OPTIMIZATION OF NMR RECEIVER BANDWIDTH BY INDUCTIVE COUPLING

被引：40

作者：

RAAD, A

DARRASSE, L

机构：

[1] Université de PARIS-SUD, Institut d'Electronique Fondamentale, CNRS UA 22, 91405 Orsay, bât

来源：

MAGNETIC RESONANCE IMAGING | 1992年 / 10卷 / 01期

关键词：

NMR COIL; INDUCTIVE COUPLING; RECEIVER BANDWIDTH; SIGNAL-TO-NOISE RATIO; FAST MRI; LOW-FIELD MRI;

D O I：

10.1016/0730-725X(92)90373-8

中图分类号：

R8 [特种医学]; R445 [影像诊断学];

学科分类号：

1002 ; 100207 ; 1009 ;

摘要：

We show, by theory and experiment, that inductive coupling can be used in overcoupled mode to widen the bandwidth of a high-Q NMR coil with only a negligible degradation of signal-to-noise ratio over the bandwidth of interest. The receiver bandwidth depends on the coupling coefficient between the NMR coil and the coupling coil rather than on the quality factor of the NMR coil alone. The overall bandwidth can be optimized by a judicious choice of the coupling coefficient. Moreover, this method permits wireless reception without the need for returning and rematching despite changes of NMR coils or samples. This technique has been incorporated in a 0.1-T imager for clinical routine. It achieves a typical bandwidth five times greater than that using a classic 50-OMEGA matching method.

引用

页码：55 / 65

页数：11

共 17 条

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