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Noise-Robust Algorithm for PPG Signal Measurement

동잡음에 강건한 PPG 신호 측정 방안

  • Received : 2013.09.17
  • Accepted : 2013.12.04
  • Published : 2013.12.31

Abstract

In this paper, we propose a methods to eliminate PPG sensor noise resulted from user motion during measurement. Measured PPG signals require approperiate signal processing methods since various types of noises such as a motion noise by user movement and signal noises occurred from the change of measuring environments. This paper suggests a signal processing method that eliminates motion noises by measuring several PPG channels that are based on the stable patterns of the practical users. The PPG signals are measured by the two channels in this experiment. When the individual error rates are 20%, the proposed algorithm reduces the errors to 9.56%.

본 연구에서는 PPG 신호 측정에서 포함되는 잡음들 중에서 동잡음을 제거하는 신호처리 방안을 제안한다. 측정되는 PPG 신호는 측정 환경 자체의 신호 잡음과 사용자의 동작변화로 발생하는 동잡음 등 여러 잡음이 같이 존재하므로 적절한 신호처리 방법이 요구된다. 본 논문에서는 사용자의 안정된 상태에서 실제 PPG 신호를 측정한 뒤, 이 기준 신호를 바탕으로 여러 채널에서 측정한 다중화된 PPG 신호를 이용하여 동잡음을 제거하는 신호처리 방법을 제안한다. 본 논문의 실험에서는 두 개의 채널을 이용하여 PPG 신호를 측정하며, 각각 20%의 오류율을 가지는 신호를 본 논문에서 제안한 알고리즘으로 처리한 결과 9.56%로 오류율이 감소하였다.

Keywords

References

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