水体的探地雷达成像数值模拟与实验比较研究

摘要

The imaging of pipes in a water-filled tank is investigated using a ground penetrating radar（GPR） with an antenna of 1.6 GHz center frequency.The radar profiles of metal and polyvinylchloride（PVC） pipes in different conditions such as depths,diameters,dielectric losses are achieved.A numerical simulation program of two-dimension finite difference time domain which can model a pipe of thin wall is built to compare with experiments.The results of numerical simulations are in good agreement with experiments.This paper discusses the differences and similarities of actual detect and simulated radar profile in an interpreted point of view.A series of hyperbola caused by the multiple reflections of electromagnetic wave between object to be detected and surface is analyzed.Slight differences between results of simulation and actual detect with relative high-loss dielectric are also investigated.%对中心频率为1.6GHz的探地雷达（GPR）进行水箱管线成像研究,获得了金属和聚氯乙烯（PVC）管线在不同深度、不同管径组合以及不同介质损耗等情况下的雷达剖面。建立了二维时域有限差分程序对实验进行数值模拟对比研究,该程序能对薄壁管线进行高精度建模。相同模型下的数值模拟结果与实验符合较好。从图像解释的角度重点讨论了实测与数值模拟的雷达剖面的异同,分析了电磁波多次反射造成的一系列双曲线现象,并探讨了高损耗介质的GPR数值模拟与实测结果略有不同的原因及解决对策。