Results 21 to 30 of about 401,492 (244)
Time-frequency represetation of radar signals using Doppler-Lag block searching Wigner-Ville distribution [PDF]
, 2018 Radar signals are time-varying signals where the signal parameters change over time. For these signals, Quadratic Time-Frequency Distribution (QTFD) offers advantages over classical spectrum estimation in terms of frequency and time resolution but it ...
Hamdi, Muhammad Noor Muhammad +1 more
core +3 more sources
Using Differential Geometry to Revisit the Paradoxes of the Instantaneous Frequency
IEEE Open Access Journal of Power and Energy, 2022 This paper proposes a general framework to interpret the concept of Instantaneous Frequency (IF) in three-phase systems. The paper first recalls the conventional frequency-domain analysis based on the Fourier transform as well as the definition of IF ...
Federico Milano +4 more
doaj +1 more source
Machines, 2022 The vibration signal from the rotatory machinery condition monitoring under time-varying speed is usually amplitude-modulated (AM) and frequency-modulated (FM).
Yuexin Huang +4 more
doaj +1 more source
A Fast Signal-Dependent Time-Frequency Representation [PDF]
, 1996 In last few years, in order to overcome same limitations of the short time Fourier transform (STFT), while avoiding the cross-terms that make the Wigner distribution difficult to interpret, some signal-dependent time-frequency representations (SDTFR ...
Chan, FHY, Lam, FK, Lin, YM
core +1 more source
Open Geosciences, 2020 The reported occurrence of Albian- and Cenomanian-aged braided fluvio-deltaic channels in the Orange Basin, South Africa, opens a window of exploration activities to characterize these channels as they are renowned to form some of the world’s giant oil ...
Samakinde Chris Adesola +2 more
doaj +1 more source
Performance evaluation of the Hilbert–Huang transform for respiratory sound analysis and its application to continuous adventitious sound characterization [PDF]
, 2016 © 2016. This manuscript version is made available under the CC-BY-NC-ND 4.0 license http://creativecommons.org/licenses/by-nc-nd/4.0/The use of the Hilbert–Huang transform in the analysis of biomedical signals has increased during the past few years, but
Fiz Fernández, José Antonio +2 more
core +2 more sources
A 275–425-GHz Tunerless Waveguide Receiver Based on AlN-Barrier SIS Technology [PDF]
, 2007 We report on a 275–425-GHz tunerless waveguide receiver with a 3.5–8-GHz IF. As the mixing element, we employ a high-current-density Nb–AlN–Nb superconducting–insulating– superconducting (SIS) tunnel junction.
Bumble, Bruce +9 more
core +1 more source
A Demodulation Model of Dynamic Low-Finesse Fabry-Perot Cavity Based on the Instantaneous Frequency
IEEE Access, 2020 If the measurand changes during the spectrum acquisition process, it easily leads to the failure of the classic demodulation algorithms of low-finesse optical fiber Fabry-Perot (FP) sensors. To address this problem, a novel demodulation model is proposed
Wei Zhang +4 more
doaj +1 more source
IEEE Open Journal of Instrumentation and MeasurementIn vibration-based condition monitoring (VBCM) of rotating machinery, bearing defects typically induce amplitude and frequency modulations, making joint instantaneous amplitude–frequency analysis effective for distinguishing healthy from abnormal ...
Sulaiman Aburakhia +3 more
doaj +1 more source
Method of estimation of frequency variation relying on estimation of shift of spectral peaks
Системный анализ и прикладная информатика, 2021 Problem of estimation of variated frequency of components of polyharmonic signals has been arose. Three-dimensional time-frequency representation of signals is usually used to resolve this problem.
D. A. Kechik +2 more
doaj +1 more source