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NMR shim coil design utilising a rapid spherical harmonic calculation method

Published online by Cambridge University Press:  17 February 2009

C. J. Snape-Jenkinson ,
S. Crozier  and
L. K. Forbes
C. J. Snape-Jenkinson
Affiliation:
Department of Mathematics, University of Queensland, St Lucia, Queensland 4072, Australia.
S. Crozier
Affiliation:
Centre for Magnetic Resonance, University of Queensland, St Lucia, Queensland 4072, Australia.
L. K. Forbes
Affiliation:
School of Mathematics and Physics, University of Tasmania, Hobart, Tasmania 7001, Australia.
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Abstract

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A rapid spherical harmonic calculation method is used for the design of Nuclear Magnetic Resonance shim coils. The aim is to design each shim such that it generates a field described purely by a single spherical harmonic. By applying simulated annealing techniques, coil arrangements are produced through the optimal positioning of current-carrying circular arc conductors of rectangular cross-section. This involves minimizing the undesirable harmonics in relation to a target harmonic. The design method is flexible enough to be applied for the production of coil arrangements that generate fields consisting significantly of either zonal or tesseral harmonics. Results are presented for several coil designs which generate tesseral harmonics of degree one.

Type
Research Article
Information
The ANZIAM Journal , Volume 43 , Issue 3 , January 2002 , pp. 375 - 386
Copyright
Copyright © Australian Mathematical Society 2002

References

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