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Instantaneous frequency spectra
The Leading Edge, 2015Abstract The goal of performing spectral decomposition is to determine the frequency spectra of the seismic signal as a function of traveltime. In conventional short-window Fourier methods and in continuous-wavelet transforms, there is a trade-off between temporal resolution and frequency resolution.
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Instantaneous frequency: Reply
The Leading Edge, 1992Phasors or formulas? In this article, I used a phasor representation to indicate why the instantaneous frequency of a seismic trace can be negative and why it can be unstable when the amplitude envelope is small. The equivalent algebraic representation of the analytic signal is well known and some may prefer it, but I considered that phasors gave the ...
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Definition of instantaneous frequency and frequency measurability
American Journal of Physics, 1975It is pointed out that the definitions of instantaneous and Fourier frequencies of a signal are noncausal and their measurement requires physically unrealizable systems. Some additional definitions of frequency are given that are causal.
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Nonparametric estimation of instantaneous frequency
IEEE Transactions on Information Theory, 1997Summary: The local polynomial approximation of time-varying phase is used in order to estimate the instantaneous frequency and its derivatives for a complex-valued harmonic signal given by discrete-time observations with a noise. The considered estimators are high-order nonparametric generalizations of the short-time Fourier transform and the Wigner ...
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On the instantaneous frequency of cyclostationary random signal
IEEE Transactions on Signal Processing, 1991Expressions are derived for the moments of instantaneous frequency of a cyclostationary random signal. It is shown that the cyclostationary signal is not only characterized by the periodicity of its statistical moments, but can also be characterized by the periodicity of the moments of its instantaneous frequency.
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The Journal of the Acoustical Society of America, 1999
Instantaneous frequency (IF) is an important signal characteristic arising in many fields. It is a concept intimately linked to time–frequency analysis, where it can be obtained from a time–frequency distribution (TFD) as the first conditional moment in frequency, suggesting that the IF is the average frequency at each time.
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Instantaneous frequency (IF) is an important signal characteristic arising in many fields. It is a concept intimately linked to time–frequency analysis, where it can be obtained from a time–frequency distribution (TFD) as the first conditional moment in frequency, suggesting that the IF is the average frequency at each time.
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A generalized stochastic resonance based instantaneous frequency estimation method under low SNR
Mechanical Systems and Signal Processing, 2022Zhenhua Xiong
exaly
An instantaneous frequency and group delay based feature for classifying EEG signals
Biomedical Signal Processing and Control, 2021Kwonhue Choi, Nabeel Ali Khan
exaly
Synchrosqueezing-Based Recovery of Instantaneous Frequency from Nonuniform Samples
SIAM Journal on Mathematical Analysis, 2011Hau-Tieng Wu
exaly