基于单片FPGA的磁共振成像梯度计算模块

波谱学杂志 ›› 2010, Vol. 27 ›› Issue (2): 163-171.

基于单片FPGA的磁共振成像梯度计算模块

肖亮, 汤伟男, 王为民

北京大学电子系，信息科学技术学院量子电子研究所，北京 100871

收稿日期:2009-11-09 修回日期:2009-12-26 出版日期:2010-06-05 发布日期:2010-06-05
基金资助:
科技部资助项目(2008ZX05008-004-015).

An FPGA-Based Single-Chip Gradient Calculation Module for Magnetic Resonance Imaging

XIAO Liang, TANG Wei-Nan, WANG Wei-Min

Institute of Quantum and Electronics, School of Electronics Engineering & Computer Science, Peking University, Beijing 100871, China

Received:2009-11-09 Revised:2009-12-26 Online:2010-06-05 Published:2010-06-05
Supported by:
科技部资助项目(2008ZX05008-004-015).

摘要/Abstract

摘要：

提出了一种用于磁共振成像的高集成度的数字梯度计算模块. 它可以实时计算任意层面成像所需的梯度波形，并能对X、Y、Z三个通道做波形预增强处理. 该模块基于单片FPGA器件，梯度波形数据预存于FPGA内嵌的RAM中，波形更新时间最小为1 μs. 在FPGA内部通过复用一种快速IIR滤波器算法，能在1 μs时间内实现包含6组不同时间常数和幅度的预增强运算. 实验证明该系统具有通用性好、体积小和成本低等特点，为磁共振谱仪的研制提供了一种紧凑、灵活的梯度波形发生方案. 

关键词: 核磁共振成像(MRI), 梯度计算模块, 现场可编程门阵列, 波形预增强

Abstract:

A versatile digital gradient calculation module with high integration level was developed for magnetic resonance imaging. Based on a single field programmable gate array (FPGA) system, this apparatus operates real-time calculations of the gradient waveforms for oblique acquisition and preemphasis with a 16-bit parallel interface. Gradient profiles from the G_X, G_Y and G_Z channels are stored in the FPGA embedded memory blocks, and loaded via the parallel interface. High-performance digital waveform preemphasis is achieved by iteratively implementing a scattered lookahead algorithm for compensation of eddy currents. The system has the merits of high reliability, good universality, small size and low cost, providing a compact and flexible scheme for gradient waveform generation.

Key words: MRI, gradient calculation module, field programmable gate array, waveform preemphasis

中图分类号:

R445.2

肖亮, 汤伟男, 王为民. 基于单片FPGA的磁共振成像梯度计算模块[J]. 波谱学杂志, 2010, 27(2): 163-171.

XIAO Liang, TANG Wei-Nan, WANG Wei-Min. An FPGA-Based Single-Chip Gradient Calculation Module for Magnetic Resonance Imaging[J]. Chinese Journal of Magnetic Resonance, 2010, 27(2): 163-171.

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