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Instantaneous frequency: Discussion

The Leading Edge, 1992
In Properties of instantaneous seismic attributes (July 1991 TLE), R.E. White shows graphically the instantaneous frequency can be negative. This property of the instantaneous frequency is very interesting, especially when we keep in mind the fact that an analytic signal associated with a real signal contains no negative-frequency components.
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Interpretation of Instantaneous Frequencies

American Journal of Physics, 1974
The relation between instantaneous frequencies and Fourier components of a time-dependent signal is examined. Examples are given in which large excursions of the instantaneous frequency do not correspond to any Fourier components, and in which Fourier components are not manifest in the instantaneous frequencies.
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Multiple motions from instantaneous frequency

Proceedings 1992 IEEE Computer Society Conference on Computer Vision and Pattern Recognition, 2003
The measurement of multiple velocities using phase-based methods is discussed. In particular, phase gradients (instantaneous frequency) from different bandpass channels (quadrature filter outputs) are used to estimate multiple image velocities in a single neighborhood. The approach is similar to that of M. Shizawa and K.
Keith Langley, David J. Fleet, Tim J. Atherton   +2 more
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Instantaneous frequency measurement

Medical Electronics & Biological Engineering, 1963
A 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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Instantaneous frequency spectra

The Leading Edge, 2015
Abstract 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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Comments on instantaneous frequency

SEG Technical Program Expanded Abstracts 1991, 1991
Instantaneous 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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Speaker Identification Using Instantaneous Frequencies

IEEE Transactions on Audio, Speech, and Language Processing, 2008
This paper presents an experimental evaluation of different features for use in speaker identification. The features are tested using speech data provided by the chains corpus, in a closed-set speaker identification task. The main objective of the paper is to present a novel parametrization of speech that is based on the AM-FM representation of the ...
Marco Grimaldi, Fred Cummins
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Algorithmic Measurement of Digital Instantaneous Frequency

IEEE Transactions on Communications, 1976
This paper presents an algorithmic method for measuring the instantaneous frequency of a uniformly sampled FM signal. The measured parameter, termed digital instantaneous frequency, is defined in a manner similar to that used to describe frequency-modulated, continuous-time signals.
Hussein S. El-Ghoroury, Someshwar C. Gupta   +1 more
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Instantaneous frequency: Reply

The Leading Edge, 1992
Phasors 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, 1975
It 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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