磁声电导率检测系统设计及其线性扫频理论验证  

Design of magneto-acoustic-electrical detection system and verification of its linear sweep theory

作　　者：戴明 陈思平 李芳芳 陈冕 林浩铭 陈昕 

机构地区：[1]深圳大学医学部生物医学工程学院,广东深圳518060 [2]广东省医学信息检测与超声成像重点实验室,广东深圳518060

出　　处：《生物医学工程学杂志》2018年第1期99-105,共7页Journal of Biomedical Engineering

基　　金：国家自然科学基金(61427806;81601510)

摘　　要：临床研究证实病灶组织的早期诊断能显著降低患癌风险,由于磁声电成像具有高分辨率和高对比度优势,因而有望成为一种新的检测方法。本文采用模块化设计思维,设计并实现了一款低成本、数字化磁声电导率检测系统,并提出线性调频连续波激励洛伦兹力电阻抗检测理论,通过0.5%NaCl均匀仿体实验,清晰获得与实际物理尺寸一致的均匀仿体电导率曲线,验证了线性扫频理论应用在本系统是准确且可行的。同时,1 000μs线性扫频时宽所获得分辨率优于500μs和1 500μs,提示线性扫频时宽是影响电导率分辨率的重要因素。通过对不同浓度NaCl均匀仿体的实验,得到了相同结论,证明了本系统的可重复测量性。Clinical studies had demonstrated that early diagnosis of lesion could significantly reduce the risk of cancer. Magneto-acoustic-electrical tomography （MAET） is expected to become a new detection method due to its advantages of high resolution and high contrast. Based on thinking of modular design, a low-cost, digital magnetoacoustic conductivity detection system was designed and implemented in this study. The theory of MAET using chirp continuous wave excitation was introduced. The results of homogeneous phantom experiment with 0.5% NaCl clearly showed that the conductivity curve of homogeneous phantom was highly consistent with the actual physical size, which indicated that the chirp excitation theory in our proposed system was correct and feasible. Besides, the resolution obtained by 1 000 μs sweep time was better than that obtained by 500 μs and 1 500μs, which means that sweep time is an important factor affecting the detection resolution of the conductivity. The same result was obtained in the experiments carried out on homogeneous phantoms with different concentrations of NaCl, which demonstrated the repeatability of our proposed MAET system.

关 键 词：磁声电成像 微弱信号检测 线性扫频 数字信号处理 

分 类 号：TH77[机械工程—仪器科学与技术]