Development of a chirp radar-type microwave computed tomography with the rotational scanner used for animal experiments

开发用于动物实验的带有旋转扫描仪的线性调频雷达型微波计算机断层扫描

基本信息

批准号：
09558116
负责人：
MIYAKAWA Michio
金额：
$ 8.06万
依托单位：
Niigata University
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (B)
财政年份：
1997
资助国家：
日本
起止时间：
1997 至 1998
项目状态：
已结题

项目摘要

The prototype system of the chirp radar-type microwave computed tomography (CP-MCT) was developed for noninvasive thermometry of the human body. High speed imaging of CP-MCT has been attempted in this study by introducing the rotational scan in the tomographic measurement. The prototype system, which uses the chirp pulse signal from 1 GHz to 2 GHz, collects projection data by repeating the translational scan and rotational scan of a pair of the transmitting- and receiving-antenna. The spatial resolution of the prototype system is estimated at approximately 1cm and 0.7 degree temperature variation has been visualized, although it takes approximately 100 minutes for data acquisition.The developed rotational scanner is composed of a transmitting antenna that is the dielectric loaded transmitting antenna and a receiving array antenna, which is composed of 21 small dipole antennas. Chirp pulse signal from 1 GHz to 2 GHz is irradiated from the transmitting antenna to a target immersed in saline solution. Since gain pattern of the dielectric-loaded waveguide antenna is fairly broad so that, fan beam projection is secured. The transmitting- and receiving-antenna are facing each other at a distance of 282 mm. Each dipole is arranged at a distance of 14.7 mm from adjacent dipole antennas to reduce the mutual coupling effect. Where, fan angle of the scanner becomes 60 degrees.Spatial resolution of the developed scanner is the same value with the predicted one that is worse than that of the prototype system due to its coarse sampling interval of the rotational scanner. However, this enabled us to develop the new rotational scanner with 41 small dipole antennas for animal experiments. It requires only 90 seconds for data acquisition.In addition to high speed imaging, image deblurring technique has also been developed by using the point spread function computed by FD-TD method.

开发了用于人体无创温度法的CHIRP雷达型微波计算机断层扫描（CP-MCT）的原型系统。在这项研究中，通过在层析成像测量中引入旋转扫描，尝试了CP-MCT的高速成像。使用从1 GHz到2 GHz的CHIRP脉冲信号的原型系统通过重复一对传输和接收 - 安坦纳的翻译扫描和旋转扫描来收集投影数据。原型系统的空间分辨率估计约为1厘米，温度温度变化已大约可视化，尽管大约需要100分钟才能获取数据。从1 GHz到2 GHz的CHIRP脉冲信号从传输天线辐射到浸入盐水溶液中的靶标。由于介电载体的波导天线的增益模式相当宽，因此可以保护风扇束投影。传输和接收 - 安特纳（Antenna）的距离为282 mm。每个偶极子与相邻偶极天线的距离排列为14.7毫米，以降低相互耦合的效果。在这里，扫描仪的风扇角度变为60度。发达的扫描仪的空间分辨率是相同的值，而预测的值则比原型系统的较差，这是由于其旋转扫描仪的粗抽采样间隔。但是，这使我们能够使用41个小偶极天线来开发新的旋转扫描仪，用于动物实验。数据采集仅需要90秒。除了高速成像外，还使用FD-TD方法计算的点扩展函数还开发了图像脱毛技术。