A Selection Method of Optimal Digital Low-pass Differentiator for Spike Detection of Surface Motor Unit Action Potential

표면 운동단위 활동전위 스파이크 검출을 위한 최적의 디지털 저역통과 미분기 선정 방법

  • 이진 (강원대학교 삼척캠퍼스 제어계측공학과) ;
  • 김성환 (서울시립대학교 전자전기컴퓨터공학부)
  • Received : 2011.06.28
  • Accepted : 2011.08.31
  • Published : 2011.10.01


The objective of this study is to analyze the performance of digital low-pass differentiators(LPD) and then to provide a method to select effective LPD filter, for detecting spikes of surface motor unit action potentials(MUAP). The successful spike detection of MUAPs is a first important step for EMG signal decomposition. The performances of simple and weighted LPD(SLPD and WLPD) filters are analyzed based on different filter lengths and varying MUAPs from simulated surface EMG signals. The SNR improving coefficient and effective MUAP duration range from the analysis results can be used to select proper LPD filters under the varying conditions of surface EMG.


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