Combined-field solution of composite geometries involving open and closed conducting surfaces

Combined-field integral equation (CFIE) is modified and generalized to formulate the electromagnetic problems of composite geometries involving both open and closed conducting surfaces. These problems are customarily formulated with the electric-field integral equation (EFIE) due to the presence of the open surfaces. With the new definition and application of the CFIE, iterative solutions of these problems are now achieved with significantly improved efficiency compared to the EFIE solution, without sacrificing the accuracy.


Hybrid CFIE-EFIE solution of composite geometries with coexisting open and closed surfaces
Ergül, Özgür Salih (2005-07-08)
The combined-field integral equation (CFIE) is employed to formulate the electromagnetic scattering and radiation problems of composite geometries with coexisting open and closed conducting surfaces. Conventional formulations of these problems with the electric-field integral equation (EFIE) lead to inefficient solutions due to the ill-conditioning of the matrix equations and the internal-resonance problems. The hybrid CFIE-EFIE technique introduced in this paper, based on the application of the CRE on the ...
Improving the accuracy of the surface integral equations for low-contrast dielectric scatterers
Ergül, Özgür Salih (2007-06-15)
Solutions of scattering problems involving low-contrast dielectric objects are considered by employing surface integral equations. A stabilization procedure based on extracting the non-radiating part of the induced currents is applied so that the remaining radiating currents can be modelled appropriately and the scattered fields from the low-contrast objects can be calculated with improved accuracy. Stabilization is applied to both tangential (T) and normal (N) formulations in order to use the benefits of d...
Improving the accuracy of the MFIE with the choice of basis functions
Ergül, Özgür Salih (2004-06-26)
In the method-of-moments (MOM) and the fast-multipole-method (FMM) solutions of the electromagnetic scattering problems modeled by arbitrary planar triangulations, the magnetic-field integral equation (MFIE) can be observed to give less accurate results compared to the electric-field integral equation (EFIE), if the current is expanded with the Rao-Wilton-Glisson (RWG) basis functions. The inaccuracy is more evident for problem geometries with sharp edges or tips. This paper shows that the accuracy of the M...
Hybrid Surface Integral Equations for Optimal Analysis of Perfectly Conducting Bodies
Karaosmanoglu, Bariscan; Ergül, Özgür Salih (2015-07-24)
We consider hybrid formulations involving simultaneous applications of the electric-field integral equation (EFIE), the magnetic-field integral equation (MFIE), and the combined-field integral equation (CFIE) for the electromagnetic analysis of three-dimensional conductors with arbitrary geometries. By selecting EFIE, MFIE, and CFIE regions on a given object, and optimizing these regions in accordance with the simulation requirements, one can construct an optimal hybrid-field integral equation (HFIE) that p...
Iterative solution of the normal-equations form of the electric-field integral equation
Ergül, Özgür Salih (2007-06-15)
In this paper, we show that transforming the original equations into normal equations improves the convergence of EFIE significantly. We present the solutions of EFIE by employing the least-squares QR (LSQR) algorithm, which corresponds to a stable application of the conjugate gradient (CG) algorithm on the normal equations. Despite the squaring of the condition number due to such a transformation into the normal equations, LSQR improves the convergence rate of the iterative solutions of EFIE and performs b...
Citation Formats
Ö. S. Ergül, “Combined-field solution of composite geometries involving open and closed conducting surfaces,” 2005, Accessed: 00, 2020. [Online]. Available: