基于FPGA的高频超声成像实验平台

发布时间：2018-03-14 00:53

本文选题：高频超声　切入点：图像处理　出处：《中国生物医学工程学报》2015年05期 　论文类型：期刊论文

【摘要】：高频超声具有卓越的分辨能力,在临床和医学基础研究中都得到重要应用。新的图像和信号处理算法不断被提出来,用于提高其成像质量和获取新的信息。为了实验这些算法,需要一个通过编程来改变功能的实验平台,这个平台必须能进行高频超声扫描以采集图像,具备足够实验算法运行的硬件资源,而且能提供方便的调试手段。针对上述应用,提出一种基于FPGA的实验平台,用于研究10~50 MHz高频超声的图像和信号处理的实时算法。该平台具有与实验算法模块相独立的扫描控制器,可以保证在实验算法的调试过程中图像采集和显示均不受影响。系统以180 MHz的采样率采集射频信号,以大规模FPGA及其外围电路提供实验算法运行的空间,并预置可配置的带通滤波器、正交解调、降采样、基带信号幅度检测和对数压缩等处理模块。还开发一个RAM观测工具,专门用于读取处理过程中存入片外RAM的图像数据,以检验中间结果的正确性。采用10 MHz的超声探头,对志愿者眼球进行在体扫描实验,分别对平台的数据采集、带通滤波、幅度提取、对数压缩等模块进行验证。结果表明,带通滤波处理能有效滤除射频信号中的高频、低频噪声,在处理时钟选为50 MHz的条件下,对于每条探测深度为64 mm的扫描线,平台从数据采集至IQ降采样输出完毕,总时间为85.34μs,而幅度检测和对数压缩算法在340 ns中就可以完成。该处理速度完全能够满足成像的实时性要求。
[Abstract]:High frequency ultrasound has excellent resolution, have important applications in clinical and basic medical research. A new algorithm of image and signal processing has been put out for improving the imaging quality and obtain new information. In order to test these algorithms need a programmed to change the function of the experimental platform, the platform must be able to high frequency ultrasound scan to capture images, have run enough experiment algorithm hardware resources, and can provide a convenient debugging method. According to the application, the paper proposes an experiment platform based on FPGA, for the study of 10~ 50 MHz high frequency ultrasound image and signal processing of the real-time algorithm. The platform has a scan controller module and the experimental algorithm. Independent, can guarantee the image acquisition and display debugging process in the experiment of the algorithm are not affected. The system at 180 MHz sampling rate with RF signal The size of FPGA and its peripheral circuit provides experimental algorithm running space, and can be preset configuration of the band-pass filter, quadrature demodulation, downsampling, baseband signal amplitude detection and log compression processing module. Also the development of a RAM observation tool, specifically for the reading process image data stored in a RAM, the right to the inspection of the intermediate results. The ultrasonic probe is 10 MHz, the volunteers in the eye scanning experiments respectively on data acquisition platform, band-pass filtering, amplitude extraction, logarithmic compression module was verified. The results show that the band-pass filter can effectively filter out the high frequency and low frequency noise, RF signal, processing the clock in for 50 MHz, for each scan line detection depth of 64 mm platform, from data acquisition to IQ down sampling output is completed, the total time is 85.34 s, while the number of amplitude detection and compression algorithm in 340 It can be done in NS. The processing speed can fully meet the real-time requirements of imaging.

【作者单位】：上海理工大学医疗器械与食品学院;
【基金】：上海市研究生创新基金项目(JWCXSL1302)
【分类号】：TP391.41;R445.1

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