提出了基于异构双核的低场核磁共振（Low-field Nuclear Magnetic Resonance，low-field NMR）接收机的设计，具有ARM（Adanced RISC Machines）和现场可编程门阵列（Field Programmable Gate Array，FPGA）先进的异构双核结构、高速的模数转换器（Analog to Digital Converter，ADC）采集、增益的可控以及可视化显示等特性，提高了整个系统的性能指标.设计中采用Xilinx公司的系统开发工具System Generator来实现内部信号处理功能.实验结果表明，数字接收机具有结构紧凑、可重构性强、采样速率高和成本低等特点，并且增益的可控使接收机获得了较大的动态范围，提高了重建图像的信噪比（Signal-to-Noise Ratio，SNR）.
A heterogeneous dual-core receiver system that combines advanced reduced instruction set computing (RISC) machines (ARM) and field programmable gate array (FPGA) is proposed for low-field nuclear magnetic resonance (NMR) applications. This system has advantages, such as high speed analog to digital converter (ADC) acquisition and variable gain control. In this design, the system generator, a system development tool from the Xilinx Company, can implement internal signal processing functions. Experimental results showed that, compared with the traditional receiver, the digital receiver had compact structure, strong reconstruction, high sampling rate and low cost. In addition, variable gain control enabled the digital receiver to achieve a large dynamic range such that the signal-to-noise ratio (SNR) of the reconstructed image could be improved.
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