Measurements, characteristics, and origin of new electromagnetic interference on magnetocardiographic measurements

Autor: Zhenghao Liu, Yuke Wei, Hongfang Gu, Yuandong Dai, Yue Wang, Wenyan Cai, Ping Ma, Qian Wang
Rok vydání: 2012
Předmět:
Zdroj: Chinese Physics B. 21:040702
ISSN: 1674-1056
DOI: 10.1088/1674-1056/21/4/040702
Popis: In order to eliminate the influence of the large-amplitude magnetic field noise that has complicated magnetocardiographic studies since October 2009, we have performed high-accuracy measurement of the environmental magnetic field noise in the vicinity of Beijing Subway Line 4 using a three-component height Tc radio frequency (rf) superconducting quantum interference device (SQUID). By analysing the spatial form and other characteristics of the time and the frequency domains and by calculating the circumferential magnetic field distribution based on a duel-end feeding system model, we reach the following conclusions: (i) the main source of magnetic field noise is the magnetic field generated by the subway trains, and (ii) the magnetic field interference results mainly from the imbalance between traction current and return rail current that is caused by the leakage current.
Databáze: OpenAIRE