In magnetic resonance imaging (MRI), a gradient preemphasis module with more compensation channels and adjustable parameters is often desired for better imaging quality and faster imaging speed. With the conventional design, however, a high performance preemphasis module often requires high resource consumption such that the field programmable gate array (FPGA) may encounter huge resource overhead. In this study, a new gradient preemphasis implementation scheme based on time-division multiplexing was proposed. With the new design, an 11 channels×4 sets of parameters implementation could be achieved with only 1/44 of the resources required by the conventional scheme. To test the performance of the new implementation, eddy current curves and magnetic resonance images before and after preemphasis compensation were measured on a 0.35 T scanner and compared. The results demonstrated that the module could effectively reduce eddy currents and related artifacts on the images.
HUANG Zhao-hui
,
ZHANG Zhi
,
CHEN Li
,
CHEN Jun-fei
,
ZHANG Zhen
,
CHEN Fang
,
LIU Chao-yang
. A Time-Division Multiplexing Design for Gradient Preemphasis Module in Magnetic Resonance Imaging Scanner[J]. Chinese Journal of Magnetic Resonance, 2018
, 35(4)
: 465
-474
.
DOI: 10.11938/cjmr20182638
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