Results 21 to 30 of about 1,609 (180)
Stationauxiliary operation technology for sonar digital image processing based on machine vision [PDF]
Zhihui kongzhi yu fangzhenPassive sonar operator of a ship needs to concentrate on observing sonar interface and underwater or surface target situation for a long time to extract key information manually maritime operations when surface vessels pass through sensitive waters ...
DAI Zhonghua, JIN Qiaoyuan, YANG Ding, CHENG Yu
doaj +1 more source
Active Control of the Reflection Coefficient of an Underwater Surface
Acoustics, 2023 From a strategic point of view, it is essential to protect underwater vehicles from being detected by opponents. Modern mono- or bistatic sonar systems are capable of precisely determining the position of a watercraft.
Johannes Timmermann +2 more
doaj +1 more source
Wake-Responsive AUV Guidance Assisted by Passive Sonar Measurements
Journal of Marine Science and EngineeringTo make an Autonomous Underwater Vehicle (AUV) chase a moving target ship that generates wake, wake-responsive guidance can be used. This scenario is applicable to making an underwater torpedo pursue a moving target ship until hitting the target.
Jonghoek Kim
doaj +1 more source
Underwater Tone Detection with Robust Coherently-Averaged Power Processor
Journal of Marine Science and Engineering, 2022 The detection of tonal signals with unknown frequencies is an important area of study in underwater signal processing. A common approach to address this issue is to use the Discrete Fourier Transform (DFT) for observations.
Qichen Xie +5 more
doaj +1 more source
Research advances and development trends in acoustic target detection
Zhongguo Jianchuan YanjiuUnderwater target detection faces severe challenges due to the enhanced acoustic stealth capabilities of targets and the anomalous sound propagation phenomena within complex ocean waveguides.
Yixin YANG +5 more
doaj +1 more source
Multi-Stage Feature Extraction and Classification for Ship-Radiated Noise
Sensors, 2021 Due to the complexity and unique features of the hydroacoustic channel, ship-radiated noise (SRN) detected using a passive sonar tends mostly to distort. SRN feature extraction has been proposed to improve the detected passive sonar signal. Unfortunately,
Hamada Esmaiel +5 more
doaj +1 more source
Photonic Neuromorphic Processing With Coupled Spiking Silicon Microrings
Laser &Photonics Reviews, EarlyView.A neuromorphic photonic core composed of three self‐pulsing silicon microring resonators is experimentally demonstrated for analogue and digital processing. Richer computational capabilities emerge under injection conditions where the dynamics are nonlinear and coupled, yet remain reproducible, opening novel strategies for future on‐chip training and ...
Giovanni Donati +3 more
wiley +1 more source
Journal of Marine Science and Engineering, 2023 In submarine warfare systems, passive SONAR is commonly used to detect enemy targets while concealing one’s own submarine. The bearing information of a target obtained from passive SONAR can be accumulated over time and visually represented as a two ...
Won Shin, Da-Sol Kim, Hyunsuk Ko
doaj +1 more source
FLSea: Underwater Visual–Inertial and Stereovision Forward‐Looking Data Sets
Journal of Field Robotics, EarlyView.ABSTRACT Visibility underwater is challenging and degrades as the distance between the subject and the camera increases. That is why forward‐looking underwater computer vision tasks are difficult. We have collected underwater forward‐looking stereovision and visual–inertial image sets using two underwater imaging platforms, a stereo camera rig, and an ...
Yelena Randall +2 more
wiley +1 more source
A Broadband Beamformer Suitable for UUV to Detect the Tones Radiated from Marine Vessels
Sensors, 2018 In this paper, the issue that the underwater unmanned vehicle (UUV) with a sonar array achieves the passive detection of vessel targets by detecting the tones radiated from the targets is considered.
Shilong Ma +3 more
doaj +1 more source