多偏移距电磁波数值成像的高阶FDTD法研究  

High-order FDTD Method for Multi-offset Electromagnetic Numerical Imaging

作　　者：魏丽君[1] 汪科[1] 

机构地区：[1]湖南铁道职业技术学院,湖南株洲412001

出　　处：《数学的实践与认识》2017年第12期189-195,共7页Mathematics in Practice and Theory

摘　　要：数值模拟是数据处理和反演解释的重要环节,为提高高频电磁波层析成像技术在工程勘察中的解译准确性,采用高阶时间域有限差分法(FDTD(2阶时间精度,4阶空间精度))模拟电磁波在溶洞地电模型下的数值成像,并采用多偏移距模式采集电磁波道集.分析了电磁波的波场快照图和波形剖面图,总结了电磁波在溶洞地质体中的传播规律,为实际工程勘察工作提供可靠依据.数值试验结果表明,FDTD(2,4)能高精度模拟电磁波在溶洞复杂介质中的数值成像和多偏移距采集模式具有高效性和灵活性.Numerical simulation is an important part of data processing and inversion interpretation. In order to improve the efficiency and the accuracy of electromagnetic wave imaging technology in engineering survey, it is important to understand the propagation characteristics of electromagnetic waves by forward modeling. The finite-difference time- domain FDTD （2, 4） is used to simulate the numerical imaging of electromagnetic waves in karst caves. The multi-offset mode is used to acquire the electromagnetic wave gathers. Based on the analysis of the electromagnetic wave wavefield and the waveform profile, the paper summarizes the propagation law of electromagnetic waves in karst caves and provides reliable basis for practical engineering investigation. The experimental results show that FDTD （2, 4） can simulate the numerical imaging of electromagnetic waves in complex media with high accuracy. It also proves that the multi-offset acquisition mode has high efficiency and flexibility.

关 键 词：高阶时域有限差分 多偏移距 数值成像 工程勘察 

分 类 号：O441[理学—电磁学]