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Estimation of target depth using deep-sea echo multipath structure matching

Chinese Journal of Acoustics 2023年第3期42卷 251-269页

作者： ZHANG Fengzhen LI Guijuan HU Wenshuai HU Chen Key Laboratory of Science and Technology on Underwater Test and Control Dalian 116013 Dalian Scientific Test and Control Technology Institute Dalian 116013

This paper presents a method to estimate the depth of deep-sea target by matching the time delay and amplitude structure of echo multipath highlight *** echo structure is the convolution of two-way channel transfer function as well as the acoustic scattering function of the target,which shows the characteristics of deep-sea highlight clusters when the target is close to the sea surface or near the sea *** time delay and amplitude structure of highlight clusters are related to the target depth,which can be used to estimate the target depth.A method of matching estimation of target depth on range-depth grid using nonlinear programming cost function is *** mismatch effects of inter-cluster time delay interval deviation and sea water sound velocity profile deviation on matching estimation are simulated and *** results of a winter experiment in the South China Sea illustrate that when the water depth is 1 km and distance is 5–8 km,the echo of target is 40 m underwater,there are three highlight clusters with a time interval of about 0.3 s,with the error range of target depth matching estimation being 0–65 m.

关键词： matching structure estimation

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Multivariate Multiscale Sample Entropy for Multi-Channel underwater Acoustic Signal Analysis 7

Multivariate Multiscale Sample Entropy for Multi-Channel Und...

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7th IEEE Information technology, Networking, Electronic and Automation control Conference, ITNEC 2024

作者： Zhou, Jing Li, Yaan Wang, Mingzhou Shi, Lei School of Marine Science and Technology Northwestern Polytechnical University Xi'an China Xi'an Precision Machinery Research Institute National Key Laboratory of Underwater Information and Control Xi'an China

ISBN: (纸本)9798350370782

Multi-channel time series collected by arrays are prevalent in underwater acoustic signal processing and are crucial for uncovering the intrinsic characteristics of the observed system. This paper introduces the multivariate multiscale sample entropy (MMSE) to assess the complexity information in multi-channel underwater acoustic signals. Simulation analysis is employed to validate the effectiveness of the MMSE algorithm in extracting both within-channel and cross-channel information from multi-channel signals. Various types of simulated ship-radiated noise are generated to illustrate the MMSE algorithm's capability to differentiate between signals. Additionally, we employ MMSE to analyze various real-world signals, including ship-radiated noise, ambient noise, and interface reverberation. The MMSE results demonstrate its proficiency in differentiating various underwater acoustic signals compared to traditional frequency domain methods. © 2024 IEEE.

关键词： Frequency domain analysis

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Full-Space Beam Scanning Antenna Based on Spoof Surface Plasmon Polaritons

Full-Space Beam Scanning Antenna Based on Spoof Surface Plas...

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2023 International Applied Computational Electromagnetics Society Symposium, ACES-China 2023

作者： Wu, Zhicheng Kong, Xianglin Wang, Jun Xu, Ruofeng Zhao, Lei Xu, Yinfang School of Information and Control Engineering China University of Mining and Technology Xuzhou China National Key Laboratory of Science and Technology on Test Physics and Numerical Mathematics Beijing China

ISBN: (纸本)9781733509657

In this paper, a full-space beam scanning antenna based on spoof surface plasmon polaritons (SSPPs) is proposed. The proposed antenna is composed of a SSPPs loaded by the varactor diodes and periodic metallic patches. The periodic patches can transform the slow waves from SSPPs into fast waves, and the cutoff frequency can be reconfigured by changing the capacitance of the varactor diode, which will make the radiation angle of the beam change within a fixed frequency. Simulation results show that the radiation angle ranges from -90° to 90° at 9 GHz. © 2023 Applied Computational Electromagnetics Society (ACES).

