中国物理B ›› 2015, Vol. 24 ›› Issue (7): 78501-078501.doi: 10.1088/1674-1056/24/7/078501
• INTERDISCIPLINARY PHYSICS AND RELATED AREAS OF SCIENCE AND TECHNOLOGY • 上一篇 下一篇
邱阳a b c, 李华a b c, 张树林a b, 王永良a b, 孔祥燕a b, 张朝祥a b, 张永升a b, 徐小峰a b, 杨康a b c, 谢晓明a b
Qiu Yang (邱阳)a b c, Li Hua (李华)a b c, Zhang Shu-Lin (张树林)a b, Wang Yong-Liang (王永良)a b, Kong Xiang-Yan (孔祥燕)a b, Zhang Chao-Xiang (张朝祥)a b, Zhang Yong-Sheng (张永升)a b, Xu Xiao-Feng (徐小峰)a b, Yang Kang (杨康)a b c, Xie Xiao-Ming (谢晓明)a b
摘要: We constructed a 36-channel magnetocardiography (MCG) system based on low-Tc direct current (DC) superconducting quantum interference device (SQUID) magnetometers operated inside a magnetically shielded room (MSR). Weakly damped SQUID magnetometers with large Steward–McCumber parameter βc (βc ≈ 5), which could directly connect to the operational amplifier without any additional feedback circuit, were used to simplify the readout electronics. With a flux-to-voltage transfer coefficient ∂V/∂Ø larger than 420 μV/Ø0, the SQUID magnetometers had a white noise level of about 5.5 fT·Hz-1/2 when operated in MSR. 36 sensing magnetometers and 15 reference magnetometers were employed to realize software gradiometer configurations. The coverage area of the 36 sensing magnetometers is 210× 210 mm2. MCG measurements with a high signal-to-noise ratio of 40 dB were done successfully using the developed system.
中图分类号: (Superconducting quantum interference devices (SQUIDs))