合成孔径序列波束形成轴向运动补偿方法

发布时间：2018-10-10 14:55

【摘要】：合成孔径序列波束方法是一种新颖的医学超声成像方法,采用两个阶段的波束形成,在传统的超声成像系统中实现合成孔径成像,在不需要存储和传输大量射频回波数据的情况下,提高医学超声图像的分辨率。该方法的前提是假设成像目标静止不动,而通过仿真分析发现运动会造成成像目标位置错误。针对此问题,提出一种合成孔径序列波束形成运动估计和补偿方法:首先通过在同一位置连续发射接收两次以获取用于运动估计的数据,然后采用互相关方法对第一阶段波束形成得到的低分辨率图像进行运动估计和补偿,再对其做第二次波束形成得到高分辨率图像。Field II仿真结果显示,所提出的运动补偿方法可以得到正确的目标位置。对于运动速度为0.1 m/s的点目标,运动补偿后的平均横向分辨率与静止点目标相比仅降低2.03%,对比度降低2.7 d B。对于运动速度为0.2 m/s的囊目标,运动补偿后图像的对比度分辨率较静止情况仅降低8.53%,进一步说明所提出的运动补偿方法有效。
[Abstract]:Synthetic aperture sequence beamforming is a novel medical ultrasonic imaging method, which uses two stages of beamforming to realize synthetic aperture imaging in traditional ultrasonic imaging systems. The resolution of medical ultrasound images is improved without the need to store and transmit a large amount of RF echo data. The premise of this method is to assume that the imaging target is stationary, and through simulation analysis, it is found that the position of the imaging target is wrong due to the sports. To solve this problem, a synthetic aperture sequence beamforming motion estimation and compensation method is proposed. Firstly, two successive transmissions are received at the same position to obtain the data for motion estimation. Then the motion estimation and compensation of the low-resolution image obtained from the first stage beamforming are carried out by cross-correlation method, and the. Field II simulation results of the high-resolution image are obtained by the second beamforming. The proposed motion compensation method can get the correct target position. For a point target with a velocity of 0.1 m / s, the average lateral resolution after motion compensation is only 2.03 lower than that of a stationary point target, and the contrast is reduced by 2.7 dB. For the capsule target with a velocity of 0.2 m / s, the contrast resolution of the motion compensated image is only 8.53 lower than that of the stationary case, which further shows that the proposed motion compensation method is effective.
【作者单位】：中国科学院声学研究所;
【基金】：国家自然科学基金(11204346) 中国科学院声学研究所所长择优基金(Y454221341) 中国科学院声学研究所创新前瞻项目(Y154211341)
【分类号】：R445.1

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