In this paper,an adaptive polynomial chaos expansion method(PCE)based on the method of moments(MoM)is proposed to construct surrogate models for electromagnetic scattering and further sensitivity analysis.The MoM is a...In this paper,an adaptive polynomial chaos expansion method(PCE)based on the method of moments(MoM)is proposed to construct surrogate models for electromagnetic scattering and further sensitivity analysis.The MoM is applied to accurately solve the electric field integral equation(EFIE)of electromagnetic scattering from homogeneous dielectric targets.Within the bistatic radar cross section(RCS)as the research object,the adaptive PCE algorithm is devoted to selecting the appropriate order to construct the multivariate surrogate model.The corresponding sensitivity results are given by the further derivative operation,which is compared with those of the finite difference method(FDM).Several examples are provided to demonstrate the effectiveness of the proposed algorithm for sensitivity analysis of electromagnetic scattering from homogeneous dielectric targets.展开更多
An integration technique based on use of Monte Carlo Integration is proposed for Method of Moments solution of Electric Field Integral Equation. As an example numerical analysis is carried out for the solution of the ...An integration technique based on use of Monte Carlo Integration is proposed for Method of Moments solution of Electric Field Integral Equation. As an example numerical analysis is carried out for the solution of the integral equation for unknown current distribution on metallic plate structures. The entire domain polynomial basis functions are employed in the MOM formulation which leads to only small number of matrix elements thus saving significant computer time and storage. It is observed that the proposed method not only provides solution of the unknown current distribution on the surface of the metallic plates but is also capable of dealing with the problem of singularity efficiently.展开更多
We present an accurate spectral integral method(SIM)for the analyses of scattering from multiple circular perfect electric conductor(PEC)cylinders.It solves the coupled surface integral equations by using the Fourier ...We present an accurate spectral integral method(SIM)for the analyses of scattering from multiple circular perfect electric conductor(PEC)cylinders.It solves the coupled surface integral equations by using the Fourier series and addition theorem to decouple the system.The SIM has exponential convergence so that the error decreases exponentially with the sample density on the surfaces,and requires only about 2–3 points per wavelength(PPW)to reach engineering accuracy defined as higher than 99%accuracy(or with an error smaller than 1%).Numerical results demonstrate that the SIM is much more accurate and efficient than the method of moments(MoM),and thus can be potentially used as the exact radiation boundary condition in the finite element and spectral element methods.展开更多
Current surface integral equations used for computing scattering from targets with negative impedance boundary condition（IBC）are not efficient.A modified surface dual integral equation（M-SDIE）for targets with nega...Current surface integral equations used for computing scattering from targets with negative impedance boundary condition（IBC）are not efficient.A modified surface dual integral equation（M-SDIE）for targets with negative IBC is presented.A pure imaginary number is used to balance the formulations.It is proved that the M-SDIE is accurate and efficient with three numerical examples.The first numerical example shows that the M-SDIE is accurate compared with Mie.The second example shows that the presented SIE is efficient.In the third example,a missile head is selected to present the computing power of the M-SDIE.All the examples show that the M-SDIE is an efficient algorithm for negative IBC.展开更多
The volume-surface integral equation(VSIE) ,the surface integral equation(SIE) and the volume integral equation(VIE) of EM scattering problem are converted into linear equations with the method of moment,then the prec...The volume-surface integral equation(VSIE) ,the surface integral equation(SIE) and the volume integral equation(VIE) of EM scattering problem are converted into linear equations with the method of moment,then the precorrected-FFT method is used to solve the linear equations.To overcome the drawback of conventional stencil topology,two kinds of improved stencil topology,stencil topology B and stencil topology C,are presented,and the construction and actual performance of the three kinds of stencil topology are compared.Numerical results show that good agreement is observed between the P-FFT solutions combined with each of the three kinds of stencil topology and the standard solutions.Stencil B can significantly reduce the number of near-zone precorrections.Stencil C potentially holds for parallel multilevel P-FFT since grid overlapping never occurs between any stencils.展开更多
基金supported by the Young Scientists Fund of the National Natural Science Foundation of China(No.62102444)a Major Research Project in Higher Education Institutions in Henan Province(No.23A560015).
文摘In this paper,an adaptive polynomial chaos expansion method(PCE)based on the method of moments(MoM)is proposed to construct surrogate models for electromagnetic scattering and further sensitivity analysis.The MoM is applied to accurately solve the electric field integral equation(EFIE)of electromagnetic scattering from homogeneous dielectric targets.Within the bistatic radar cross section(RCS)as the research object,the adaptive PCE algorithm is devoted to selecting the appropriate order to construct the multivariate surrogate model.The corresponding sensitivity results are given by the further derivative operation,which is compared with those of the finite difference method(FDM).Several examples are provided to demonstrate the effectiveness of the proposed algorithm for sensitivity analysis of electromagnetic scattering from homogeneous dielectric targets.
文摘An integration technique based on use of Monte Carlo Integration is proposed for Method of Moments solution of Electric Field Integral Equation. As an example numerical analysis is carried out for the solution of the integral equation for unknown current distribution on metallic plate structures. The entire domain polynomial basis functions are employed in the MOM formulation which leads to only small number of matrix elements thus saving significant computer time and storage. It is observed that the proposed method not only provides solution of the unknown current distribution on the surface of the metallic plates but is also capable of dealing with the problem of singularity efficiently.
文摘We present an accurate spectral integral method(SIM)for the analyses of scattering from multiple circular perfect electric conductor(PEC)cylinders.It solves the coupled surface integral equations by using the Fourier series and addition theorem to decouple the system.The SIM has exponential convergence so that the error decreases exponentially with the sample density on the surfaces,and requires only about 2–3 points per wavelength(PPW)to reach engineering accuracy defined as higher than 99%accuracy(or with an error smaller than 1%).Numerical results demonstrate that the SIM is much more accurate and efficient than the method of moments(MoM),and thus can be potentially used as the exact radiation boundary condition in the finite element and spectral element methods.
基金Supported by the National Key Basic Research Program of China(973 Program)(2012CB720702)(61320601-1)the 111 Project of China(B14010)the National Natural Science Foundation of China(61421001,61371002)
文摘Current surface integral equations used for computing scattering from targets with negative impedance boundary condition（IBC）are not efficient.A modified surface dual integral equation（M-SDIE）for targets with negative IBC is presented.A pure imaginary number is used to balance the formulations.It is proved that the M-SDIE is accurate and efficient with three numerical examples.The first numerical example shows that the M-SDIE is accurate compared with Mie.The second example shows that the presented SIE is efficient.In the third example,a missile head is selected to present the computing power of the M-SDIE.All the examples show that the M-SDIE is an efficient algorithm for negative IBC.
文摘The volume-surface integral equation(VSIE) ,the surface integral equation(SIE) and the volume integral equation(VIE) of EM scattering problem are converted into linear equations with the method of moment,then the precorrected-FFT method is used to solve the linear equations.To overcome the drawback of conventional stencil topology,two kinds of improved stencil topology,stencil topology B and stencil topology C,are presented,and the construction and actual performance of the three kinds of stencil topology are compared.Numerical results show that good agreement is observed between the P-FFT solutions combined with each of the three kinds of stencil topology and the standard solutions.Stencil B can significantly reduce the number of near-zone precorrections.Stencil C potentially holds for parallel multilevel P-FFT since grid overlapping never occurs between any stencils.
