Results 21 to 30 of about 4,788,429 (284)

Signal processing in acoustic microscopy with applications to nondestructive evaluation

, 2022
S.413-422We present our recent results to use signal processing techniques to extend the capability of Acoustic Microscopy in nondestructive evaluation.
Arnold, W., Morsch, A.
core   +1 more source

Variable Scale Relative Entropy Detection for Non-Cooperative Underwater Acoustic Pulse Signals

IEEE Access, 2020
This work investigates the detection of non-cooperative underwater acoustic pulse signals at low signal-to-noise ratio (SNR). A variable scale relative entropy (VSRE) pulse signal detection scheme is proposed. Different from conventional relative entropy
Kun Wei, Shiliang Fang, Jun Tao
doaj   +1 more source

Parameter Estimation for Multi-Scale Multi-Lag Underwater Acoustic Channels Based on Modified Particle Swarm Optimization Algorithm

IEEE Access, 2017
The wideband underwater acoustic multipath channel can be modeled as a multi-scale multi-lag (MSML) channel because signals from different paths might experience different Doppler scales. This brings great challenge to channel parameter estimation.
Xing Zhang, Kang Song, Chunguo Li, Luxi Yang   +3 more
doaj   +1 more source

Improved Velocity Estimation Method for Doppler Sonar Based on Accuracy Evaluation and Selection

Journal of Marine Science and Engineering, 2021
The matched filtering method and the waveform-tracking method cannot maintain optimal velocity estimation performance all of the time. In order to solve this problem, this paper proposes an improved velocity estimation method for Doppler sonar, based on ...
Yongshou Yang, Shiliang Fang
doaj   +1 more source

A Review on Interception and Processing Techniques of Active Acoustic Radiated Signals from Small Underwater Targets

水下无人系统学报
With the rapid development of underwater unmanned platforms and miniaturized equipment, the demand for detecting and recognizing small underwater targets has become increasingly significant.
Zhizhen WANG, Xiaoyan WANG, Liang AN, Hongli CAO, Ronglai QIAN, Shiting YU, Chuanqi ZHU, Qixuan ZHU   +7 more
doaj   +1 more source

Blind Estimation of the PN Sequence of A DSSS Signal Using A Modified Online Unsupervised Learning Machine

Sensors, 2019
Direct sequence spread spectrum (DSSS) signals are now widely used in air and underwater acoustic communications. A receiver which does not know the pseudo-random (PN) sequence cannot demodulate the DSSS signal.
Yangjie Wei, Shiliang Fang, Xiaoyan Wang, Shuxia Huang   +3 more
doaj   +1 more source

Dynamic Optimization Method for Broadband ADCP Waveform with Environment Constraints

Sensors, 2021
Broadband acoustic Doppler current profiler (ADCP) is widely used in agricultural water resource explorations, such as river discharge monitoring and flood warning.
Yongshou Yang, Shiliang Fang
doaj   +1 more source

From Informed Independent Vector Extraction to Hybrid Architectures for Target Source Extraction

IEEE Open Journal of Signal Processing
This article revises informed independent vector extraction (iIVE) as a framework for connecting model-based blind source extraction (BSE) with deep learning. We introduce the contrast function for iIVE, which is derived by extending IVE with beamforming-
Zbynek Koldovsky, Jiri Malek, Martin Vratny, Tereza Vrbova, Jaroslav Cmejla, Stephen O'Regan   +5 more
doaj   +1 more source

Parameter Estimation of Delay-Doppler Underwater Acoustic Multi-Path Channel Based on Iterative Fractional Fourier Transform

IEEE Access, 2019
The characterization of wideband underwater acoustic (UWA) multi-path signals is investigated in this paper. The UWA multi-path channel can be considered as a sparse model and it causes changes of the transmitted signal on Doppler factor, time delay, and
Shuxia Huang, Shiliang Fang, Ning Han
doaj   +1 more source

Three-Dimensional Non-Uniform Sampled Data Visualization from Multibeam Echosounder Systems for Underwater Imaging and Environmental Monitoring

Remote Sensing
This paper proposes a method for visualizing three-dimensional non-uniformly sampled data from multibeam echosounder systems (MBESs), aimed at addressing the requirements of monitoring complex and dynamic underwater flow fields.
Wenjing Cao, Shiliang Fang, Chuanqi Zhu, Miao Feng, Yifan Zhou, Hongli Cao   +5 more
doaj   +1 more source