基于FPGA的低场核磁共振谱仪脉冲编程器设计与实现

波谱学杂志 ›› 2011, Vol. 28 ›› Issue (3): 317-325.

基于FPGA的低场核磁共振谱仪脉冲编程器设计与实现

谢庆明，肖立志^*，张晓玲，李晓楠

油气资源与探测国家重点实验室，中国石油大学(北京), 北京 102249

收稿日期:2011-03-31 修回日期:2011-04-19 出版日期:2011-09-05 发布日期:2011-09-05
通讯作者: 肖立志 E-mail:xiaolizhi@ cup.edu.cn；xieqingming.cup@ gmail.com
基金资助:
国家自然科学基金资助项目（41074102），科技部国际合作资助项目(2009DFA61030).

Design and Implementation of An FPGA-Based Pulse Programmer for Low Field NMR Spectrometer

XIE Qiang-Ming, XIAO Li-Zhi^*, ZHANG Xiao-Ling, LI Xiao-Nan

State Key Laboratory of Petroleum Resource and Prospecting, China University of Petroleum, Beijing 102249, China

Received:2011-03-31 Revised:2011-04-19 Online:2011-09-05 Published:2011-09-05
Contact: XIAO Li-Zhi E-mail:xiaolizhi@ cup.edu.cn；xieqingming.cup@ gmail.com
Supported by:
国家自然科学基金资助项目（41074102），科技部国际合作资助项目(2009DFA61030).

摘要/Abstract

摘要：

脉冲编程器在核磁共振(NMR) 谱仪中非常重要，具有产生脉冲序列所需的射频脉冲，控制回波信号的同步接收等功能. 基于FPGA的同步性能和时序控制功能，设计了低场NMR谱仪的脉冲编程器，可产生任意脉冲序列，实现脉冲频率、相位、幅度的灵活调节. 利用设计的脉冲编程器在0.540 Tesla均匀磁场下进行了CuSO₄溶液的T₁和T₂测量，得到高信噪比的NMR回波串.

关键词: 低场核磁共振(LF NMR), 脉冲编程器, FPGA, DDS

Abstract:

Pulse programmer is an integrating part of NMR spectrometer, which is used to generate RF pulse and to receive echo trains signals. Taking advantage of the synchronous performance and excellent timing control capacity of FPGA, a FPGA-based pulse programmer for low field NMR spectrometer was designed to generate pulse sequences for different NMR experiments. Flexible control of the frequency, phase and amplitude of the RF pulses could be achieved with this pulse programmer. Performance of the pulse programmer was evaluated with measurements of transverse and longitudinal relaxation rates of CuSO₄ solution under uniform magnetic field (0.540 Tesla). The pulse programmer was also used to collect echo trains signals with high signal-to-noise ratio.

Key words: low field nuclear magnetic resonance, pulse programmer, FPGA, DDS

中图分类号:

P631.83

谢庆明, 肖立志, 张晓玲, 李晓楠. 基于FPGA的低场核磁共振谱仪脉冲编程器设计与实现[J]. 波谱学杂志, 2011, 28(3): 317-325.

XIE Qiang-Ming, XIAO Li-Zhi, ZHANG Xiao-Ling, LI Xiao-Nan. Design and Implementation of An FPGA-Based Pulse Programmer for Low Field NMR Spectrometer[J]. Chinese Journal of Magnetic Resonance, 2011, 28(3): 317-325.

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