核磁共振波谱仪用射频功率放大器的设计与实现

波谱学杂志 ›› 2011, Vol. 28 ›› Issue (3): 326-338.

核磁共振波谱仪用射频功率放大器的设计与实现

李由^1,2，毛文平^1,2，王恢旺^1,2，刘洋¹, 陈方¹，刘朝阳^1*

1. 波谱与原子分子物理国家重点实验室，武汉磁共振中心（中国科学院武汉物理与数学研究所），湖北武汉 430071；2. 中国科学院研究生院，北京 100049

收稿日期:2011-04-06 修回日期:2011-04-26 出版日期:2011-09-05 发布日期:2011-09-05
基金资助:
国家自然科学基金资助项目（10675162），科技支撑计划资助项目（2006BAK03A22）.

Design and Implementation of An RF Power Amplifier Used in Nuclear Magnetic Resonance Spectrometer

LI You^1,2, MAO Wen-Ping^1,2, WANG Hui-Wang^1,2, LIU Yang¹, CHEN Fang¹, LIU Chao-Yang^1*

1. State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, Wuhan Center for Magnetic Resonance (Wuhan Institute of Physics and Mathematics, Chinese Academy of Sciences), Wuhan 430071, China; 2. Graduate School of the Chinese Academy of Sciences, Beijing 100049, China

Received:2011-04-06 Revised:2011-04-26 Online:2011-09-05 Published:2011-09-05
Supported by:
国家自然科学基金资助项目（10675162），科技支撑计划资助项目（2006BAK03A22）.

摘要/Abstract

摘要：

介绍了一种应用于核磁共振（Nuclear Magnetic Resonance，NMR）波谱仪的宽频带射频功率放大器的设计与实现，提出了射频功率放大器门控信号的设计，探讨了利用传输线变压器构建功率MOSFET输入输出阻抗匹配网络的方法. 该射频功率放大器采用多级驱动结合功率放大的结构，包含2个工作模块和基于宽频带定向耦合器的辅助电路，支持高带和宽带通道的相关实验. 将该射频功率放大器应用在自主研发的500 MHz高分辨率液体NMR谱仪上，测量射频功放的上升、下降时间及输出线性度，并对比测试¹H和¹³C NMR标样的信噪比，实验结果证明了该设计的可行性.

关键词: 核磁共振(NMR), 功率放大器, 传输线变压器, 匹配网络

Abstract:

The design and implementation of a broadband RF power amplifier used in nuclear magnetic resonance spectrometer were introduced. Based on a two-stage architecture, the power amplifier was composed of a high frequency module, a broadband module and two directional couplers, to meet various requirements of NMR experiments. The rise time, fall time and power linearity of the power amplifier was measured on a home-built 500 MHz NMR spectrometer. Comparison of NMR sensitivity demonstrated good performance of this power amplifier in common NMR experiments.

Key words: NMR, power amplifier, transmission line transformer, matching circuits

中图分类号:

O482.53

李由, 毛文平, 王恢旺, 刘洋, 陈方, 刘朝阳. 核磁共振波谱仪用射频功率放大器的设计与实现[J]. 波谱学杂志, 2011, 28(3): 326-338.

LI You, MAO Wen-Ping, WANG Hui-Wang, LIU Yang, CHEN Fang, LIU Chao-Yang. Design and Implementation of An RF Power Amplifier Used in Nuclear Magnetic Resonance Spectrometer[J]. Chinese Journal of Magnetic Resonance, 2011, 28(3): 326-338.

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