双功能多普勒超声成像仪数字信号处理系统的设计研究

【作者】 查鹏；

【导师】 尧德中；

【作者基本信息】 电子科技大学 ， 生物医学工程， 2007， 硕士

【摘要】 超声诊断做为四大影像学诊断方法之一,在医学临床上有着重要的应用。近年来,随着数字信号处理、微电子、计算机软硬件、机械、材料等方面的快速发展,超声诊断仪在许多方面都有了长足的进步,这其中数字化B超和数字化彩超是发展的重点,而最主要的难点之一是数字信号处理系统的设计。双功能多普勒超声成像仪同彩超一样都是在B型超声成像基础上利用多普勒效应获取血流的信息,只是彩超采用更多的信号处理技术获得信息来进行彩色显示,考虑到系统的庞大性和复杂性,本文主要致力于数字双功能多普勒超声成像仪信号处理系统的设计研究,对以后进一步进行彩超信号处理系统设计有很重要的意义。论文结合目前广泛应用的现场可编程逻辑阵列(FPGA)技术,确定了整个双功能多普勒超声成像系统的设计方案,并分析了FPGA器件及其设计方法,最主要的是在对超声信号理论进行深入研究和在数学推导的基础上,对信号处理中的关键技术:动态滤波、包络检波、对数压缩、解调、相域处理、频域处理等进行了数字化的设计,并对其中一些模块进行了有利于减少FPGA资源消耗的优化,最后通过对关键模块进行硬件编程和在计算机上进行仿真等方式表明采用该设计方案是可行的,而且可以降低系统复杂度,同时由于采用的是数字技术,能有效提高系统的精度。由于整个系统的庞大性和复杂性,系统只是在超声信号理论的支撑下进行的设计,但从整体上讲是对数字化超声诊断仪器,尤其是对数字彩超,仍具有一定的理论和实际价值,同时对从事相关领域的技术人员有一定的借鉴意义。更多还原

【Abstract】 Ultrasound diagnosis, one of the four most important diagnosis means, is used in medical field. Ultrasound diagnosis equipments have much enormous progress during these years, owing to the same rapid progress in the field of the digital signal process, the ability of designing hardware and software, micro-electronics, mechanism and the material used in equipments. Among these, the digital B mode ultrasound equipment and the digital color ultrasound diagnosis equipment are emphasis direction. The design of the digital signal processing system is one of the difficulties.As same as color ultrasound diagnosis equipments, Duplex Doppler Ultrasonic Imaging Apparatus also obtains blood flow information through Doppler Effect. The distinctness is that color ultrasound diagnosis equipments use more signal processing techniques to obtain blood flow information and their images are colorful images. Thinking of the hugeness and the complexity of the system, in this paper, the design of the signal processing system of Duplex Doppler Ultrasonic Imaging Apparatus is proposed. It is of great significance to the design of the signal processing system of the color ultrasound diagnosis equipment.This paper introduced the frame of Duplex Doppler Ultrasonic Imaging Apparatus based on FPGA. And the design method of Field Programmable Gate Array is analyzed. The most important of all is our particular design of the digital signal processing system based on the theory of ultrasonic signal and mathematic derivation. It includes dynamic filter, amplitude demodulation, data compression, processing techniques in phase domain and frequent domain etc. And some modules are optimized for reducing resource used in FPGA. At last we indicated that the design is feasible and can reduce the complexity through the design and the simulation of important modules, At the same time, the system is excellent beacaue of digital techniques.Due to the hugeness and the complexity of the system,we only designed the system based on the theory of ultrasonic signal.However,it still has some theoretical and practical values for designing ultrasound diagnosis equipments,especialy for the digital color ultrasound diagnosis equipment.At the same time,it is valuable for engineers who engage in this field.更多还原