北京生物医学工程

一种改进的最小方差自适应波束形成超声成像方法

Ultrasonic imaging using an improved minimum variance beamforming

作者：刘红飞杜宏伟

单位：                      中国科学技术大学电子科学与技术系(合肥230027)        

关键词：前后向平滑；最小方差；相干系数；超声成像

分类号：

出版年·卷·期（页码）：2014·33·2（144-147）

摘要：

目的为提高医学超声成像过程中的对比度并改善自适应算法的鲁棒性，提出了融合相干系数(coherence factor,CF)与前后向平滑的自适应波束形成(forward-backward minimum variance,FBMV)超声成像方法。方法首先对阵元接收数据进行延时聚焦处理，利用前后向空间平滑技术去除回波信号的相关性，然后进行最小方差波束形成，同时计算回波信号的相干系数。最后利用相干系数加权前后向平滑的最小方差波束形成的结果，得到回波数据进行成像。结果仿真结果表明，相对于最小方差波束形成算法与传统的延时叠加波束形成算法，本文算法在对比度及鲁棒性方面均得到有效提高。结论本算法为实现高质量的超声成像系统提供了理论依据。

Objective In order to obtain high contrast and improve minimum variance(MV) robustness in medical ultrasound imaging,an ultrasound imaging method combining forward-backward minimum variance beamformer(FBMV) and coherence factor(CF) is presented.Methods Firstly,the data from the elements is delayed for focusing,forward-backward spatial smoothing can decorrelate the echo signal.Then the multi-channel data is used for minimum variance beamformer and to calculate the CF.In the end,the CF is used to weight the results of forward-backward minimum variance beamformer,and the medical images are achieved by the imaging system.Results The results show that this method is better than the minimum variance beamformer(MV) and delay-and-sum beamformer(DAS) in the aspects of contrast and robustness.Conclusions This method provides theory evidence for the realization of high-quality ultrasonic image system.

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