Results 221 to 230 of about 1,527,120 (243)

Time-frequency distributions with complex argument

IEEE Transactions on Signal Processing, 2002
A distribution highly concentrated along the group delay or the instantaneous frequency (IF) is presented. It has been defined by introducing a signal with a complex argument in time-frequency (TF) analysis. Realization of a signal with a complex argument, using a signal with a real argument, is described.
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The generalized exponential time-frequency distribution

IEEE Transactions on Signal Processing, 1994
Time-frequency distributions (TFD) are joint time and frequency signal representations that, among other properties, maintain the true support of a signal's energy in both time and frequency. In addition to their mathematical elegance, TFDs can provide simultaneous resolution in time and frequency that exceeds that of the common spectrogram. In general,
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Instantaneous frequency and time-frequency distributions

1995 International Conference on Acoustics, Speech, and Signal Processing, 2002
It is generally stated that the conditional mean frequency of a time-frequency distribution (TFD) should equal the instantaneous frequency of the signal. The commonly accepted definition of instantaneous frequency as the derivative of the phase of the analytic signal sometimes leads to curious results.
Berkant Tacer, Patrick J. Loughlin
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Signal synthesis and positive time–frequency distributions

Journal of the Franklin Institute, 2000
zbMATH Open Web Interface contents unavailable due to conflicting licenses.
Syed Ismail Shah, Amro El-Jaroudi, Patrick J. Loughlin, Luis F. Chaparro   +3 more
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Multiple window spectrogram and time-frequency distributions

Proceedings of ICASSP '94. IEEE International Conference on Acoustics, Speech and Signal Processing, 2002
We extend the spectrum estimation method of Thomson (1982, 1990) to non-stationary signals by formulating a multiple window spectrogram. The traditional spectrogram can be represented as a member of Cohen's class of time-frequency distributions (TFDs) where the smoothing kernel is the Wigner distribution of the signal temporal window.
Frazer, G, Boashash, B
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Time-Frequency Distribution of Evoked Otoacoustic Emissions

British Journal of Audiology, 1997
Otoacoustic emissions (OAE) are non-stationary signals that vary in time depending on the characteristics of the stimulus. Traditional spectral analysis using Fourier methods ignores the effects of time and can miss important temporal information. Therefore, a better form of spectral analysis requires the use of time-frequency distribution methods ...
Ozdamar, O, Zhang, JW, Kalayci, T, Ulgen, Y   +3 more
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Decimated time-frequency distributions

Proceedings of IEEE-SP International Symposium on Time- Frequency and Time-Scale Analysis, 2002
The decimated generalized discrete time-frequency distribution (D-GDTFD) was introduced by O'Hair and Suter (see IEEE International Conference on Circuits and Systems, London, U.K., 30 May-2 June 1994). It trades bandwidth for speed of implementation and requires greatly reduced storage over the generalized discrete time-frequency distribution (GDTFD).
J.R. O'Hair, B.W. Suter
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Analysis of noise in time-frequency distributions

IEEE Signal Processing Letters, 2002
Exact expressions for the quadratic distributions' variance of signals corrupted with white stationary, white nonstationary, and colored stationary noise are derived. It has been shown that the signal-dependent part of variance is closely related to the nonnoisy distribution values.
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The marginals and time-frequency distributions

SPIE Proceedings, 2003
We address the question of the importance of satisfying the marginal conditions in a time-frequency distribution and discuss in detail the fundamental and practical issues involved. We also examine the marginals of the spectrogram. The spectrogram often gives reasonable results even though both marginals can never be satisfied exactly, but sometimes it
Leon Cohen, Patrick J. Loughlin
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On Wigner-based sparse time-frequency distributions

2015 IEEE 6th International Workshop on Computational Advances in Multi-Sensor Adaptive Processing (CAMSAP), 2015
Signals made of the superimposition of a reduced number of AM-FM components can be characterized by a time-frequency signature which consists of weighted trajectories in the plane, thus ending up with an ideal representation of their energy distribution that is intrinsically sparse.
Patrick Flandrin, Nelly Pustelnik, Pierre Borgnat   +2 more
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