Journal of Biomedical Engineering Research (대한의용생체공학회:의공학회지)

The Korean Society of Medical and Biological Engineering (대한의용생체공학회)
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Background Noise Reduction by Software Methods in the 37-channel SQUID Magnetometer System

뇌자도 측정용 37채널 스퀴드 자력계에서의 합성 미분계 및 적응필터, 주파수영역 적응필터에 의한 배경잡음 제거

  • 김기웅 (한국표준과학연구원 초전도그룹) ;
  • 이용호 (한국표준과학연구원 초전도그룹) ;
  • 권혁찬 (한국표준과학연구원 초전도그룹) ;
  • 김진목 (한국표준과학연구원 초전도그룹) ;
  • 강찬석 (고려대학교 물리학과)
  • Published : 2003.06.01
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Abstract

Measuring subtle neuromagnetic signals requires eliminating background noises. Especially, a SQUID magnetometer is very sensitive to the magnetic noise even from a distant source. As typical software methods, we use the synthetic gradiometer of the adaptive filtering to reduce the noises. In this article, we present noise reduction effects in our 37-channel SQUID magnetometer system by applying each method including the frequency-domain adaptive filtering and discuss a selective application of the methods to the detection of clinical magnetoencephalogram signals.

스퀴드 자력계는 외부의 배경잡음원에 대해서 매우 민감하므로 뇌자도 신호 측정을 목적으로 하는 미세 자기신호 측정에서는 배경자기잡음을 충분히 제거해야 한다. 배경잡음 제거에 일반적으로 사용되는 소프트웨어적 방법으로는 합성 미분계 및 적응필터 방법이 있다. 본 논문에서는 뇌자도 측정용으로 개발한 37채널 스퀴드 자력계에서 합성 미분계 적응필터 및 주파수 영역 적응필터를 적용하여 각각의 배경잡음 제거 효과 및 각 방법의 장단점을 살펴보고, 임상 뇌자도 측정시 상기 방법들의 선택적 적용에 관하여 논의한다

Keywords

References

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