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Author Garachtchenko, Alexander ♦ Matlashov, Andrei ♦ Kraus, Robert H.
Source CiteSeerX
Content type Text
File Format PDF
Subject Domain (in DDC) Computer science, information & general works ♦ Data processing & computer science
Subject Keyword Squid Gradiometers ♦ Baseline Distance Optimization ♦ Second Order Gradiometers ♦ Optimal Baseline ♦ Noise Source ♦ Nearby Biomagnetic Source ♦ Optimization Criterion ♦ Primary Source ♦ Gradiometer Balance ♦ External Ambient Noise Result ♦ Baseline Length ♦ Ambient Noise ♦ Signal-to-noise Ratio ♦ Distant Dipolar Source ♦ Simulated Unshielded Environment ♦ Ambient Magnetic Noise ♦ Various Simulated Situation ♦ Complex Dependence ♦ Weak Magnetic Field ♦ Computer Simulation ♦ Present Optimal Gradiometer Baseline Length ♦ Shielded Case ♦ Squidbased Symmetric Axial Gradiometers ♦ Numerous Origin ♦ Distant Source
Abstract We optimized the baseline length of SQUIDbased symmetric axial gradiometers using a computer simulation. The signal-to-noise ratio (SNR) was used as the optimization criteria. We found that in most cases the optimal baseline is not equal to the depth of the primary source, rather it has a more complex dependence on the gradiometer balance and the ambient magnetic noise. We studied both first and second order gradiometers in simulated shielded environments and second order gradiometers in a simulated unshielded environment. The noise source was simulated as a distant dipolar source for the shielded case. We present optimal gradiometer baseline lengths for the various simulated situations. I. INTRODUCTION The measurement of weak magnetic fields generated by nearby biomagnetic sources is affected by ambient noise from distant sources both internal and external to the subject under study. External ambient noise results from sources with numerous origins, many of which are unpredictable i...
Educational Role Student ♦ Teacher
Age Range above 22 year
Educational Use Research
Education Level UG and PG ♦ Career/Technical Study