A Radio Frequency Pulse Generator for Magnetic Resonance Imaging Based on FPGA and DDS

doi:10.11938/cjmr20160408

Abstract

Abstract: A radio frequency (RF) pulse generator for magnetic resonance imaging (MRI) was designed based on field programmable gate array (FPGA) and direct digital synthesis (DDS). The generator utilizes FPGA to achieve DDS and embed soft pulse waveform (RAM), multiplier and related control logic. The RF generator showed high technical specifications, with frequency, phase and amplitude resolution up to 32 bits, 16 bits and 16 bits, respectively. Time precision of the soft pulse waveform reached 0.1 μs. FPGA provided a programmable interface, facilitating the control from sequence controller and generation of RF pulses. The feasibility of the design was demonstrated with imaging experiments.

Key words: MRI, field programmable gate array(FPGA), direct digital synthesis(DDS), radio frequency pulse generator

CLC Number:

O482.53

LI Yu-wei, XIAO Liang. A Radio Frequency Pulse Generator for Magnetic Resonance Imaging Based on FPGA and DDS[J]. Chinese Journal of Magnetic Resonance, 2016, 33(4): 590-596.

References

[1] Shen J, Xu Q, Liu Y, et al. Home-built magnetic resonance imaging system (0.3 T) with a complete digital spectrometer[J]. Rev Sci Instrum, 2005, 76(10):105101.
[2] Liu Min(刘敏), Qiu Wen-qi(邱雯绮), Sun Hui-jun(孙惠军), et al. Progress in the portable NMR spectrometer(便携式核磁共振谱仪的研究进展)[J]. Chinese J Magn Reson(波谱学杂志), 2014, 31(4):504-514.
[3] Chen Nan(陈楠), Chen Jie-hua(陈杰华), Hu Peng(胡鹏), et al. A digital transmitter for NMR based on FPGA(基于FPGA的核磁共振数字化发射机)[J]. Chinese J Magn Reson(波谱学杂志), 2008, 25(2):243-249.
[4] Xiao L, Sun B H, Ma Y P, et al. A digital magnetic resonance imaging spectrometer using digital signal processor and field programmable gate array[J]. Rev Sci Instrum, 2013, 84(5):054702.
[5] Ning Rui-peng(宁瑞鹏), Liu Yang(刘燕), Ren Jie-jing(任洁静), et al. Phase coherence between RF transmitter and receiver in digital MRI spectrometer(磁共振成像数字谱仪的射频发射/接收通道相位相干性的研究)[J]. Chinese J Magn Reson(波谱学杂志), 2007, 24(4):439-445.
[6] Mao Wen-ping(毛文平), Li Yun-yan(李云燕), Liu Zao(刘造), et al. A transmitter capable of fast modulation for NMR spectrometer-design and implementation(具有快速调制功能NMR发射机的设计与实现)[J]. Chinese J Magn Reson(波谱学杂志), 2013, 30(1):13-20.
[7] Ning R P, Yang G, Li G Y. A versatile pulse programmer for magnetic resonance imaging[J]. Rev Sci Instrum, 2011, 82(5):054301.
[8] Mao W P, Bao Q J, Yang L, et al. A modularized pulse programmer for NMR spectroscopy[J]. Meas Sci Technol, 2011, 22(2):620-626.
[9] Core S. Pulse Blaster DDS^TM Model DDS-Ⅱ-300 USB Owner's Manual[M]. Florida:Spin Core Technologies InC, 2009.
[10] Liu Hai-dan(刘海丹), Wang Hui-wang(王恢旺), Zhu Tian-xiong(朱天雄), et al. A frequency synthesizer for high-field NMR spectrometers(高场核磁共振波谱仪频率合成器设计)[J]. Chinese J Magn Reson(波谱学杂志), 2014, 31(1):91-99.
[11] Jiang Yu(蒋瑜), Shen Jian-hua(沈建华), Jiang Yun(蒋赟), et al. Application of the four DDS devices running in parallel to NMR(四路并行DDS合成技术在核磁共振中的应用)[J]. Chinese J Magn Reson(波谱学杂志), 2000, 17(6):483-487.
[12] Jiang Yun(蒋赟), Jiang Yu(蒋瑜), Tao Hong-yan(陶红艳), et al. DDS frequency source in NMR(用于核磁共振的直接数字合成频率源)[J]. Chinese J Magn Reson(波谱学杂志), 2001, 18(4):291-295.
[13] Ning Rui-peng(宁瑞鹏), Xu Qin(徐勤), Shen Jie(沈杰), et al. A PCI based complete digital frequency source for nuclear magnetic resonance spectrometer(基于PCI总线的全功能数字化频率源)[J]. Chinese J Magn Reson(波谱学杂志), 2006, 23(2):209-215.
[14] Xu Q, Christopher G, Zhou L, et al. An inexpensive and programmable RF transmitter setup for two-coil CASL[J]. Concept Magn Reson B, 2008, 33B(4):228-235.
[15] Xiao L, Wang W M. A radio-frequency source using direct digital synthesis and field programmable gate array for nuclear magnetic resonance[J]. Rev Sci Instrum, 2009, 80(12):124703.
[16] Bai Ju-xian(白居宪). Direct Digital Frequency Synthesis(直接数字频率合成)[M]. Xi'an(西安):Xi An Jiao Tong University Press(西安交通大学出版社), 2007.