A system for biomagnetic measurement (MCG) with planar single-layer high-TC dc-SQUID gradiometers in unshielded environment

We prepared different types of planar single-layer high-T-C DC-SQUID gradiometers and magnetometers with bicrystal and step-edge Josephson junctions in order to develop a one-channel heart monitoring system, which shall be able to measure the MCG of a patient in an unshielded environment for clinical application. Our system was used for mapping the heart magnetic field of a patient in a shielded room in order to optimize the sensor position. We were also able to measure the R-peak of the QRS-complex in a realtime mode in unshielded environment without averaging [1]. The system was tested in a clinical environment and the obtained signals have been processed in different ways (e.g. with comb filters and peak trigger accumulation) resulting in medically relevant data.