摘要
同传统的动态聚焦医学成像相比 ,高帧率超声成像系统通过一次发射事件就可得到一帧图像 ,故可达到极高的帧率。但在实际应用中 ,由于仅发射一次超声波束来成像 ,回波信号较弱 ,易受噪声干扰 ,使成像质量降低。为了提高系统信噪比 ,本文采用巴克码作为激励信号 ,利用巴克码所具有的尖锐自相关函数性质来构造匹配滤波器抑制噪声。计算机仿真结果表明系统信噪比有了一定的提高 ,成像质量得到了改善。
Compared with traditional dynamic focusing medicine imaging system, the high frame rate (HFR) ultrasonic imaging system only requires one transmission event to construct an image, so it can reach an ultra high frame rate. But due to one transmission event the received signal is so weak that the quality of constructed image is easily affected by noise. A method, which uses Barker code as excited signal, is presented in the paper to overcome the problem. Taking advantage of the Barker code's property of sharp auto-correlation, a kind of matched filter based on the code is designed to suppress the noise in the echo signal. Computer simulation shows the method is effective, which increases SNR of the system and improves the quality of image.
出处
《北京生物医学工程》
2004年第4期251-253,308,共4页
Beijing Biomedical Engineering
基金
中国科学技术大学归国留学基金资助
