步观测数据,成功实现了黄海内波传播速度的声学反演,验证了多种内波共存环境利用简正波幅度起伏反演内波传播速度的可行性。

关键词：黄海内潮非线性内波传播速度声场起伏简正波耦合简正波起伏周期声学反演

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空气中声源的水下匹配场定位

声学学报 2015年第6期40卷 799-806页

作者：苏林孙炳文郭圣明马力中国科学院声学研究所北京100190 中国科学院水声环境特性重点实验室北京100190 中国科学院大学北京100049

通过水下布放的垂直线列阵采集空中声源在水下激发的测量声场,采用声场波数积分模型(OASES模型)对空中声源激发的水下声场建模,计算出拷贝声场,将二者进行匹配处理从而对空中声源目标定位。首先通过数值仿真验证了匹配场处理技术对空中... 详细信息

通过水下布放的垂直线列阵采集空中声源在水下激发的测量声场,采用声场波数积分模型(OASES模型)对空中声源激发的水下声场建模,计算出拷贝声场,将二者进行匹配处理从而对空中声源目标定位。首先通过数值仿真验证了匹配场处理技术对空中声源的测距能力,并通过引入宽带匹配场处理器平滑掉距离上的周期性旁瓣。最后分析南海某海域的空气声试验数据,采用常规匹配场方法对700 m以内的32组空中声源目标进行定位,测距结果与GPS计算的收发间实际距离相比,大多数情况下是一致的,在较远距离由于信噪比降低,测量结果容易出现偏差。

关键词：匹配场定位水下声场空气声声源测距能力匹配场处理远距离积分模型

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作战任务分配建模及求解方法研究

系统仿真学报 2023年第4期35卷 887-898页

作者：马悦吴琳郭圣明国防大学北京100091 中国人民解放军31002部队北京100091

针对作战任务规划中的战前作战任务分配问题,构建了多约束作战任务分配模型以描述作战任务与作战单元之间的动态映射关系。提出了决策空间剪枝和约束条件判断等求解策略;阐述了决策变量编码、分配方案解码和分阶段适应值计算的方法,利... 详细信息

针对作战任务规划中的战前作战任务分配问题,构建了多约束作战任务分配模型以描述作战任务与作战单元之间的动态映射关系。提出了决策空间剪枝和约束条件判断等求解策略;阐述了决策变量编码、分配方案解码和分阶段适应值计算的方法,利用差分进化算法进行求解。实验表明:多约束分配模型及求解算法,能够有效降低决策空间规模,提高了分配方案的合理性和实用性。

关键词：作战任务分配作战任务规划多约束目标优化差分进化行为树