基于自适应加权的在体长骨导波模式分离的研究

项目名称： 基于自适应加权的在体长骨导波模式分离的研究

项目编号： No.61201060

项目类型： 青年科学基金项目

立项/批准年度： 2013

项目学科： 电子学与信息系统

项目作者： 郑驰超

作者单位： 合肥工业大学

项目金额： 22万元

中文摘要： 骨质疏松症严重影响人类健康。超声导波测量长骨是一种新的检测骨质疏松症技术，具有相关性高，敏感性好,受试者易于接受等优点，但也存在严重缺陷：如导波信号在软组织中传播衰减严重，导波不易检测等，另外软组织内的超声信号干扰导波，影响模式分离。 为实现在体长骨导波模式准确分离，本项目根据同一频带的不同模式信号接收角差异性较大的特点，提出单阵元发射，多阵元接收及自适应阵列信号处理方案。该方法先采用多重信号分类法估计所提取模式导波的接收角，利用接收角做为来波方向设定导向矢量，通过最小方差准则计算权值，对阵列信号进行加权叠加，使得接收角方向信号得到增强，组织干扰信号被有效压制。另外，通过对导向矢量进行组织倾斜角补偿，进一步提高分离信号的准确性。 该研究在一定程度上克服了软组织对长骨导波信号的影响，实现了在体长骨导波模式准确分离，强化了导波测量技术的实用性，这对骨质疏松症检测具有重要意义。

中文关键词： 超声测量骨密度；长骨导波；超声成像；；

英文摘要： Osteoporosis has serious impact on human health. Detectiving the long bone with ultrasonic guided wave is a new technology for diagnosis of Osteoporosis. This method has very high correlation and good sensitivity, and is easy to receive. However, there are still some major defects with this method. The ultrasonic guided wave has serious attenuation with propagation in the soft tissue, so it is hard to detecte. Besides, the ultrasonic guided wave will be disturbed by the instrinsic ultrasound in the soft tissue and the mode seperation will be affected. In order to seperate the ultrasonic guided wave mode of long bone in vivo accurately , a new scheme is proposed in this project. In consideration of the big difference between the acceptance angles of different pattern signal under the same frequency band, the scheme uses one single element to transmit, multi-element to receive and adaptive array signal processing to extract signals. The acceptance angles are firstly estimated with the multiple signal classification, then used as the direction angles of the arrival wave to get the guided vectors. The weights are calculated using the least variance rule and employed on array signals for composition. In this process, the signals in the acceptance angles direction are strengthen, and interfering signals came from ti

英文关键词： Ultrasonic measurement for bone mineral density；Guide wave of long bone；Ultrasound imaging；；