A MODULAR 31-CHANNEL SQUID SYSTEM FOR BIOMAGNETIC MEASUREMENTS

被引:10
作者
Doessel, O. [1 ]
David, B. [1 ]
Fuchs, M. [1 ]
Krueger, J. [1 ]
Luedeke, K. -M. [1 ]
Wischmann, H. -A. [1 ]
机构
[1] Philips GmbH Forschungslab, Forsch Abt Tech Syst Hamburg, Postfach 540840, D-2000 Hamburg 54, Germany
关键词
D O I
10.1109/77.233313
中图分类号
TM [电工技术]; TN [电子技术、通信技术];
学科分类号
0808 ; 0809 ;
摘要
Our modular multichannel SQUID-system, in which every single channel can be optimized or replaced individually, was further improved. The number of channels was increased to 31. The noise level is better than 10fT/root Hz. A new way of RF-shielding using conductive paint avoids degradation of the SQUID characteristics due to RF-interference without introducing significant extra noise, so that the system works without any Faraday cage. A simplified way of coupling the modulation and feedback signal directly to the SQUID was developed and tested successfully. The SQUID module with the superconducting connections to the gradiameter and its superconducting shield was miniaturized to an outer diameter of 5mm, so it can be placed near to the gradiometer without introducing significant unbalance. Tests have proven the accuracy of the system with respect to the localization of a single current dipole to be better than 2mm.
引用
收藏
页码:1883 / 1886
页数:4
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