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Author Kannan, G. ♦ Milani, A.A. ♦ Panahi, I.M.S. ♦ Briggs, R.W.
Sponsorship IEEE Engineering in Medicine and Biology Society
Source IEEE Xplore Digital Library
Content type Text
Publisher Institute of Electrical and Electronics Engineers, Inc. (IEEE)
File Format PDF
Copyright Year ©1964
Language English
Subject Domain (in DDC) Technology ♦ Medicine & health ♦ Engineering & allied operations
Subject Keyword Acoustic noise ♦ Noise ♦ Adaptive filters ♦ Transfer functions ♦ Acoustic measurements ♦ Noise measurement ♦ Coils ♦ magnetic resonance imaging ♦ Active noise reduction ♦ acoustic noise
Abstract Functional magnetic resonance imaging (fMRI) acoustic noise exhibits an almost periodic nature (quasi-periodicity) due to the repetitive nature of currents in the gradient coils. Small changes occur in the waveform in consecutive periods due to the background noise and slow drifts in the electroacoustic transfer functions that map the gradient coil waveforms to the measured acoustic waveforms. The period depends on the number of slices per second, when echo planar imaging (EPI) sequencing is used. Linear predictability of fMRI acoustic noise has a direct effect on the performance of active noise control (ANC) systems targeted to cancel the acoustic noise. It is shown that by incorporating some samples from the previous period, very high linear prediction accuracy can be reached with a very low order predictor. This has direct implications on feedback ANC systems since their performance is governed by the predictability of the acoustic noise to be cancelled. The low complexity linear prediction of fMRI acoustic noise developed in this paper is used to derive an effective and low-cost feedback ANC system.
Description Author affiliation :: Univ. of Texas Southwestern Med. Center, Dallas, TX, USA
Author affiliation :: Univ. of Texas at Dallas, Richardson, TX, USA
ISSN 00189294
Education Level UG and PG
Learning Resource Type Article
Publisher Date 2011-12-01
Publisher Place U.S.A.
Rights Holder Institute of Electrical and Electronics Engineers, Inc. (IEEE)
Volume Number 58
Issue Number 12
Size (in Bytes) 856.54 kB
Page Count 7
Starting Page 3303
Ending Page 3309

Source: IEEE Xplore Digital Library