Results 61 to 70 of about 1,609 (180)

Visualisation forms in passive sonar with towed array

Archives of Acoustics, 2014
This paper presents forms of visualisation used in modern underwater systems, a topic covered at two previous Seminars. This year’s presentation describes how imaging is organised on the monitors of a passive sonar with a long acoustic array, towed ...
A. Raganowicz, L. Kilian, J. Marszal, Z. Ostrowski, A. Schmidt   +4 more
doaj  

Machine Learning Ship Classifiers for Signals from Passive Sonars

Applied Sciences
The accurate automatic classification of underwater acoustic signals from passive SoNaR is vital for naval operational readiness, enabling timely vessel identification and real-time maritime surveillance.
Allyson A. da Silva, Lisandro Lovisolo, Tadeu N. Ferreira   +2 more
doaj   +1 more source

BTSTNet: A Beamforming-Based Target Separation Transformer Network for Passive SONAR

IEEE Access
Passive SONAR has attracted significant attention in covert operations, enabling vessel detection and classification through spectrogram analysis of received signals without active transmission. However, in realistic ocean environments, interference from
Yeonbi Jeong, Chanjun Chun, Yongguk Kim, Yeongseo Shin, Wonyeol Kim   +4 more
doaj   +1 more source

Wavelet-Enhanced DEMON Processing and Deep Learning for Passive SONAR Target Recognition

Wadi Alshatti University Journal of Pure and Applied Sciences
This paper presents an integrated underwater Automatic Target Recognition (ATR) framework that synergizes advanced signal processing with deep learning.
Saaida Alnour, Marai Abousetta
doaj   +1 more source

Two-dimensional DOA estimation based on thin array towed by a small autonomous platform

Journal of Measurement Science and Instrumentation, 2021
The small autonomous platform with a thin line array is an important tool for underwater acoustic mobile surveillance. Generally, only one-dimensional（1-D） direction-of-arrival（DOA） of the source signal can be estimated using a thin towed line array.
JIANG Jiajia, YANG Guoliang, LI Chunyue, LI Yao, WANG Xianquan, SUN Zhongbo, DUAN Fajie, FU Xiao   +7 more
doaj  

Hybrid Log-Mel and HPSS-Aided Convolutional Neural Network for Underwater Very-Low-Frequency Remote Passive Sonar Detection

Journal of Marine Science and Engineering
Very-low-frequency (VLF) passive sonar detection is one of the core technologies for maritime surveillance, although its performance is often severely affected by strong impulsive ocean ambient noise interference. This paper, for the first time, proposes
Haitao Dong, Lijian Yang, Yuan Liu, Siyuan Li   +3 more
doaj   +1 more source

A Dynamic Evaluation Method for Collaborative Search Efficiency of Multi-Sonar Systems Under Uncertain Situations

Applied Sciences
In sonar collaborative search tasks, effectively evaluating the collaborative search efficiency is an important way to measure whether a task can be successful, which can also provide strong support for optimizing search schemes.
Shizhe Wang, Weiyi Chen, Zongji Li, Xu Chen   +3 more
doaj   +1 more source

A Fully Complex-Valued Underwater Acoustic Signal Enhancement Model for Passive Sonar Systems

IEEE Open Journal of Signal Processing
Passive sonar systems offer stealth and low-energy consumption advantages while facing highly complex signal conditions. Underwater acoustic signal (UWAS) enhancement for passive sonar systems aims to improve the quality of vessel-radiated signals ...
Zhengzhe Zhang, Jie Zhang, Haoyin Yan, Hengshuang Liu, Junhua Liu   +4 more
doaj   +1 more source

Automatic LOFAR Line-Spectrum Extraction with Hybrid Dataset Construction and a Continuity-Aware U-Net

Journal of Marine Science and Engineering
Line-spectrum features in ship-radiated noise are essential for the analysis and recognition of passive sonar targets. Robust automatic extraction from low-frequency analysis and recording (LOFAR) spectrograms remains challenging in underwater acoustic ...
Zhongdi Liu, Chenmu Li, Bin Zhou, Qiming Ma, Liang Xie   +4 more
doaj   +1 more source

Shifting responses of goose-beaked whales (Ziphius cavirostris) to long-standing naval sonar exposure opens new perspectives for research and mitigation

Scientific Reports
Predicting and mitigating the impacts of chronic noise on marine mammals is limited by sparse data on repeated disturbance. Naval sonar disrupts species behavior with lethal and sublethal risks, yet mitigation relies on short-term studies.
Alba Solsona-Berga, Jennifer S. Trickey, Charles G. M. Paxton, Ana Širović, Cornelia S. Oedekoven, Marie A. Roch, Len Thomas, Sean M. Wiggins, John A. Hildebrand, Simone Baumann-Pickering   +9 more
doaj   +1 more source