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Instantaneous frequency measurement
Medical Electronics & Biological Engineering, 1963A method is outlined for obtaining an indication of instantaneous frequency by a computation of the reciprocal of the time for one period. This is accomplished by the discharge of a condenser through an element having current proportional to the square of the voltage. The square law element consists of a biased diode network.
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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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Comments on instantaneous frequency
SEG Technical Program Expanded Abstracts 1991, 1991Instantaneous frequency is defined, like angular velocity in rotational physics, as the derivative of the instantaneous phase (or angle). An alternative frequency measure is the change in instantaneous phase over a time interval divided by that time interval.
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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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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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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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Practical Instantaneous Frequency Analysis Experiments
2014This paper investigated the use of instantaneous frequency (IF) instead of power amplitude and power spectrum in side-channel analysis. By opposition to the constant frequency used in Fourier Transform, instantaneous frequency reflects local phase differences and allows detecting frequency variations.
Roman Korkikian +3 more
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An instantaneous frequency and group delay based feature for classifying EEG signals
Biomedical Signal Processing and Control, 2021Nabeel Ali Khan +2 more
exaly
A generalized stochastic resonance based instantaneous frequency estimation method under low SNR
Mechanical Systems and Signal Processing, 2022Zhenhua Xiong
exaly
Estimating and interpreting the instantaneous frequency of a signal. I. Fundamentals
Proceedings of the IEEE, 1992B Boashash
exaly