Reaserch On Doppler Ultrasound Machine

In recent dacades.with the rapid development of medical ultrasound, a great number of ground-breaking new technologies emerged. Among these is the Doppler Ultrasound Imaging technology.Compared with other medical imaging method such as X-ray Imaging and MRI, Doppler Ultrasound Imaging is low-cost,nonradiactive,noninvasive and real-time. So today, even though many new technologies emerge, it still occupies an irreplaceble position in medical diagnostic.On the literature review, the paper first reviews the development course of Doppler Ultrasound Imaging and makes it clear what is the significance and research method of this topic. Among all the Doppler Ultrasound Imaging technologies, Color Doppler Flow Imaging(its abbreviation CDFI is used in the follow content) is the most widely used one. So next, the paper foucus on the CDFI. CDFI contains a number of links. Each of these links is analyzed theoretically. The accuracy of CDFI is seriously affected by many factors, among them are the clutter filter and flow velocity estimation method we use. If the clutter filter could not effectively suppress the clutter signal or the estimation method could not correctly estimate the flow velocity, accuracy of CDFI will be severely degraded. Thus a detailed discussion about the clutter filter design and estimation method,comparison between their diferrent implementations will be given in this paper.Theoretically analyzation is not enough. This thesis also designs and implements the CDFI on MATLAB simulation platform using FieldII. With this simulation, cost of determining the effection of different parameters and comparison between different implementations is much reduced. This lays a solid foundation for implementing CDFI on hardware and is of high theoretical and practical value.