摘要
3D ground-penetrating radar has been widely used in urban road underground disease detection due to its nondestructive,efficient,and intuitive results.However,the 3D imaging of the underground target body presents the edge plate phenomenon due to the space between the 3D radar array antennas.Consequently,direct 3D imaging using detection results cannot reflect underground spatial distribution characteristics.Due to the wide-beam polarization of the ground-penetrating radar antenna,the emission of electromagnetic waves with a specific width decreases the strong middle energy on both sides gradually.Therefore,a bicubic high-precision 3D target body slice-imaging fitting algorithm with changing trend characteristics is constructed by combining the subsurface target characteristics with the changing spatial morphology trends.Using the wide-angle polarization antenna’s characteristics in the algorithm to build the trend factor between the measurement lines,the target body change trend and the edge detail portrayal achieve a 3D ground-penetrating radar-detection target high-precision fitting.Compared with other traditional fitting techniques,the fitting error is small.This paper conducts experiments and analyses on GpaMax 3D forward modeling and 3D ground-penetrating measured radar data.The experiments show that the improved bicubic fitting algorithm can eff ectively improve the accuracy of underground target slice imaging and the 3D ground-penetrating radar’s anomaly interpretation.
三维探地雷达由于其无损、高效和探测结果较为直观的特点,近些年来在城市道路地下病害检测中得到了广泛应用。但是由于三维雷达阵列天线排布间隔的存在,造成地下目标体三维成像呈现边缘板块现象,导致采用探测结果直接三维成像无法反映地下实际空间分布特征。由于探地雷达天线宽波束极化,导致发射电磁波具有一定宽度,且呈现中间能量强两侧逐渐衰减的特性。针对上述问题,结合地下目标在空间上具有延续性的特点,构建了一种具有变化趋势特征的Bicubic高精度三维目标体切片成像拟合算法,利用天线宽角极化特性在算法中构建测线间变化趋势因子,将目标体变化趋势与边缘细节刻画相结合,实现了三维探地雷达探测目标高精度拟合。与其他常规拟合技术对比,拟合误差小。论文针对GpaMax 3D正演模拟和三维探地雷达实测数据进行了实验与分析,实验表明改进的Bicubic拟合算法有效地提高了地下目标切片成像的准确性,提高了三维探地雷达的异常解释精度。
基金
supported by The National Key Research and Development Program of China (2021YFC3090304)
The Fundamental Research Funds for the Central Universities,China University of Mining and Technology-Beijing (8000150A073).
