发射调频信号提高医学超声图像的信号噪声比  

Transmitting Frequency-Modulated Signal to Increase Signal-to-Noise Ratio of Medical Ultrasound Image

作　　者：谷金宏[1] 王素品[1] 万明习[1] 

机构地区：[1]西安交通大学生物医学信息工程教育部重点实验室,西安710049

出　　处：《西安交通大学学报》2007年第6期741-745,共5页Journal of Xi'an Jiaotong University

基　　金：教育部科技创新工程重大项目培育基金资助项目(705046);教育部高等学校博士学科点专项科研基金资助项目(20050698044)

摘　　要：为了提高医学超声图像的信号噪声比，研究了调频超声发射的成像方法．该方法发射具有包络的线性调频超声，在不提高发射声压的情况下增加了发射能量，接收超声解调后形成图像信号．利用超声传感器的冲激响应模型和调频信号成像的调频解调原理，进行了超声成像的仿真研究．仿真结果表明：发射调频信号形成的图像与发射普通脉冲形成的图像相比，信噪比大致提高10dB．利用自行设计的调频信号发射超声成像实验系统，得到了仿体的B型超声图像．结果显示：该方法使图像信噪比提高大约5～8dB，随着成像深度增加，该方法的优势更加明显．To increase signal-to-noise ratio （SNR） of medical ultrasound image, a frequencymodulated （FM） ultrasound transmitted imaging method is developed, where a weighted linear FM ultrasound is transmitted to enhance the emission energy without increasing the emission ultrasound pressure, and the image signal is formed by the demodulated ultrasound. Employing the impulse response model of ultrasound transducer and the modulating-demodulating principle of FM signal, the simulation for ultrasound imaging is carried out. The simulation results show that the SNR of the image formed with FM signal transmitting gets 10 dB higher than that formed with traditional pulse transmitting. By the aid of the self-designed FM signal transmitting ultrasound imaging experiment system, the B-mode ultrasound images of phantom are gained. The results reveal that the SNR is enhanced by 5-8 dB with the proposed method, which performs better with the increasing imaging depth.

关 键 词：调频信号 超声成像 信号噪声比 

分 类 号：R445.1[医药卫生—影像医学与核医学] R318.6[医药卫生—诊断学]