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Electromagnetic imaging of threedimensional dielectric objects with Newton minimization
(IEEE, 2014)We present a general framework for detecting the shape and electrical properties of unknown objects by using the Newton minimization approach for solving inversescattering problems. This procedure is performed by evolving ... 
Electromagnetic modeling of splitring resonators
(IEEE, 2007)In this paper, we report our efforts to model splitring resonators (SRRs) and their large arrays accurately and efficiently in a sophisticated simulation environment based on recent advances in the computational electromagnetics. ... 
Fast and accurate analysis of complicated metamaterial structures using a lowfrequency multilevel fast multipole algorithm
(200909)We present efficient solutions of electromagnetics problems involving realistic metamaterial structures using a lowfrequency multilevel fast multipole algorithm (LFMLFMA). Ordinary implementations of MLFMA based on the ... 
Fast and accurate solutions of extremely large scattering problems involving threedimensional canonical and complicated objects
(IEEE, 200907)We present fast and accurate solutions of extremely large scattering problems involving threedimensional metallic objects discretized with hundreds of millions of unknowns. Solutions are performed by the multilevel fast ... 
Fast and accurate solutions of scattering problems involving dielectric objects with moderate and low contrasts
(IEEE, 200708)We consider the solution of electromagnetic scattering problems involving relatively large dielectric objects with moderate and low contrasts. Threedimensional objects are discretized with RaoWiltonGlisson functions and ... 
Hierarchical parallelization of the multilevel fast multipole algorithm (MLFMA)
(IEEE, 2013)Due to its O(N log N) complexity, the multilevel fast multipole algorithm (MLFMA) is one of the most prized algorithms of computational electromagnetics and certain other disciplines. Various implementations of this algorithm ... 
Hierarchical parallelization of the multilevel fast multipole algorithm for the efficient solution of largescale scattering problems
(IEEE, 200807)We present the details of a hierarchical parallelization strategy, which provides higher efficiency than the previous parallelization approaches for MLFMA. We demonstrate the effectiveness of our algorithm on sphere problems ... 
Hybridizing physical optics with MLFMA for efficient scattering computations of threedimensional complex targets
(IEEE, 200907)The multilevel fast multipole algorithm (MLFMA) provides accurate and efficient solutions of electromagnetic scattering problems involving large and complicated structures. On the other hand, whenever applicable, accelerations ... 
Improving iterative solutions of the electricfield integral equation via transformations into normal equations
(Taylor and Francis, 20120403)We consider the solution of electromagnetics problems involving perfectly conducting objects formulated with the electricfield integral equation (EFIE). Dense matrix equations obtained from the discretization of EFIE are ... 
Improving the accuracy of the surface integral equations for lowcontrast dielectric scatterers
(IEEE, 2007)Solutions of scattering problems involving lowcontrast dielectric objects are considered by employing surface integral equations. A stabilization procedure based on extracting the nonradiating part of the induced currents ... 
Incomplete LU preconditioning for the electricfield integral equation
(, 2006)Linear systems resulting from the electricfield integral equation (EFIE) become illconditioned, particularly for largescale problems. Hence, effective preconditioners should be used to obtain the iterative solution with ... 
Investigation of various metamaterial structures using multilevel fast multipole algorithm
(IEEE, 2007)We consider accurate simulations of metamaterial (MM) structures consisting of split ringresonators (SRRs) and thin wires (TWs). We employ electricfield integral equation (EFIE) to formulate the scattering problems ... 
Iterative nearfield preconditioner for the multilevel fast multipole algorithm
(Society for Industrial and Applied Mathematics, 20100706)For iterative solutions of large and difficult integralequation problems in computational electromagnetics using the multilevel fast multipole algorithm (MLFMA), preconditioners are usually built from the available sparse ... 
Iterative solution of composite problems with the combinedfield integral equation
(IEEE, 2007)We consider the solution of electromagnetic problems related to microwave applications involving composite geometries with coexisting open and closed conductors. Combinedfield integral equation is introduced on the closed ... 
Memoryefficient multilevel physical optics algorithm for fast computation of scattering from threedimensional complex targets
(IEEE, 2007)Multilevel physical optics (MLPO) algorithm provides a speedup for computing the physicaloptics integral over complex bodies for a range of aspect angles and frequencies. On the other hand, when computation of the RCS ... 
Microwave imaging of threedimensional conducting objects using the newton minimization approach
(IEEE, 2013)In this work, we present a framework to detect the shape of unknown perfect electric conducting objects by using inverse scattering and microwave imaging. The initialguess object, which evolves to achieve the target, is ... 
MLFMA memory reduction techniques for solving largescale problems
(IEEE, 2014)We present two memory reduction methods for the parallel multilevel fast multipole algorithm. One of these methods uses data structures out of core, and the other parallelizes the data structures related to input geometry. ... 
A modified equivalence principle for open surfaces
(IEEE, 2014)We introduce a new method for expanding equivalent surface current densities over open surfaces. The new method is based on the equivalence principle, which is theoretically used with closed surfaces. Utilizing loworder ... 
Multilevel physical optics algorithm for fast solution of scattering problems involving nonuniform triangulations
(IEEE, 2007)This paper shows the computational efficiency of the multilevel physical optics (MLPO) algorithm can be further increased by employing nonuniform triangulations of the target surface so that the triangle size is not nearly ... 
On the accuracy of MFIE and CFIE in the solution of large electromagnetic scattering problems
(ESA Publications, 2006)We present the linearlinear (LL) basis functions to improve the accuracy of the magneticfield integral equation (MFIE) and the combinedfield integral equation (CFIE) for threedimensional electromagnetic scattering ...