MRI demodulation frequency changes provide different information
نویسندگان
چکیده
منابع مشابه
Probabilistic amplitude and frequency demodulation
A number of recent scientific and engineering problems require signals to be decomposed into a product of a slowly varying positive envelope and a quickly varying carrier whose instantaneous frequency also varies slowly over time. Although signal processing provides algorithms for so-called amplitudeand frequencydemodulation (AFD), there are well known problems with all of the existing methods....
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متن کاملSupplementary material: Probabilistic amplitude and frequency demodulation
t=1 exp (k1 cos(θt − θt−1) + k2 cos(θt − θt−2)) , (2) p(yt|at, θt) = Norm(yt; at cos(θt + ω̄t), σ 2 y). (3) The joint distribution over the amplitudes is a multivariate truncated Gaussian. Therefore, when the von Mises process becomes an independent, uniform distribution (k1 = 0 and k2 = 0), the model reduces to that of Sell and Slaney with a particular spectral weighting function determined by ...
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ژورنال
عنوان ژورنال: Magnetic Resonance in Medicine
سال: 2011
ISSN: 0740-3194
DOI: 10.1002/mrm.23099