The Design of An Integrated Gradient Field/Frequency Lock Shim System for NMR Spectrometer

Abstract

Abstract:

The design of an integrated gradient-field/frequency lock-shim system for NMR spectrometer is presented. The integrated architecture is realized by combining embedded ethernet, field programmable gate array (FPGA), external memory interface (EMI), controller area network (CAN) bus and high-speed serial bus technologies, making the system compact and reliable. The system consists of three parts: (1) the field/frequency lock subsystem which ensures the stability of the magnetic field, (2) the shim subsystem which guarantees the consistency of the magnetic field, and (3) the gradient amplifier which generates the gradient field pulse. Due to its flexibility, the design can easily be adapted for different NMR spectrometers. The feasibility of the integrated system is illustrated by tests of the shim, lock and gradient outputs on a 11.7 T NMR spectrometer.

Key words: NMR, gradient, field/frequency lock, shim, integration

CLC Number:

O482.53

WANG Hui-Wang, LI Zheng-Gang, MAO Wen-Ping, BAO Qiang-Jia, LIU Zao, LIU Chao-Yang. The Design of An Integrated Gradient Field/Frequency Lock Shim System for NMR Spectrometer[J]. Chinese Journal of Magnetic Resonance, 2012, 29(4): 489-498.

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