当前临床高场磁共振成像（MRI）系统要求成像仪控制台支持16个甚至32个接收通道，可以频繁和高速地进行数据传输并支持快速成像．基于此要求，本文研发了一个基于PowerPC处理器的数据传输模块，将其集成于自行研发的MRI成像仪控制台中，用于成像过程中控制台与计算机之间数据的高速传输．该模块以飞思卡尔公司的高性能PowerPC处理器—MPC8270为核心，运行嵌入式Linux操作系统．处理器与用户计算机之间通过百兆以太网连接，使用局部总线连接控制台的序列运行模块和数据采集模块（数量可扩展）．处理器响应数据采集模块发来的中断请求以快速读取和上传数据．本设计通过驱动程序的设计以保障响应的速度与可靠性．成像实验表明此设计方案能够满足多个接收通道数据快速获取与传输的需求．
High-field clinical magnetic resonance imaging (MRI) system often requires multiple-channel (i.e., 16 or 32) receivers that are capable of transmitting data at a high speed, especially during fast imaging. In this work, a data transmission module based on PowerPC processor is developed and integrated in a custom-built MRI spectrometer for high-speed data transmission between the spectrometer and the host computer. The module uses the Freescale's high-performance PowerPC processor MPC8270 as its core, and runs on the embedded Linux operating system. The processor and the computer are connected through a 100 M Ethernet network, while the sequence running the data acquisition modules (quantity scalability) is connected to the processor using a local bus. Responding to the interruption requests from the data acquisition module, the processor reads and uploads the data quickly. The speed and reliability of the response are guaranteed through the design of the driver program. The results of imaging experiments demonstrate that the design proposed can meet the high-speed data transmission requirements of multiple receiving channels.
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