Discrete spatial filtering with SQUID gradiometers in biomagnetism

Journal Article · Tue Apr 01 00:00:00 EST 1986 · J. Appl. Phys.; (United States)

DOI:https://doi.org/10.1063/1.337008· OSTI ID:6123173

Bruno, A C; Costa Ribeiro, P; von der Weid, J P; Symko, O G

First-, second-, and third-order gradiometers used in detecting biomagnetic signals are analyzed as spatial filters. Their transfer functions independent of the source to be measured are presented and both the magnitude and phase characteristics of the transfer functions are analyzed. The distortion introduced by the gradiometer can be estimated from these characteristics. In order to treat the signal in that approach, the spatial Fourier transform of a magnetic signal produced by a current dipole at a given distance is discussed.

• Research Organization: Department of Physics, Pontificia Universidade Catolica, Rio de Janeiro, Brazil
• OSTI ID: 6123173
• Journal Information: J. Appl. Phys.; (United States), Vol. 59:7
• Country of Publication: United States
• Language: English

Related Subjects

71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
BIOLOGICAL MATERIALS
MAGNETIC FIELDS
MEASURING METHODS
SQUID DEVICES
DATA PROCESSING
TRANSFER FUNCTIONS
FILTERS
FOURIER TRANSFORMATION
ELECTRONIC EQUIPMENT
EQUIPMENT
FLUXMETERS
FUNCTIONS
INTEGRAL TRANSFORMATIONS
MATERIALS
MEASURING INSTRUMENTS
MICROWAVE EQUIPMENT
PROCESSING
SUPERCONDUCTING DEVICES
TRANSFORMATIONS
420201* - Engineering- Cryogenic Equipment & Devices