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Showing 1 to 20 of 38 for “"Method of moments (MoM)"”.
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Efficient integral equation solution of electromagnetic scattering by arbitrarily shaped objects in planar, multilayered media
The solution of electromagnetic scattering by objects located in planar, multilayered media has long been the subject of active research. For layered-media integral equation solutions via the Method of Moments (MoM), the O($N\sp2$) matrix fill is often prohibitively expensive, even for problems of …
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Numerical Methods for Solving the Problem of Electromagnetic Scattering From Large Bodies
In the past two decades, the conventional method of moments (MoM) utilizing the subdomain basis functions has been widely used to solve a variety of electromagnetic scattering problems. However, the size of the scatterers that can be analyzed by using MoM is limited to only a few wavelengths due to …
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Low-Frequency Subsurface Electromagnetic Modeling
Subsurface electromagnetic (EM) methods are applied to obtain underground information that is not available from surface observations. This research develops numerical methods for subsurface electromagnetic modeling. The dissertation includes: (1) fast one-dimensional forward and inverse modeling, …
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Finite Element Method for Electromagnetic Scattering and Radiation From Complex Axisymmetric Structures
… also developed to compute scattering from a body of revolution (BOR) with appendages. First, the FEM is used to compute the scattering from the BOR with the appendages removed. The incident field on the appendages in the presence of the BOR is then known, and the method of moments (MoM) with an …
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Using the method of moments and Robin Hood method to solve electromagnetic scattering problems
… by using a surface integral formulation of Maxwell's equations, which discretizes the surface of the scatterer into thousands of triangles. The method of moments (MoM) was applied, which calculates the Green's functions between each triangle element. A matrix equation is obtained and …
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Wave propagation in lossy waveguide structures
… and uses a full-wave solution process. A set of coupled, vector integral equations which characterize the system are derived. The equations enforce the necessary boundary conditions on the tangential electric and magnetic fields at the boundaries separating the conductors and dielectrics. The …
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A Higher -Order Finite Element: Boundary Integral Method for Electromagnetic Scattering and Radiation From Bodies of Revolution
The hybrid finite element - boundary integral method (FE-BI) is used to compute the radar cross section (RCS) and radiated fields of bodies of revolution (BOR). This is a 2.5-D problem since it allows simulations in a 2-D domain to correspond to a full 3-D object. The interior region, which …
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High-frequency electromagnetic wave scattering from rough surfaces
… surface scattering problem is presented. The method employed, entitled the ""shooting and bouncing rays"" (SBR) method, is based on a combination of the geometric optics (GO) theory and the physical optics (PO) theory. The SBR method improves on the Kirchhoff approximation by considering the …
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Numerically efficient analysis of microstrip configurations using closed-form Green's functions
A general class of microstrip structures is investigated in this work by using a spatial domain Green's function. The derivation of the closed-form spatial domain Green's functions for the vector and scalar potentials is presented for a microstrip geometry with a substrate and superstrate for which …
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Technique for the design of matched antennas using method of moment-based greedy best-first search
"As the number of wireless devices continues to grow, technical requirements and design constraints are approaching the limits of antenna performance and feature integration. Complex multi-band antennas that must satisfy stringent volumetric constraints are pushing the use of optimization tools to …
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Electromagnetic scattering and induction models for spheroidal geometries
… for spheroidal geometries are desirable because of their versatility in modeling manmade and natural shapes includ- ing solid and hollow needles, spheres, and disks, while at the same time possessing analytic solutions. Coherent scattering from a collection of small dielectric spheroids …
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OpenMP-CUDA implementation of the moment method and multilevel fast multipole algorithm on multi-GPU computing systems
In this thesis, the method of moments (MoM) and the multilevel fast multipole algorithm (MLFMA) are implemented for GPU computation based on the hybrid OpenMP-CUDA parallel programming model. The resultant algorithms are called the OpenMP-CUDA-MoM and the OpenMP-CUDA-MLFMA, respectively. Both of …
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Modeling aperture radiation for RF interference applications
<p>"The first topic proposes a rigorous method of moments(MoM) solution to evaluate the shielding effectiveness of a metallic enclosure with apertures on top wall by formulating a pair of coupled mixed potential integral equations (MPIEs). Application of Ewald transform to the computation of …
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ADVANCED IMPLEMENTATIONS OF THE ITERATIVE MULTI REGION TECHNIQUE
<p>The integration of the finite-difference time-domain (FDTD) method into the iterative multi-region (IMR) technique, an iterative approach used to solve large-scale electromagnetic scattering and radiation problems, is presented in this dissertation. The idea of the IMR technique is to divide a …
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Fast multipole acceleration of periodic Green's function using spherical harmonics and Ewald summation
… for solving a periodic scattering problem using method of moments (MOM). The difference between the standard integral equations (EFIE and MFIE) and the ones used for periodic geometry is the use of periodic Green's function (PGF) over free-space Green's function (FGF). When expressed as a spatial …
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Exact Solutions to Electromagnetic Scattering Problems with Multi-Layered Oblate Spheroidal Geometry
Computational electromagnetic methods (CEM) play a critical role in the design and analysis of complex electromagnetic (EM) systems. CEM, such as the finite element method (FEM), finite-difference time-domain (FDTD), and method of moments (MoM), allow researchers and engineers to solve practical EM …
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Frequency and time domain analysis of carbon nanotubes with realistic shape and distribution
Carbon nanotube (CNT) composites have been of significant research interest in a wide range of applications. For electromagnetic applications, simplifying assumptions regarding the distribution and shapes of the CNTs are typically made because the exact three-dimensional CNT distribution in the …
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A Characteristic Mode Analysis of Conductive Nanowires and Microwires Above a Lossy Dielectric Half-Space
… led to their incorporation in a wide variety of applications. The purpose of this study is to investigate the effect of material on the electromagnetic response of these nanowires. We used the Method of Moments (MOM) for Arbitrarily Thin Wire (ATW) formulation as an efficient computational …
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New full wave theory for plane wave scattering by a rough dielectric surface - the fictitious current method
A new full wave method for scattering of plane waves from a rough dielectric surface is developed. This new theory begins by postulating a zero-order field solution which does not satisfy Maxwell's source-free field equations. The zero-order field, however, is made to satisfy Maxwell's source …
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