Results 1 to 10 of about 4,800,869 (233)

The Tacotron-Based Signal Synthesis Method for Active Sonar [PDF]

Sensors, 2022
The importance of active sonar is increasing due to the quieting of submarines and the increase in maritime traffic. However, the multipath propagation of sound waves and the low signal-to-noise ratio due to multiple clutter make it difficult to detect ...
Yunsu Kim, Juho Kim, Jungpyo Hong, Jongwon Seok   +3 more
doaj   +3 more sources

Behavioural responses of fin whales to military mid-frequency active sonar [PDF]

Royal Society Open Science, 2023
The effect of active sonars on marine mammal behaviour is a topic of considerable interest and scientific investigation. Some whales, including the largest species (blue whales, Balaenoptera musculus), can be impacted by mid-frequency (1–10 kHz) military
Brandon L. Southall, Ann N. Allen, John Calambokidis, Caroline Casey, Stacy L. DeRuiter, Selene Fregosi, Ari S. Friedlaender, Jeremy A. Goldbogen, Catriona M. Harris, Elliott L. Hazen, Valentin Popov, Alison K. Stimpert   +11 more
doaj   +3 more sources

Bio-Inspired Covert Active Sonar Strategy [PDF]

Sensors, 2018
The covertness of the active sonar is a very important issue and the sonar signal waveform design problem was studied to improve covertness of the system.
Jiajia Jiang, Xianquan Wang, Fajie Duan, Chunyue Li, Xiao Fu, Tingting Huang, Lingran Bu, Ling Ma, Zhongbo Sun   +8 more
doaj   +4 more sources

A Phase-Coded Sequence Design Method for Active Sonar [PDF]

Sensors, 2020
Phase-coded sequences are widely studied as the transmitted signals of active sonars. Recently, several design methods have been developed to generate phased-coded sequences satisfying specific aperiodic or periodic autocorrelation sidelobe level metrics.
Chengyu Guan, Zemin Zhou, Xinwu Zeng
doaj   +3 more sources

Pulsed Active Sonar Using Generalized Sinusoidal Frequency Modulation for High-Speed Underwater Target Detection and Tracking

IEEE Access, 2023
For decades, the soft-kill strategy which detects high-speed underwater targets with passive sonar and attract the targets using decoys has been used. However, recently, the paradigm to respond to the high-speed underwater targets is shifting to a hard ...
Jinuk Park, Geunhwan Kim, Jongwon Seok, Jungpyo Hong   +3 more
doaj   +2 more sources

Unsupervised active sonar contact classification through anomaly detection

EURASIP Journal on Advances in Signal Processing, 2023
Target detection and sonar contact classification with active sonar systems are not trivial especially when operating in coastal and shallow water environments with multipath propagation, high reverberation and clutter. It is even more difficult when the
Pietro Stinco, Alessandra Tesei, Kevin D. LePage   +2 more
doaj   +2 more sources

Study on Small Samples Active Sonar Target Recognition Based on Deep Learning

Journal of Marine Science and Engineering, 2022
Underwater target classification methods based on deep learning suffer from obvious model overfitting and low recognition accuracy in the case of small samples and complex underwater environments.
Yule Chen, Hong Liang, Shuo Pang
doaj   +2 more sources

Active Object Detection in Sonar Images [PDF]

IEEE Access, 2020
Object detection in sonar images has always been a challenge due to the low resolution of sonar images and the strong noise existing in them. Although convolutional neural networks (CNNs) have been applied to detect objects in sonar images, successful ...
Longyu Jiang, Tao Cai, Qixiang Ma, Fanjin Xu, Shijie Wang   +4 more
doaj   +2 more sources

Severity Scoring of Behavioral Responses of Sperm Whales (Physeter macrocephalus) to Novel Continuous versus Conventional Pulsed Active Sonar

Journal of Marine Science and Engineering, 2021
Controlled exposure experiments (CEEs) have demonstrated that naval pulsed active sonar (PAS) can induce costly behavioral responses in cetaceans similar to antipredator responses. New generation continuous active sonars (CAS) emit lower amplitude levels
Charlotte Curé, Saana Isojunno, Marije L. Siemensma, Paul J. Wensveen, Célia Buisson, Lise D. Sivle, Benjamin Benti, Rune Roland, Petter H. Kvadsheim, Frans-Peter A. Lam, Patrick J. O. Miller   +10 more
doaj   +2 more sources

Active sonar target recognition method based on multi‐domain transformations and attention‐based fusion network

IET Radar, Sonar & Navigation
The classification and recognition of underwater targets by an active sonar system remain challenging and complex. Traditional methods have limited classification performance in time and spatially varying ocean channels.
Qingcui Wang, Shuanping Du, Wei Zhang, Fangyong Wang   +3 more
doaj   +2 more sources