摘要
目的针对目前高场磁共振成像系统中用来产生射频脉冲信号的频率源存在的问题,提出一种设计频率源的新方法。方法采用直接数字频率合成器件AD9910,可满足系统高频输出的需要,采用CPLD作为控制芯片,通过SPI方式控制,使所设计的电路具有简单高效的特点。结果实验结果表明,采用本设计方法可以产生频率、相位、幅度快速切换的高频信号。结论本设计方法为高场磁共振频率源设计提供了一个较好的解决方案。
Objective To propose an innovative method for the design of frequency source to solve the existing problem of current frequency sources that are used to produce radio frequency pulse signal in high-field magnetic resonance(MR)system.Methods The direct digital frequency synthesis device AD9910,which could meet the need of high frequency output in high-field MR system was used.CPLD was used as a control chip,which could plus the SPI bus,made the designed circuit much simpler and highly efficient.Results The results of experiments showed that high frequency signals can be produced using the proposed method,and the frequency,amplitude and phase of the output signals could all be switched instantly.Conclusion The design method in this paper provides a better solution for high-field MR frequency source design.
出处
《中国医学影像技术》
CSCD
北大核心
2010年第11期2184-2187,共4页
Chinese Journal of Medical Imaging Technology
基金
上海市重点学科建设项目(P0502)
关键词
磁共振成像
直接数字频率合成器
频率源
Magnetic resonance imaging
Direct digital frequency synthesis
Frequency source