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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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Mutual relation between instantaneous frequency and instantaneous bandwidth

Proceedings of the Sixth International Symposium on Signal Processing and its Applications (Cat.No.01EX467), 2002
The concepts of instantaneous frequency (IF/sub t/) and instantaneous bandwidth (IB/sub t/) have traditionally been considered as independent spectral features. Previous work has suggested, however, that the spectral dynamics of the signal (and, hence, its IF/sub t/) may have an impact on IB/sub t/ and on the achievable spectral resolution. We consider
P.M. Oliveira, V. Barroso
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Superconductive digital instantaneous frequency measurement subsystem

IEEE Transactions on Microwave Theory and Techniques, 1993
A 5-b high-temperature-superconductive digital instantaneous frequency-measurement (DIFM) subsystem has been constructed for the determination of the frequency of unknown signals over a 500-MHz bandwidth, centered on 4 GHz, with a resolution of +or-7.8 MHz. The subsystem contains a cryogenic section with five discriminator modules using superconductive
G.-C. Liang, C.F. Shih, R.S. Withers, B.F. Cole, M.E. Johansson, L.P. Suppan   +5 more
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Circuit for measurement of instantaneous frequency

American Journal of Physiology-Heart and Circulatory Physiology, 1980
This paper describes a circuit that measures the instantaneous frequency of a pulse train applied to the input. Analog outputs are provided that are linearly proportional to the interval between successive pulses and to the reciprocal of that same interval.
R, McGillivray, R, Wald
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Instantaneous frequency measurement using double-frequency probing

SPIE Proceedings, 2013
This paper presents a new double-frequency method for the instantaneous frequency and amplitude measurement of unknown microwave signal. Using the specific interaction of double-frequency radiation and FBG (fiber Bragg grating) with a π phase shift allowed us to obtain measuring characteristics, that are independent of the energy fluctuations of the ...
Oleg G. Morozov, Anvar A. Talipov, Marat R. Nurgazizov, Tagir S. Sadeev, Andrey G. Fedorov   +4 more
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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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Frequency Relaying Based on Instantaneous Frequency Measurement

IEEE Power Engineering Review, 1996
A frequency relay capable of under/over frequency and rate of change of frequency measurements has been implemented on a digital signal processor using an instantaneous frequency measuring algorithm. Careful attention to the filtering aspects of the relay is needed under dynamic conditions due to frequency modulation of the input signal.
P. J. Moore, J. H. Allmeling, A. T. Johns   +2 more
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Time–frequency distribution spectral polynomials for instantanous frequency estimation

Signal Processing, 1999
zbMATH Open Web Interface contents unavailable due to conflicting licenses.
Wang, Chenshu., Amin, Moeness G.
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The calculation of instantaneous frequency and instantaneous bandwidth

GEOPHYSICS, 1992
A number of ways have been offered to calculate instantaneous frequency, an important complex seismic trace attribute. The standard calculation follows directly from its definition and requires two differentiations (Taner et al., 1979). By avoiding these differentiations, three formulas that approximate instantaneous frequency are faster to compute ...
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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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