现代导航
現代導航
현대도항
MODERN NAVIGATION
2015年
5期
441-447,435
,共8页
姬伟杰%刘平%李杰%韩潇弘毅
姬偉傑%劉平%李傑%韓瀟弘毅
희위걸%류평%리걸%한소홍의
地下腔体成像%后向投影算法%时域有限差分法%时延补偿
地下腔體成像%後嚮投影算法%時域有限差分法%時延補償
지하강체성상%후향투영산법%시역유한차분법%시연보상
Underground Cavity Imaging%Back Projection Algorithm (BP)%Finite Difference Time Domain (FDTD)%Time Delay Compensation
为能有效地对地下空穴进行探测和识别,提出了一种基于基本振子线电流辐射模型的改进后向投影算法。分析了地下介质的物理模型,构建了地下腔体的成像模型及基于FDTD的全波电磁仿真模型,推导了半空间电磁波传播时延补偿的计算公式,验证了改进成像算法对地下腔体成像的有效性;分析了目标照射面结构对成像的影响,分别对照射面为凸面、平面、凹面三类目标进行了成像分析,得到能对凸面、平面照射面进行有效成像但不能对凹面照射面进行有效成像的结论,在岩、土体中孔穴的成像中得到了验证,并给出了多个孔穴存在时的三维像。
為能有效地對地下空穴進行探測和識彆,提齣瞭一種基于基本振子線電流輻射模型的改進後嚮投影算法。分析瞭地下介質的物理模型,構建瞭地下腔體的成像模型及基于FDTD的全波電磁倣真模型,推導瞭半空間電磁波傳播時延補償的計算公式,驗證瞭改進成像算法對地下腔體成像的有效性;分析瞭目標照射麵結構對成像的影響,分彆對照射麵為凸麵、平麵、凹麵三類目標進行瞭成像分析,得到能對凸麵、平麵照射麵進行有效成像但不能對凹麵照射麵進行有效成像的結論,在巖、土體中孔穴的成像中得到瞭驗證,併給齣瞭多箇孔穴存在時的三維像。
위능유효지대지하공혈진행탐측화식별,제출료일충기우기본진자선전류복사모형적개진후향투영산법。분석료지하개질적물리모형,구건료지하강체적성상모형급기우FDTD적전파전자방진모형,추도료반공간전자파전파시연보상적계산공식,험증료개진성상산법대지하강체성상적유효성;분석료목표조사면결구대성상적영향,분별대조사면위철면、평면、요면삼류목표진행료성상분석,득도능대철면、평면조사면진행유효성상단불능대요면조사면진행유효성상적결론,재암、토체중공혈적성상중득도료험증,병급출료다개공혈존재시적삼유상。
To investigate the detection and recognition of underground cavity, a novel modified back projection algorithm based on the linear current radiation model of basic dipole is presented. The underground dielectric is analyzed, and the imaging model of underground cavity is built which the measured data is obtained through the half space finite difference time domain (FDTD). The computation formula of time delay compensation caused by the dielectric mutation is derived. The imaging result validates the accuracy of the modified back projection algorithm, and the effect of target structure to imaging is analyzed. The imaging of underground cavity is then studied. As well, the 3D imaging of cavity is provided to strength the ability of modified back projection algorithm.