Signal Space Separation Method for a Biomagnetic Sensor Array Arranged on a Flat Plane for Magnetocardiographic Applications: A Computer Simulation Study
(a) An array of sensors and the coordinate system used in our computer simulation. The sensor array consists of 64 sensors arranged in an 8 × 8 configuration on the plane , called the sensor plane. The sensor array covers an area of 20 cm × 20 cm, and the sensors measure the z component of the magnetic field, which is the component normal to the sensor plane. The source space (,, ) is shown. (b) The source time course assumed for a source located at (−3 cm, 0 cm, and 2 cm). (c) The signal sensor data are shown in the upper panel, and the signal plus sensor-noise data are shown in the lower panel. Here, sensor noise was added to the signal data with the signal-to-noise ratio (SNR) of 10. The sensor time courses are normalized to the maximum value in each panel, and the ordinate indicates the normalized values.