探地雷达信号的高阶时间域有限差分模拟  

USING HIGHER-ORDER FDTD FOR GROUND PENETRATING RADAR RESPONSE SIMULATION

作　　者：吴丰收[1] 曾昭发[1] 黄玲[1] 张玲玲[1] 

机构地区：[1]吉林大学地球探测科学与技术学院,吉林长春130026

出　　处：《物探化探计算技术》2009年第4期308-313,共6页Computing Techniques For Geophysical and Geochemical Exploration

基　　金：国家自然科学基金项目(40474042);2007年国家级大学生创新性实验计划项目(2007A62037)

摘　　要：探地雷达信号时域有限差分法模拟,多采用二阶精度的中心差分法近似(FDTD(2,2)),虽然计算简单,但数值色散误差较大,影响了模拟精度。在解决较复杂介质分布的探地雷达信号时,不能很好地反映信号的精细变化。而高阶时域有限差分模拟能减少数值色散带来的误差,提高了模拟的精度。采用各向异性完全匹配层(UPML)作为吸收边界条件,实现了高阶计算,有效地吸收边界电磁波反射,而且提高了计算效率。通过模拟的结果分析可知,高阶时域有限差分法能很好地提高模拟精度。The traditional finite difference time domain method(FDTD) in GPR simulation is 2nd-order accurate difference.Although it is simple,its numerical dispersion errors affect accuracy of numerical results.The 2nd-order FDTD is difficult to be applied in the complex model simulation.Higher-order finite difference time domain method(HO-FDTD) can be used to solve the problem of dispersion and low accuracy.We also use the uniaxial perfectly matched layer(UPML) as Absorb boundary,which has high accuracy in simulation.The available UPML is 2nd-order,and we adopt the UPML to 2M-order UPML.The simulation result from higher-order FDTD algorithm shows that the method is effective and precision of simulation has been improved very much.

关 键 词：探地雷达 时域有限差分 各向异性完全匹配层 正演模拟 

分 类 号：P631.4[天文地球—地质矿产勘探]