Results 71 to 80 of about 4,296,969 (159)

Dictionary learning for sparse representation and classification of sound speed profile in the ocean

, 2022
Badiey, MohsenWan, LinThe presence of internal waves (IWs) in the ocean alters the variability of sound speed profile (SSP) in the water column and plays an important role in applications such as underwater acoustics.
Castro-Correa, Jhon Alejandro
core   +1 more source

Nonlinear modeling of the 3-D ocean sound speed field via incremental sample convolutional exchange network

Applied Ocean Research
The accurate construction of the underwater sound speed fields (SSFs) is critical for systems of positioning, navigation, timing, and communication (PNTC).
Kequan Shi, Qi Li, Pan Xu, Bingbing Zhang, Hongna Zhu   +4 more
doaj   +1 more source

Influence of Range-Dependent Sound Speed Profile on Position of Convergence Zones

, 2022
Based on the Wentze–Kramers–Brillouin approximation, we derive formulae to calculate the position of convergence zones in a range-dependent environment with sound speed profiles varying in linear and ellipsoidal Gaussian eddy cases.
Ziyang Li, Shengchun Piao, Lijia Gong, Minghui Zhang   +3 more
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Ranging in an Underwater Medium with Multiple Isogradient Sound Speed Profile Layers

Sensors, 2012
In this paper, we analyze the problem of acoustic ranging between sensor nodes in an underwater environment. The underwater medium is assumed to be composed of multiple isogradient sound speed profile (SSP) layers where in each layer the sound speed is ...
Hamid Ramezani, Geert Leus
doaj   +1 more source

Expendable Conductivity–Temperature–Depth-Assisted Fast Underwater Sound Speed Estimation by Convolutional Neural Network with Reduced Fully Connected Layers

Journal of Marine Science and Engineering
Obtaining accurate sound speed profiles (SSPs) in near-real-time is of great significance for ocean exploration, underwater communication and improving the performance of sonar systems.
Sijia Li, Hao Zhang, Jiajun Lu, Pengfei Wu, Wei Huang   +4 more
doaj   +1 more source

Research and experimental verification on low-frequency long-range underwater sound propagation dispersion characteristics under dual-channel sound speed profiles in the Chukchi Plateau [PDF]

, 2023
The dual-channel sound speed profiles of the Chukchi Plateau and the Canadian Basin have become current research hotspots due to their excellent low-frequency sound signal propagation ability.
Weng, Jinbao, Wen, Hongtao, Xue, Ruichao, Qi, Yubo, Zhou, Hongtao, Yang, Yanming   +5 more
core  

CRGAN-based turbo code interleaver for underwater acoustic communications

ICT Express
This paper proposes a channel response generative adversarial network (CRGAN)-based turbo code interleaver that estimates a channel response and interleaver indices at a transmitter by using a sound speed profile (SSP) and the ocean environments without ...
Yongcheol Kim, Seunghwan Seol, Jaehak Chung, Hojun Lee   +3 more
doaj   +1 more source

Effects of inadequate surface sound speed measurements in multibeam echosounder systems [PDF]

, 2007
In any type of survey work, variation of the characteristics of the medium through which the measurements are made is a challenge, thus; having serious effects on the accuracy of the measurements.
Mahmud, Mohd. Razali, M. D. E. K., Gunathilaka   +1 more
core  

Inversion of Sound Speed Profile Controlled by Sparse Observations: Research Background, Current Status and Technical Analysis

Oceans
The sound speed profile (SSP) is a core environmental parameter for underwater acoustic detection, navigation, communication, and other applications. However, its accurate acquisition is constrained by the sparsity of observational data and the ill-posed
Haopeng Fan, Shuling Xie, Shuqiang Xue
doaj   +1 more source

Unsynchronized Underwater Localization With Isogradient Sound Speed Profile and Anchor Location Uncertainties

Precise underwater localization has been very challenging due to the unsynchronized clock, stratification effect, and anchor location uncertainties. Although some localization methods have been proposed, they are all based on very strong and certain ...
Li, Cheng, Gong, Zijun, Yan, Jing, Guan, Xinping, Zhao, Haiyan   +4 more
core   +1 more source