关键词： Scanning antennas

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Impact of Evaporation Duct on Electromagnetic Wave Propagation During a Typhoon

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Journal of Ocean University of China 2022年第5期21卷 1069-1083页

作者： WANG Shuwen YANG Kunde SHI Yang YANG Fan ZHANG Hao School of Marine Science and Technology Northwestern Polytechnical UniversityXi’an 710072China Key Laboratory of Ocean Acoustics and Sensing Northwestern Polytechnical UniversityMinistry of Industry and Information TechnologyXi’an 710072China National Key Laboratory of Underwater Information Processing and Control Xi’an 710072China

The evaporation duct,a result of evaporation from the ocean,is a region above the sea surface in which radio waves are refracted *** duct has strong effects on microwave *** cause huge anomalies in marine meteorological parameters that influence the evaporation duct distribution and structure,which in turn affects the propagation of electromagnetic(EM)***,EM wave propagation under the typhoon process has seldom been ***,taking Typhoon Phanfone(201929)as an example,this study uses a dataset from the European Centre for Medium-Range Weather Forecasts,combined with the Naval Atmospheric Vertical Surface Layer Model and the parabolic equation model,to study the evaporation duct’s impact on EM wave propagation during a *** spatial and temporal path loss distributions reveal that large amounts of EM wave energy are emitted from the evaporation duct when the EM wave passes through a typhoon *** average,a typhoon eye causes an approximately 20 dB increase in path loss for EM wave propagation at low antenna ***,the effects of a typhoon eye on EM wave propagation at different signal frequencies and antenna heights are *** results show that a typhoon has a larger impact on EM wave propagation with low signal frequency and high antenna height.

关键词： evaporation duct typhoon ECMWF wave glider electromagnetic wave propagation

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Source-Configured Microwave Plasmonic Vortices Based on Single Meta-Particle

Source-Configured Microwave Plasmonic Vortices Based on Sing...

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2023 International Applied Computational Electromagnetics Society Symposium, ACES-China 2023

作者： Kong, Xianglin Zhao, Lei Shen, Xiaopeng Xu, Yinfang School of Information and Control Engineering China School of Materials Science and Physics China University Mining and Technology Xuzhou China National Key Laboratory of Science and Technology on Test Physics & Numerical Mathematics Beijing China

ISBN: (纸本)9781733509657

In this paper, generation of plasmonic vortices with tunable topologic charges is proposed in the microwave regime. Tunable vortices with topologic charges of 0, +1 and -1 can be configured by illuminating incident plane waves with linearly polarization (LP), left-circularly polarization (LHCP) and right-circularly polarization (RHCP) on a single meta-particle, respectively. A spiral meta-particle operating at 2.94 GHz is designed, fabricated and measured to demonstrate the source-configured characteristics. The results showed that simulation and test are consistent with the theoretical ones. © 2023 Applied Computational Electromagnetics Society (ACES).

关键词： Vortex flow

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Hybrid signal fusion for target detection in distributed PA-MIMO radar systems on moving platforms

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IEEE Transactions on Aerospace and Electronic Systems 2025年

作者： Zhou, Dingsen Yang, Minglei Lian, Hao Greco, Maria Sabrina Gini, Fulvio Xidian University National Key Laboratory of Radar Signal Processing Shaanxi Xi'an710071 China Science and Technology on Underwater Test and Control Laboratory Dalian116013 China University of Pisa Department of Information Engineering Pisa56122 Italy

Distributed phased multiple-input multiple-output (PA-MIMO) radar systems on moving platforms combine the spatial diversity of MIMO radars with the coherent gain of phased-array radars, making them ideal for dynamic environments. However, challenges such as motion-induced channel variability, Doppler shifts, and complex parameter estimation often hinder target detection. Traditional methods like non-coherent fusion (NCF) and coherent fusion (CF) struggle to adapt to such variability, leading to suboptimal performance. In this paper, we propose a hybrid signal fusion (HSF) scheme that integrates joint space-time-phase compensation (JSTPC) with a compressed fusion network. The JSTPC module mitigates motion-induced phase errors and ensures precise alignment of received signals, while the compressed fusion network combines CF and NCF stages, leveraging their respective strengths to adaptively manage channel correlation variability. We also develop a joint parameter estimation algorithm to accurately extract direction of departure, direction of arrival, and Doppler frequency, thereby ensuring precise signal reconstruction and enhancing the detection process by estimating key parameters in real time. Theoretical analyses of detection thresholds and probabilities, derived using moment-matching techniques, further validate the reliability of the proposed scheme. Monte Carlo simulations and theoretical analyses for diverse radar configurations and channel correlation scenarios show that the proposed HSF scheme achieves 2 dB detection gain improvement over NCF. © 2025 IEEE.

