Effective position of reference microphone of active noise control for acoustic noise of magnetic resonance imaging

Kenji Muto, Ryosuke Osada, Kazuo Yagi

Research output: Chapter in Book/Report/Conference proceedingConference contribution

1 Citation (Scopus)

Abstract

Acoustic noise produced by magnetic resonance imaging (MRI) is over 100 dB. Ear protectors, such as earmuffs or earplugs, are insufficient for reducing the subjects' discomfort. The reference microphone position is the outside of the ear pad in case of general active noise control (ANC) headphones. We propose an effective position for the reference microphone for ANC for the subjects undergoing lower limb examination via MRI device. The MRI noise source is shown to be near the center in the hole of the MRI device. Here, we discuss the effect of the reference microphone position in ANC of the feedforward-type filtered-x normalized LMS algorithm. The normalization of the input signal is needed because this signal comprises unsteady pulsed MRI noise. The noise was simulated in a laboratory with the reverberation to evaluate the effects of the proposed method. The simulated result showed that controlling the sound-source position is more effective than the controlling the conventional ANC headphone position. The experiment showed that the proposed setup reduced the noise level by 3 dB more than that of the conventional one, just as predicted by computer simulation.

Original languageEnglish
Title of host publicationProceedings of the INTER-NOISE 2016 - 45th International Congress and Exposition on Noise Control Engineering: Towards a Quieter Future
PublisherGerman Acoustical Society (DEGA)
Pages73-78
Number of pages6
Publication statusPublished - 2016 Aug 21
Event45th International Congress and Exposition on Noise Control Engineering: Towards a Quieter Future, INTER-NOISE 2016 - Hamburg, Germany
Duration: 2016 Aug 212016 Aug 24

Other

Other45th International Congress and Exposition on Noise Control Engineering: Towards a Quieter Future, INTER-NOISE 2016
CountryGermany
CityHamburg
Period16/8/2116/8/24

Fingerprint

microphones
magnetic resonance
acoustics
ear protectors
reverberation
ear
limbs
examination
computerized simulation

Keywords

  • Hearing protection
  • MRI acoustical noise
  • Reference microphone

ASJC Scopus subject areas

  • Acoustics and Ultrasonics

Cite this

Muto, K., Osada, R., & Yagi, K. (2016). Effective position of reference microphone of active noise control for acoustic noise of magnetic resonance imaging. In Proceedings of the INTER-NOISE 2016 - 45th International Congress and Exposition on Noise Control Engineering: Towards a Quieter Future (pp. 73-78). German Acoustical Society (DEGA).

Effective position of reference microphone of active noise control for acoustic noise of magnetic resonance imaging. / Muto, Kenji; Osada, Ryosuke; Yagi, Kazuo.

Proceedings of the INTER-NOISE 2016 - 45th International Congress and Exposition on Noise Control Engineering: Towards a Quieter Future. German Acoustical Society (DEGA), 2016. p. 73-78.

Research output: Chapter in Book/Report/Conference proceedingConference contribution

Muto, K, Osada, R & Yagi, K 2016, Effective position of reference microphone of active noise control for acoustic noise of magnetic resonance imaging. in Proceedings of the INTER-NOISE 2016 - 45th International Congress and Exposition on Noise Control Engineering: Towards a Quieter Future. German Acoustical Society (DEGA), pp. 73-78, 45th International Congress and Exposition on Noise Control Engineering: Towards a Quieter Future, INTER-NOISE 2016, Hamburg, Germany, 16/8/21.
Muto K, Osada R, Yagi K. Effective position of reference microphone of active noise control for acoustic noise of magnetic resonance imaging. In Proceedings of the INTER-NOISE 2016 - 45th International Congress and Exposition on Noise Control Engineering: Towards a Quieter Future. German Acoustical Society (DEGA). 2016. p. 73-78
Muto, Kenji ; Osada, Ryosuke ; Yagi, Kazuo. / Effective position of reference microphone of active noise control for acoustic noise of magnetic resonance imaging. Proceedings of the INTER-NOISE 2016 - 45th International Congress and Exposition on Noise Control Engineering: Towards a Quieter Future. German Acoustical Society (DEGA), 2016. pp. 73-78
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