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

作　　者：谷红芳 蔡文艳 魏玉科 刘政豪 王倩 王越 戴远东 马平 

机构地区：[1]Applied Superconductivity Research Center of Peking University [2]Department of Physics,State Key Laboratory for Artificial Microstructure and Mesoscopic Physics,Peking University,Beijing 100871,China

出　　处：《Chinese Physics B》2012年第4期185-192,共8页中国物理B（英文版）

基　　金：supported by the State Key Development Program for Basic Research of China (Grant Nos. 2006CB601007 and 2011CBA00106);the National Natural Science Foundation of China (Grant No. 10674006);the National High Technology Research and Development Program of China (Grant Nos. 2007AA03Z238 and 2007AA03Z213)

摘　　要：In order to eliminate the influence of the large-amplitude magnetic field noise that has complicated magnetocardio- graphic 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 fre- quency 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 thel 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.In order to eliminate the influence of the large-amplitude magnetic field noise that has complicated magnetocardio- graphic 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 fre- quency 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 thel 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.

关 键 词：electromagnetic interference leakage current subways MAGNETOCARDIOGRAPHY 

分 类 号：O441.5[理学—电磁学]