Results 21 to 30 of about 9,271 (162)

Using High-Order Particle Velocity Gradient Polarization Characteristics to Detect Underwater Coherent Interference

Journal of Marine Science and Engineering, 2023
Detection of underwater coherent interference is necessary as its presence affects the estimation of the desired target. In this work, a method based on high-order particle velocity gradient polarization characteristics is proposed to distinguish the ...
Di Wu, Lanyue Zhang, Jia Wang, Xueru Hu
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Improved high-precision approach based on deconvolution in MIMO sonar imagery

The Journal of Engineering, 2019
Multiple-input multiple-output (MIMO) sonar enables high-resolution imaging, which is extremely useful in underwater acoustic high-precision imagery.
Lu Yan, Shengchun Piao, Feng Xu
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A Spatially Fair and Low Conflict Medium Access Control Protocol for Underwater Acoustic Networks

Journal of Marine Science and Engineering, 2023
The large propagation delay in underwater acoustic networks results in spatial and temporal uncertainty between communication links. This uncertainty, in turn, leads to problems with spatial unfairness and packet collision in media access control (MAC ...
Maochun Zheng, Wei Ge, Xiao Han, Jingwei Yin   +3 more
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Passive tracking in underwater acoustic [PDF]

Signal Processing, 2002
This paper provides a novel passive underwater acoustic method to track a moving object, called a source or target, with the following constraints: the sensor's location is fixed and imposed, and classical array processing techniques cannot be applied.
Bernard Xerri, Jean-François Cavassilas, Bruno Borloz   +2 more
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Mutual Information Re-Registration of Sensitive Region in Forward-Looking Sonar Images Combined With Particle Swarm Optimization Algorithm

IEEE Access, 2021
In order to meet the needs of complex seafloor scenes target detection, an image registration method based on sensitive region is proposed which considering the fuzzy boundary, poor contrast and low overall gray value of forward-looking sonar image.
Mingzhe Wei, Hongyu Bian, Shengquan Li, Feng Zhang   +3 more
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Scene-Driven Semantic Alignment for Generative Communication in Underwater Images

IET Signal Processing
Underwater images serve as one of the most intuitive media for human perception of underwater environments. However, the limited bandwidth and susceptibility to noise in underwater acoustic (UWA) channels pose significant challenges for traditional image
Yuetong Li, Zhenyu Jia, Yuyang Peng, Yi Zhu, Fei Yuan   +4 more
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Multimodal superposition modeling and acoustic field characteristics analysis of scattering sound field from spherical targets

AIP Advances
In this paper, a multimodal superposition model of the scattered acoustic field from a spherical target is investigated and the distribution laws of the scattered acoustic field of different sizes of rigid and elastic spheres at different frequencies are
Ruoyun Xing, Jianjun Zhu, Shuhan Ming, Haotian Gu, Peihong Wang   +4 more
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The sound source identification of elastic network regularized generalized inverse beamforming based on iterative shrinkage thresholding

Xibei Gongye Daxue Xuebao
In this paper, aiming at the problem of noise source location of underwater targets, considering the spatial sparsity of sound sources, the elastic network regularization generalized inverse beamforming with iterative shrinkage threshold is employed to ...
HE Huihui, WANG Xinyu, WU Xiaofei, ZHANG Jianqiang, SHI Shengguo   +4 more
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The influence of impedance mismatch of the medium with gradient change of impedance on acoustic characteristics [PDF]

MATEC Web of Conferences, 2019
Medium with gradient change of acoustic impedance is a new type acoustic structure. It is composed of several materials and has a continuous gradient composition and structure whose specific acoustic impedance varies smoothly across the layer.
Hu Bo, Wang Moran, Du Yimei
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Underwater Acoustic Channel Estimation via an Orthogonal Matching Pursuit Algorithm Based on the Modified Phase-Transform-Weighted Function

Journal of Marine Science and Engineering, 2023
In the context of torpedo guidance systems, the performance of active sonar in channel parameter estimation and target detection and recognition is significantly degraded by the multipath effect and the time-varying characteristics of the underwater ...
Xueru Hu, Lanyue Zhang, Di Wu, Jia Wang
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