A fast Time Domain Integral Equation(TDIE) solver is presented for analysis of transient scattering from electrically large conducting complex objects.The numerical process of Marching-On-in-Time(MOT) method based TDI...A fast Time Domain Integral Equation(TDIE) solver is presented for analysis of transient scattering from electrically large conducting complex objects.The numerical process of Marching-On-in-Time(MOT) method based TDIE encounters high computational cost and exorbitant memory requirements.A group-style accelerated method-Plane Wave Time Domain(PWTD) algorithm,which permits rapid evaluation of transient wave field generated by temporally bandlimited sources,is employed to reduce the computational cost of MOT-based TDIE solvers.An efficient compressed storage technique for sparse matrix is adopted to decrease the enormous memory requirements of MOT.The scheme of the Multi-Level PWTD(MLPWTD)-enhanced MOT with compressed storage for sparse matrix is presented for analysis of transient scattering from electrically large complex objects in this paper.The numerical simulation results demonstrate the validity and efficiency of the presented scheme.展开更多
We show how to apply convolution quadrature(CQ)to approximate the time domain electric field integral equation(EFIE)for electromagnetic scattering.By a suitable choice of CQ,we prove that the method is unconditionally...We show how to apply convolution quadrature(CQ)to approximate the time domain electric field integral equation(EFIE)for electromagnetic scattering.By a suitable choice of CQ,we prove that the method is unconditionally stable and has the optimal order of convergence.Surprisingly,the resulting semi discrete EFIE is dispersive and dissipative,and we analyze this phenomena.Finally,we present numerical results supporting and extending our convergence analysis.展开更多
It is important but difficult to analyze the electromagnetic environment effect(E3) in the designing of modern airborne,sea,space,and ground systems.Thus a hybrid algorithm of time domain integral equation,finite diff...It is important but difficult to analyze the electromagnetic environment effect(E3) in the designing of modern airborne,sea,space,and ground systems.Thus a hybrid algorithm of time domain integral equation,finite difference time domain and modified nodal analysis(TDIE-FDTD-MNA) is developed to analyze the E3 of complex systems with cables and nonlinear circuit structures.The plane wave time domain(PWTD) enhanced TDIE method is adopted to solve field problems.The higher order FDTD(2,4) is adopted to solve cable problems.The MNA is adopted to obtain the response of complex circuits(with nonlinear structures).Numerical examples demonstrate the effectiveness of the proposed algorithm.展开更多
The Time-Domain-Integral-Equation (TDIE) method is proposed to analyze transient scattering interaction between a two-dimensional infinitely long conducting target with an arbitrary cross section and a one-dimensional...The Time-Domain-Integral-Equation (TDIE) method is proposed to analyze transient scattering interaction between a two-dimensional infinitely long conducting target with an arbitrary cross section and a one-dimensional rough surface. Based on the electric-field-integral-equation in time domain, the explicit and implicit solutions of MOT (Marching-on-time) are derived and presented. The current response at the center of the rough surface and the far electric field response with time in the composite model are calculated and analyzed. The numerical results are compared and verified with those obtained by conventional MOM-IDFT (Method of Moment-inverse discrete Fourier transform). Finally, the influence of the size, the location of the target and the incident angle on the current response and the far electric fields response are discussed in detail.展开更多
文摘A fast Time Domain Integral Equation(TDIE) solver is presented for analysis of transient scattering from electrically large conducting complex objects.The numerical process of Marching-On-in-Time(MOT) method based TDIE encounters high computational cost and exorbitant memory requirements.A group-style accelerated method-Plane Wave Time Domain(PWTD) algorithm,which permits rapid evaluation of transient wave field generated by temporally bandlimited sources,is employed to reduce the computational cost of MOT-based TDIE solvers.An efficient compressed storage technique for sparse matrix is adopted to decrease the enormous memory requirements of MOT.The scheme of the Multi-Level PWTD(MLPWTD)-enhanced MOT with compressed storage for sparse matrix is presented for analysis of transient scattering from electrically large complex objects in this paper.The numerical simulation results demonstrate the validity and efficiency of the presented scheme.
基金funding this research under grant number DMS-0811104.
文摘We show how to apply convolution quadrature(CQ)to approximate the time domain electric field integral equation(EFIE)for electromagnetic scattering.By a suitable choice of CQ,we prove that the method is unconditionally stable and has the optimal order of convergence.Surprisingly,the resulting semi discrete EFIE is dispersive and dissipative,and we analyze this phenomena.Finally,we present numerical results supporting and extending our convergence analysis.
基金supported by National Basic Research Program of China(973 Program)
文摘It is important but difficult to analyze the electromagnetic environment effect(E3) in the designing of modern airborne,sea,space,and ground systems.Thus a hybrid algorithm of time domain integral equation,finite difference time domain and modified nodal analysis(TDIE-FDTD-MNA) is developed to analyze the E3 of complex systems with cables and nonlinear circuit structures.The plane wave time domain(PWTD) enhanced TDIE method is adopted to solve field problems.The higher order FDTD(2,4) is adopted to solve cable problems.The MNA is adopted to obtain the response of complex circuits(with nonlinear structures).Numerical examples demonstrate the effectiveness of the proposed algorithm.
基金Supported by the National Natural Science Foundation of China (Grant No. 60571058)the Specialized Research Fund for the Doctoral Program of Higher Education of China (Grant No. 20070701010)
文摘The Time-Domain-Integral-Equation (TDIE) method is proposed to analyze transient scattering interaction between a two-dimensional infinitely long conducting target with an arbitrary cross section and a one-dimensional rough surface. Based on the electric-field-integral-equation in time domain, the explicit and implicit solutions of MOT (Marching-on-time) are derived and presented. The current response at the center of the rough surface and the far electric field response with time in the composite model are calculated and analyzed. The numerical results are compared and verified with those obtained by conventional MOM-IDFT (Method of Moment-inverse discrete Fourier transform). Finally, the influence of the size, the location of the target and the incident angle on the current response and the far electric fields response are discussed in detail.
