波谱学杂志 ›› 1999, Vol. 16 ›› Issue (4): 364-367.

• 研究论文 • 上一篇    下一篇

高场核磁共振的数字正交检波方法

谢海滨, 李鲠颖   

  1. 华东师范大学分析测试中心, 上海 200062
  • 收稿日期:1999-03-15 修回日期:1999-05-04 出版日期:1999-08-05 发布日期:2018-01-11
  • 作者简介:谢海滨,男,1969年出生,博士研究生
  • 基金资助:
    国家自然科学基金(批准号:19775015)和"霍英东基金"资助项目

DIGITAL QUADRATURE DETECTION IN HIGH FIELD NMR

Xie Haibin, Li Gengying   

  1. Analytical Center, East China Normal University, Shanghai 200062
  • Received:1999-03-15 Revised:1999-05-04 Online:1999-08-05 Published:2018-01-11

摘要: 在核磁共振中,常规的正交检测技术采用两路相敏检波.因为两路相检波的相位和幅度存在不平衡而引起谱失真,所以必须用相位循环来消除.这增加了实验时间.本文提出并在MSL-300 NMR谱仪上实现了一种数字正交检波方法.这种方法使用单路相检波,避免了两路不平衡而引起的谱线失真,因此不需要相位循环技术

关键词: 核磁共振, 数字正交检波

Abstract: In conventional NMR, quadrature detection of free induction decay signal employs two channels of phase sensitive detector. With this technique, phase cycling for canceling the spectral distortion due to unbalance between two channels is indispensable. This makes the experiment time longer than necessary when the signal-to-noise ratio is good enough to ensure one scan sampling. In order to overcome this problem, a digital quadrature detection technique is proposed and carried out on an MSL-300 spectrometer in the present article. The method utilizes only one channel of analog-to-digit conversion. Therefore, distortion caused by the unbalance between two channels can be fully avoided. As a result, no phase cycling for canceling the distortion mentioned above is necessary.

Key words: NMR, Digital quadrature detection