基于连续波的频域磁声耦合成像方法正问题研究

发布时间：2018-05-20 17:44

本文选题：磁声耦合成像 + 频域　；参考：《生物医学工程研究》2015年01期

【摘要】：磁声耦合成像常用的时域信号检测方法易受到电磁干扰,限制成像质量。提出频域磁声成像方法,通过锁相放大实现微弱声信号的检测,提高信号检测精度。本研究建立了频域磁声耦合正问题数学模型,基于正弦波激励,对简单电导率边界模型进行了仿真研究和实验验证。仿真研究表明信号频域幅值相位反映了介质声源分布。实验验证了仿真结果,实现了声源幅值锁相检测和空间定位,检测精度达到10-7Pa,实现了激励电流低于1m A下的声检测。本研究提出的频域磁声耦合成像方法,有利于提高微弱磁声信号检测精度,在低频激励下实现高分辨率成像,对实现磁声耦合成像的介质内部电导率研究具有积极意义。
[Abstract]:The time domain signal detection methods commonly used in magnetoacoustic coupling imaging are vulnerable to electromagnetic interference and limit the imaging quality. A frequency domain magnetoacoustic imaging method is proposed to detect weak acoustic signals by phase-locked amplification to improve the accuracy of signal detection. In this paper, the mathematical model of magnetoacoustic coupling forward problem in frequency domain is established. Based on sine wave excitation, the simple conductivity boundary model is simulated and verified by experiments. The simulation results show that the amplitude and phase of the signal in frequency domain reflect the distribution of the dielectric sound source. The simulation results are verified and the sound source amplitude phase-locked detection and spatial location are realized. The detection accuracy reaches 10-7Pa. the sound detection with excitation current below 1m A is realized. The frequency-domain magnetoacoustic coupling imaging method proposed in this paper is helpful to improve the detection accuracy of weak magnetoacoustic signals and to realize high-resolution imaging under low frequency excitation. It is of positive significance to study the internal conductivity of medium for magnetoacoustic coupling imaging.
【作者单位】：中国医学科学院北京协和医学院生物医学工程研究所;
【基金】：国家自然科学基金重点项目(51137004);国家自然科学基金资助项目(81171424) 天津市自然科学青年基金资助项目(13JCQNJC14000)
【分类号】：TN911.23;R445.2

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