Results 251 to 260 of about 436,878 (286)

Instantaneous frequency of multicomponent signals

IEEE Signal Processing Letters, 1999
The failure of the traditional definition of instantaneous frequency (IF/sub t/) in the multicomponent case has been often reported. We determine the reasons for the failure of this definition. This enables us to understand and integrate all previously reported cases in a simple unified theory.
P.M. Oliveira, V. Barroso
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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.
K. Langley, D.J. Fleet, T. Atherton
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Instantaneous VEP signal frequency analysis.

Biomedical sciences instrumentation, 1993
Various methods have been used in the analysis of visually evoked potential signals. Due to the high noise content of the ssVEP signal, the signal is usually filtered using averaging or an order statistic filter, and then analyzed for frequency content.
D, Shelton, H, Longbotham
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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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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 ...
M. Grimaldi, F. Cummins
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A Low Frequency Meter with Instantaneous Response

IEEE Transactions on Biomedical Engineering, 1979
A practical method is described for instantaneous frequency measurement by computation of the reciprocal of the time interval between two events. Use is made of inexpensive integrated circuits.
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Spectrographic measurement of instantaneous frequency and the time-dependent weighted average instantaneous frequency

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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Dispersive instantaneous frequency imaging

Journal of Sound and Vibration, 2023
Yanfeng Lang, Zhibo Yang, Xuefeng Chen
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Instantaneous Frequency-Measuring Receivers (Letters)

IEEE Transactions on Microwave Theory and Techniques, 1972
The instantaneous frequency-measuring receiver (IFR) is becoming widely known to microwaye systems engineers, but as a consequence of the defense applications its origins are obscure. The pioneering work on the phase-discriminator technique, which is the basis of most modern IFR systems, was done in the Mullard Research Laboratories, Red Hill, Surrey ...
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Instantaneous Frequency Measurement (IFM) Receivers

2005
In this chapter, the operating principles of IFM receivers, some trade-offs in the designs, and several schemes for digitizing the outputs of the video amplitude will be discussed. Since an IFM receiver can measure only one input signal at a time, one continuous-wave (CW) signal will block the receiver from measuring other input signals.
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