[HTT18-03] Evaluation of effectiveness of ground penetrating radar exploration method using polarization characteristics by model experiment and numerical simulation
First, we conducted a small-scale experiment of ground penetrating radar exploration in a tank filled with silica sand. Groundwater table can be changed in this tank. The water table was divided into five stages for the wide angle measurement. The measured antenna directions were set perpendicular and parallel to the side line. Next, we performed an electromagnetic wave propagation simulation in order to quantitatively determine the change in radar waveform caused by the water table and antenna direction using a three-dimensional Finite Difference Time Domain (FDTD) method, which is known as the main method of electromagnetic field analysis and fast calculation. As a result of comparing the experimental with the simulation results, the magnitude of the reflected wave and the time of arrival of the reflected wave were found to be agreeable with each other. The waveform also changed greatly, suggesting that differences in reflection characteristics due to the antenna direction as well as the radar spacing appeared. Using this difference, we plan to determine physical properties such as dielectric constant.