Abstract:
:High-order radiofrequency transmitter coils are described that permit, in the context of NMR imaging, a knowledgeable trade-off between coil complexity and the degree of inhomogeneity over a specified volume of space. A mathematical formulation of high-order coils is developed for an axially symmetric polarizing dc field and transverse rf field. The field is created by a number of longitudinal current filaments with equal angular separations on the wall of a cylinder. In its most general form, each current can be independently specified. Circularly or linearly polarized fields can be created. Quadrature and saddleshaped coils emerge as special cases of the general formulation. The development has been tested experimentally and good agreement found. High-order coils can also be used as receivers, permitting more equal weighting of the sensitivities of each pixel.
journal_name
Magn Reson Medjournal_title
Magnetic resonance in medicineauthors
Sotgiu A,Hyde JSdoi
10.1002/mrm.1910030108subject
Has Abstractpub_date
1986-02-01 00:00:00pages
55-62issue
1eissn
0740-3194issn
1522-2594journal_volume
3pub_type
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更新日期:1999-05-01 00:00:00
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更新日期:2005-06-01 00:00:00
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