The TM-polarized electromagnetic scattering problem of a two-dimensional inho-mogeneous structure buried in lossy stratified media is presented. Analysis work consists of two parts mainly, derivation of the Green’s f...The TM-polarized electromagnetic scattering problem of a two-dimensional inho-mogeneous structure buried in lossy stratified media is presented. Analysis work consists of two parts mainly, derivation of the Green’s function of a filament buried in lossy stratified media and constitution of the electric field integral equation of the equivalent current caused by the differences between the inhomogeneities and the stratified media. Based on these works, illustrative numerical results are given to model inhomogeneous underground tubes in lossy stratified media, and to describe the scattering field affected by different factors such as permittivity distribution, dimension, and buried depth of the inhomogeneities and so on.展开更多
The solution of scattering problem of buried complex bodies needs to not only consider the scattering from the complex bodies, but also apply the boundary conditions in two different types of coordinate systems. This ...The solution of scattering problem of buried complex bodies needs to not only consider the scattering from the complex bodies, but also apply the boundary conditions in two different types of coordinate systems. This paper applies the conversion technique of vector wave functions combined with the three-dimensional unimoment method to effectively solve this type of complex electromagnetic problem. Using the conversion relations between the cylindrical and spherical vector wave functions, two types of boundary-value problems are conveniently jointed. Both the vector wave function expansion and the multipole expansion belong to eigen function expansion methods and have the same convergence rate. But the former is more rigorous in theory and needs to calculate only two types of eigen components while the latter needs to calculate four types.展开更多
In this paper,a new method for extracting the parameters of buried object is proposed.The center position and dielectric properties of 2-D buried object are estimated by means of a regression technique based on suppor...In this paper,a new method for extracting the parameters of buried object is proposed.The center position and dielectric properties of 2-D buried object are estimated by means of a regression technique based on support vector machine(SVM).The proposed method,after a proper training procedure,is able to reconstruct the center position and dielectric properties of a buried object inside a given investigation domain.Numerical simulation results indicate that SVM-based approach shows higher accuracy than the back-propagation neural networks(BPNN) algorithm.展开更多
基金Supported by the National Natural Science Foundation of China
文摘The TM-polarized electromagnetic scattering problem of a two-dimensional inho-mogeneous structure buried in lossy stratified media is presented. Analysis work consists of two parts mainly, derivation of the Green’s function of a filament buried in lossy stratified media and constitution of the electric field integral equation of the equivalent current caused by the differences between the inhomogeneities and the stratified media. Based on these works, illustrative numerical results are given to model inhomogeneous underground tubes in lossy stratified media, and to describe the scattering field affected by different factors such as permittivity distribution, dimension, and buried depth of the inhomogeneities and so on.
文摘The solution of scattering problem of buried complex bodies needs to not only consider the scattering from the complex bodies, but also apply the boundary conditions in two different types of coordinate systems. This paper applies the conversion technique of vector wave functions combined with the three-dimensional unimoment method to effectively solve this type of complex electromagnetic problem. Using the conversion relations between the cylindrical and spherical vector wave functions, two types of boundary-value problems are conveniently jointed. Both the vector wave function expansion and the multipole expansion belong to eigen function expansion methods and have the same convergence rate. But the former is more rigorous in theory and needs to calculate only two types of eigen components while the latter needs to calculate four types.
基金Supported by the National Natural Science Foundation of China (50679037,60671040)
文摘In this paper,a new method for extracting the parameters of buried object is proposed.The center position and dielectric properties of 2-D buried object are estimated by means of a regression technique based on support vector machine(SVM).The proposed method,after a proper training procedure,is able to reconstruct the center position and dielectric properties of a buried object inside a given investigation domain.Numerical simulation results indicate that SVM-based approach shows higher accuracy than the back-propagation neural networks(BPNN) algorithm.