A target-field method to design circular biplanar coils for asymmetric shim and gradient fields

Author

Forbes, Larry K. ; Brideson, Michael A. ; Crozier, Stuart

Author_Institution

Sch. of Math. & Phys., Tasmania Univ., Hobart, Tas., Australia

Volume

41

Issue

6

fYear

2005

fDate

6/1/2005 12:00:00 AM

Firstpage

2134

Lastpage

2144

Abstract

The paper presents a method for designing circular, shielded biplanar coils that can generate any desired field. A particular feature of these coils is that the target field may be located asymmetrically within the coil. A transverse component of the magnetic field produced by the coil is made to match a prescribed target field over the surfaces of two concentric spheres (the diameter of spherical volume) that define the target field location. The paper shows winding patterns and fields for several gradient and shim coils. It examines the effect that the finite coil size has on the winding patterns, using a Fourier-transform calculation for comparison.

Keywords

Fourier transforms; coils; computational electromagnetics; electromagnetic fields; electromagnets; windings; Biot-Savart law; Fourier-transform calculation; asymmetric gradient fields; asymmetric shim fields; circular biplanar coils; circular shielded biplanar coils; target-field method; transverse magnetic field component; winding patterns; Australia; Current density; Design methodology; Integral equations; Magnetic field measurement; Magnetic fields; Magnetic resonance imaging; Protons; Radio frequency; Superconducting coils; Biot–Savart law; circular biplanar coils; integral equation; target field; winding patterns;

fLanguage

English

Journal_Title

Magnetics, IEEE Transactions on

Publisher

ieee

ISSN

0018-9464

Type

jour

DOI

10.1109/TMAG.2005.847638

Filename

1438454