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.
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
.
DOI: 10.11938/cjmr20160408
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