Journal of Biomedical Engineering Research (대한의용생체공학회:의공학회지)

The Korean Society of Medical and Biological Engineering (대한의용생체공학회)
권호 표지
DOI QR코드

DOI QR Code

Development and Implementation of Noise-Canceling Technology for Digital Stethoscope

디지털 청진기를 위한 잡음 제거 기술 개발 및 구현

  • 이근상 (연세대학교 컴퓨터정보통신공학부) ;
  • 지유나 (연세대학교 컴퓨터정보통신공학부) ;
  • 전영택 ((주) 시그젠) ;
  • 박영철 (연세대학교 컴퓨터정보통신공학부)
  • Received : 2013.09.24
  • Accepted : 2013.11.07
  • Published : 2013.12.31
Download PDF
⟨ Previous Next ⟩

Abstract

In this paper, an algorithm for suppressing acoustic noises contained in stethoscope sound is proposed and implemented in real-time using an embedded DSP system. Sound collected by stethoscope is down-sampled and band-pass filtered, and later an NLMS adaptive filter is used to cancel the acoustic noise induced from external noise sources. Also, the unpredictable impulsive noises due to fabric friction and instantaneous tapping are detected using the SD-ROM algorithm, and suppressed using an algorithm approximating the morphology filter. The proposed algorithm was tested using signals collected with a digital stethoscope mockup, and implemented on an ARM920T-based DSP system.

Keywords

References

  1. M.L. Rice and D.J. Doyle, "Comparison of phonocardiographic monitoring location," in Proc. 17th Annual Conference of the IEEE Engineering in Medicine and Biology Society, Montreal, Canada, Sept. 1995, pp. 685-686.
  2. P. Varady, "Wavelet-based adative denoisiong of phonocardiograpic records," in Proc. 23rd Annual International Conference of the IEEE Engineering in Medicine and Biology Society, Istanbul, Turkey, Oct. 2001, pp. 1846-1849.
  3. M.C. Grenier, K. Gagnon, J. Genest Jr., J. Durand, and L.G. Durand, "Clinical comparison of acoustic and electronic stethoscopes and design of a new electronic stethoscope," American Journal of Cardiology, vol. 81, issue. 5, pp. 653-656, 1998. https://doi.org/10.1016/S0002-9149(97)00977-6
  4. Y.W. Bai and C.L. Lu, "The Embedded digital stethoscope uses the adaptive noise cancellation filter and the the Type 1 Chebyshev IIR bandpass filter to reduce the noise of the heart sound," in Proc. 7th Interantional Workshop on Enterprise Networking and Computing in Healthcare Industry, Busan, Korea, June 2005, pp. 278-281.
  5. N. Jatupaiboon, S. Pan-ngum and P. Israsena, "Electronic stethoscope prototype with adaptive noise cancellation," in Proc. 8th International Conference on ICT and Knowledge Engineering, Bangkok, Thailand, Nov. 2010, pp. 32-36.
  6. S. Haykin, Adaptive Filter Theory, Prentice Hall, 4 edition, 2001, pp. 334-340.
  7. E. Abreu and S. K. Mitra, "A signal-dependent rank ordered mean (SD-ROM) filter-a new approach for removal of impulses from highly corrupted images," in Proc. IEEE International Conference Acoustic, Speech, Signal Processing, Detroit, USA, May 1995, pp. 2371-2374.
  8. C. Chandra, M.S. Moore and S.K. Mitra, "An efficient method for the removal of impulse noise from speech and audio signals," in Proc. IEEE International Symposium on Circuits and System, Monterey, USA, Jun. 1998, pp. 206-208.
  9. J.C. Chien, M.C. Huang, Y.D. Lin and F.C. Chong, "A study of heart sound and lung sound separation by independent component analysis technique," in Proc. 28th Annual International Conference of the IEEE Engineering in Medicine and Biology Society, New York, USA Sept. 2006. pp. 5708-5711,
  10. C-H.H. Chu and E.J. Delp, "Impulsive noise suppression and background normalization of electrocardiogram signals using morphological operators," IEEE Transactions on Biomedical Engineering, vol. 36, no. 2, pp. 262-273, 1989. https://doi.org/10.1109/10.16474
  11. F. Zhang and Y. Lian, "QRS Detection based on multi-scale mathematical morphology for wearable ECG devices in body area networks," IEEE Transactions on Biomedical Circuits and Systems, vol. 3, no. 4, pp. 220-228, 2009. https://doi.org/10.1109/TBCAS.2009.2020093