New Strategy for Stopping Sifting Process during Biosignals De-nosing By EMD: In Case of Low FrequencyArtifact Reduction from ECG and EMG

Removal of artifacts from bio-signals is a necessary step before automaticprocessing and obtaining clinical information. Recently, many applications ofEmpirical Mode Decomposition (EMD) on biomedical researches have beenpresented that artifact reduction from bio-signals is one of them. EMD separates atime series into finite numbers of its individual oscillations, which are calledintrinsic mode function (IMF). The process of the IMF extraction from a signal isknown as the sifting process. The main issue during sifting process is to select anappropriate criterion for stopping IMF extraction when the process reaches theartifact components. In this paper, we try to investigate mean power frequency(MPF) for stopping sifting process, in case of low frequency artifact reduction fromECG and EMG signals. In order to evaluate effectiveness of the proposed indexduring sifting process, reduction of baseline noise from electrocardiogram signals(ECG) and ECG artifact from electromyogram signals (EMG) have beeninvestigated. The obtained results indicate MPF can be considered as an acceptablecriterion to stop sifting process during low frequency artifact elimination.

Keywords:

Artifact reduction , EMD , Sifting process , ECG , EMG , MPF