The rejection of magnetic noise from the wire using independent component analysis for magnetocardiogram

In magnetocardiogram (MCG) measurements, the magnetic noise from the wire used to suture the sternum after heart surgery becomes a problem. As one method of noise rejection, independent component analysis is effective. In this study, MCG measurements were carried out under the conditions that the wire was attached to a normal subject and that the wire was not attached. Signal processing by independent component analysis, digital high-pass filter and singer value decomposition analysis were carried out in order to reduce the effect of magnetic noise from the wire. From the comparison of the waveforms after this signal processing and the waveforms where the wire was not attached, it was apparent that the magnetic noise from the wire was reduced by independent component analysis. From this result, it is clear that independent component analysis is effective for the removal of the magnetic noise from the wire.