Biomagnetic measurements are affected by environmental magnetic noises emitted by various electric systems including trains and elevators. In this study, we measured low-frequency magnetic noise by using a fluxgate magnetometer at a laboratory located in an urban area and analyzed the dominant noise sources during real-world operation of these systems. Additionally, we evaluated the noise reduction effect of a small, magnetically shielded box combined with compensation coils.
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2.
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3.
WooT., NagaseM., OhsakiH. and SekinoM., Development of a SQUID system for ultralow-field MRI measurement, IJAEM45 (2014), 771-778.
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YamazakiK., Environmental magnetic noise and magnetic shielding I: Fluctuation of magnetic fields due to electric railcar, JMSJ29 (2005), 405-415.
5.
YamazakiK., OnokiT., KobayashiK., MuramatsuK. and HagaA., Evaluation on shielding factor of active magnetic shielding for electron beam lithography system, JMSJ32 (2008), 386-391.