关键词： Frequency estimation

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A Radar Signal Modulation Recognition Algorithm Based on Multi-branch Fusion Difference 6

A Radar Signal Modulation Recognition Algorithm Based on Mul...

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6th IEEE International Conference on Electronic Information and Communication technology, ICEICT 2023

作者： Jiang, Sisi Gao, Jingpeng Jiang, Zhiye Ye, Fang College of Information and Communication Engineering Harbin Engineering University Harbin China Beijing Institute of Space Long March Vehicle National Key Laboratory of Science and Technology on Test Physics and Numerical Mathematics Beijing China College of Information and Communication Engineering Harbin Engineering University National Key Laboratory of Underwater Acoustic Technology Harbin China

ISBN: (纸本)9798350399059

The time-frequency images of radar modulation signals are similar at low signal-to-noise ratios, which will lead to lower recognition accuracy. This paper proposes an algorithm based on multi-branch fusion differences to identify radar modulation signals. The algorithm designs a multi-branch fusion differential module based on the attention mechanism and differential thinking, to extract time-frequency image fine-grained features and improve the Convolution Neural Network characterization ability. After that, a dual-branch differential network is proposed by combining vanilla convolution and multi-branch fusion difference module. The network can fuse global and detailed features of time-frequency images, which can achieve radar signal modulation recognition. The simulation results show that the recognition accuracy of the algorithm can reach 93.17% at 0dB. Therefore, the algorithm can obtain high recognition accuracy and has high recognition performance. © 2023 IEEE.

关键词： Convolution

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Coupled analysis of Braceless semi-submersible offshore wind turbine under different water depths 32nd

Coupled analysis of Braceless semi-submersible offshore wind...

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32nd International Ocean and Polar Engineering Conference, ISOPE 2022

作者： Zhou, Zhimin Wang, Xianzhi Zhou, Xiangbo Qiao, Dongsheng Yan, Jun Ning, Dezhi Science and Technology on Underwater Test and Control Laboratory the 760th Research Institute of China Shipbuilding Industry Corporation Dalian China State Key Laboratory of Coastal and Offshore Engineering Dalian University of Technology Dalian China

ISBN: (纸本)9781880653814

Braceless semi-submersible floating offshore wind turbine (FOWT) is subjected to environmental loads during its service, and the different combinations of wind, wave, and current environmental loads have different contributions to the motion responses of the offshore wind turbine platform. Under the different water depth of 100m, 150m, 200m, the time domain motion response calculation model of floating wind turbine platform was established, and the corresponding time-domain motion of wind turbine platform with six degrees of freedom and the mooring line tension were analyzed. The results show that the maximum motion response and mooring line tension are all in line with the engineering requirements. The results of this study provide reference for further research on the design of mooring system. © 2022 by the International Society of Offshore and Polar Engineers (ISOPE).

