Several approaches have been proposed for the solution of this problem but development is currently still very much in progress. Some of the more succesfull approaches are [Principal component analysis]? and [Independent component analysis]?.
One of the practical applications having cueued research in this area, is medical imaging of the brain with MRI. This kind of imaging involves careful measurements of magnetic fields outside the head which yields an accurate 3D-picture of the interior of the head. However, external sources of electromagnetic fields such as a wristwatch on the subjects arm, will significantly degrade the accuracy of the measurement. Applying source separation techniques on the measured signals can help removing undesired artefacts from the signal.
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