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Biomag 96 pp 103–106Cite as

A Digital SQUID Controller for Unshielded Biomagnetic Measurements

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Abstract

A biomagnetometer capable of achieving low noise Performance without magnetic shielding would be attractive in a wide range of clinical and research applications. Magnetically shielded enclosures add significant initial cost to biomagnetometer systems and preclude their portability. The primary obstacle to unshielded operation is the immense dynamic range between the ambient magnetic noise and the SQUID noise floor. Ambient magnetic field noise found in a typical urban environment can be over eight Orders of magnitude greater than the sensitivity of a modern thin film low-Tc superconducting (LTS) dc-SQUID magnetometer [1]. Gradiometric magnetic sensors and linear combinations of magnetic sensors, including references may be used to separate the low-amplitude biomagnetic signals from the much larger environmental magnetic noise [2], [3]. The accurate reproduction of fields by these sensors is a prerequisite to the effectiveness of linear noise reduction methods.

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References

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Author information

Authors and Affiliations

  1. Department of Physics and Astronomy, The University of New Mexico, Albuquerque, NM, USA

    S. E. Robinson

Authors
  1. S. E. Robinson
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Editor information

Editors and Affiliations

  1. Radiology Service Albuquerque, VA Medical Center, Building 49, 114M 1501 San Pedro SE, Albuquerque, NM, 87108, USA

    Cheryl J. Aine

  2. Department of Physics, Dalhousie University, Halifax, Nova Scotia, Canada, B3H 3J5

    Gerhard Stroink

  3. Biophysics Group (P-21), MS D454, Los Alamos National Laboratory, P.O. Box 1663, Los Alamos, NM, 87545, USA

    Charles C. Wood

  4. Department of New Mexico School of Medicine, Albuquerque, NM, 87131, USA

    Yoshio Okada

  5. Department of Physics and Astronomy, The Open University, Milton Keynes, MK7 6AA, UK

    Stephen J. Swithenby

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© 2000 Springer Science+Business Media New York

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Robinson, S.E. (2000). A Digital SQUID Controller for Unshielded Biomagnetic Measurements. In: Aine, C.J., Stroink, G., Wood, C.C., Okada, Y., Swithenby, S.J. (eds) Biomag 96. Springer, New York, NY. https://doi.org/10.1007/978-1-4612-1260-7_26

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  • DOI: https://doi.org/10.1007/978-1-4612-1260-7_26

  • Publisher Name: Springer, New York, NY

  • Print ISBN: 978-1-4612-7066-9

  • Online ISBN: 978-1-4612-1260-7

  • eBook Packages: Springer Book Archive

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