电磁波层析成像反演射线路径的探讨

在电磁波 CT 测试中，发射、接收探头间的电磁波射线发射点、接收点位置决定反演后成果数据记录点的位置。为了确定电磁波仪发射、接收探头记录点位置，对探头分别进行钢管屏蔽实验，实验表明电磁波仪工作时电磁波能量主要集中在两探头的馈电点及天线末端间近似于平行四边形的区域内，不宜直接地简化为一条直线，将平行四边形区域简化为4条线段进行电磁波层析成像反演计算更符合实际情况。在此基础上，提出对电磁波 CT 数据采取4条射线路径单独反演后，再将4个结果按综合平均的方法进行处理。将此种处理方法应用于武汉地铁岩溶勘察数据处理中，并与目前基于1条射线的反演处理方法进行对比、验证。对比剖面反演数据结果表明，在采用同一反演软件条件下4条射线路径综合反演法精度优于1条射线反演法。

Discussion on Inversion Ray Path of Electro-magnetic Computerized Tomography

In computerized tomography test,the position of recording point after data inversion is determined by the position of transmitting point and receiving point between the two probes.In order to find out the position of record-ing points,we carried out experiment on electro-magnetic probe shielding by steel pipes.The experiment show that the energy concentration area between the two probes is parallelogram,hence it is more reasonable to inverse paral-lelogram area with four electro-magnetic wave rays rather than one ray path.On this basis,we propose to obtain the four single inversion result from each ray path and average them as the final result.This method was applied to the data processing of karst exploration for Wuhan underground.Through comparison of inversion result,this method is verified to be more precise than single-path inversion in the environment of the same inversion software.