关键词： Semisubmersibles

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Object Detection and Multiple Objective Optimization Manipulation Planning for underwater Autonomous Capture in Oceanic Natural Aquatic Farm

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Journal of Field Robotics 2025年第0期

作者： Hai, Huang Tao, Jiang Xinyu, Bian Hao, Zhou Xu, Yang Gang, Wang Hongde, Qin Xinyue, Han National Key Laboratory of Science and Technology on Underwater Vehicle Harbin Engineering University Harbin China State Key Laboratory of Management and Control for Complex System Institute of Automation Chinese Academy of Science Bei Jing China

underwater autonomous capture operations offer significant potential for reducing labor and health risks in sea organism industries. This study presents a comprehensive solution for cross-domain underwater object detection and autonomous capture. A novel unsupervised domain adaptive learning method is proposed, integrating multiscale domain adaptive modules and attention mechanisms into a Faster Region-Convolutional Neural Network framework. This approach enhances feature alignment across diverse aquatic domains without parameter tuning. Additionally, an efficient, parameterless constrained multiobjective optimization algorithm is introduced for underwater autonomous mobile capture, integrating parameterized trajectory planning with innovative features, such as adaptive mutation strategies and constraint violation tolerance. The proposed approaches are extensively validated through simulations, tank experiments, and real-world oceanic trials in the Natural Aquatic Farm of Zhangzidao Island. Results demonstrate the system's robustness in complex underwater environments with varying currents, with experimental outcomes validating the accuracy and reliability of detection and capture capabilities. This research significantly advances autonomous underwater systems' capabilities in object detection and capture tasks, addressing complex challenges in realistic organism capture applications across diverse aquatic environments. © 2025 Wiley Periodicals LLC.

关键词： Health risks

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Characterization and prediction of tailpipe ammonia emissions from in-use China 5/6 light-duty gasoline vehicles

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Frontiers of Environmental science & Engineering 2024年第1期18卷 71-81页

作者： Lewei Zeng Fengbin Wang Shupei Xiao Xuan Zheng Xintong Li Qiyuan Xie Xiaoyang Yu Cheng Huang Qingyao Hu Yan You Ye Wu College of Chemistry and Environmental Engineering Shenzhen UniversityShenzhen 518060China State Key Laboratory of Engines Tianjin UniversityTianjin 300072China China Automotive Technology and Research Center Co.Ltd. Tianjin 300300China CATARC Automotive Test Center(Guangzhou)Co.Ltd. Guangzhou 511300China State Environmental Protection Key Laboratory of Cause and Prevention of Urban Air Pollution Complex Shanghai Academy of Environmental SciencesShanghai 200233China National Observation and Research Station of Coastal Ecological Environments in Macao Macao Environmental Research InstituteMacao University of Science and TechnologyMacao SAR 999078China School of Environment State Key Joint Laboratory of Environment Simulation and Pollution ControlTsinghua UniversityBeijing 100084China

On-road tailpipe ammonia (NH3) emissions contribute to urban secondary organic aerosol formation and have direct or indirect adverse impacts on the environment and human health. To understand the tailpipe NH3 emission characteristics, we performed comprehensive chassis dynamometer measurements of NH3 emission from two China 5 and two China 6 light-duty gasoline vehicles (LDGVs) equipped with three-way catalytic converters (TWCs). The results showed that the distance-based emission factors (EFs) were 12.72 ± 2.68 and 3.18 ± 1.37 mg/km for China 5 and China 6 LDGVs, respectively. Upgrades in emission standards were associated with a reduction in tailpipe NH3 emission. In addition, high NH3 EFs were observed during the engine warm-up period in cold-start cases owing to the intensive emissions of incomplete combustion products and suitable catalytic temperature in the TWCs. Notably, based on the instantaneous NH3 emission rate, distinct NH3–emitting events were detected under high/extra high velocity or rapid acceleration. Furthermore, NH3 emission rates correlated well with engine speed, vehicle specific power, and modified combustion efficiency, which were more easily accessible. These strong correlations were applied to reproduce NH3 emissions from China 5/6 LDGVs. The predicted NH3 EFs under different dynamometer and real-world cycles agreed well with existing measurement and prediction results, revealing that the NH3 EFs of LDGVs in urban routes were within 8.55–11.62 mg/km. The results presented here substantially contribute to improving the NH3 emission inventory for LDGVs and predicting on-road NH3 emissions in China.

关键词： NH3 instantaneous emissions Catalytic temperature Vehicle specific power Combustion efficiency Emission prediction

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