基于GPR的地下管线图谱特征的正演研究

Research on Forward Simulating the GPR Image Characteristic of Underground Pipeline

基于探地雷达工作原理与二维FDTD正演模型,研究了在不同天线频率与天线间距的雷达测试参数下的管线雷达图像特征,分析了管线材质、管径、埋深和埋地介质等因素对管道雷达图像中双曲线特征的影响规律,对比了管线与不同几何形状空洞地质体的雷达图像差异。通过图谱规律的分析与研究,总结了复杂条件下探地雷达检测地下管线的图像识别规律,明确了实测探地雷达图像判识过程中目标图谱的典型特征。对提高地下管线雷达图像解释的合理性具有积极的促进作用,也为进一步开展探地雷达图像的反演研究奠定了基础。

Based on the principle of GPR（ ground penetrating radar} and two-dimensional finite difference time domain （ FDTD ） method, the work is to forward simulate the GPR image characteristic of underground pipelines un- der different antenna frequency and different antenna spacing, the influence of different material of underground pipe- line, different diameter of underground pipeline, different depth of underground pipeline and different underground media on image characteristics was analyzed. The contrasting between the GPR image characteristic of underground pipeline and that of the cavity of different geometry in underground media is carried out. Through the analysis and re- search on images, the law of image recognition for underground pipelines under complex condition by penetrating radar detection is summarized ; the characteristics of target image of the GPR in the process of image recognition is clarified. The above work is beneficial to interpret the GPR image and recognize underground pipeline from the GPR image.