FDTD法分析无载频脉冲探地雷达特性

Study about the Properties of Carrier-Free Ground Penetrating Radar by FDTD Method

本文首先利用三维FDTD法对集中电阻加载圆柱形偶极天线的近地面辐射特性进行了计算，给出了天线上电流波形并分析了加载电阻和有耗媒质参数等因素对电流波形的影响；分析并计算了天线“方向图”及其随天线高度和媒质参数变化的规律．其次，利用色散媒质中2．5维FDTD法迭代公式，模拟计算了地下目标雷达回波电平图，并与实际探测结果进行了对比，二者具有较好的一致性；分析了色散媒质参数对雷达探测深度的影响.

The radiating properties of a linear dipole antenna loaded by lumped resistors are firstly calculated by 3-D FDTD method. The current waveforms on the antenna are given. The influence of the loaded lumped resistors and the parameters of lossy media on the current waveforms is also calculated and analysed. The pseudo-color pictures of the objects buried in different media are calculated by 2. 5D FDTD methed. The comparison between the result obtained by FDTD method and that by our Ground Penetrating Radar (GPR) system is made,and excellent agreement is obtained. The parameters of lossy media to influence the detectable depth and the resolution of GPR are studied.