December 1, 2014, 1:00 pm - 3:00 pm

Deans Conference Room ENGR B214

Higher Order Volume/Surface Integral Equation Modeling of Antennas and Scatterers Using Diakoptics and Method of Moments

Abstract: The principal objective of this dissertation is to develop, test, and optimize accurate, efficient, and robust computational methodology and tools for modeling of general antennas and scatterers based on solutions of electromagnetic integral equation formulations using the method of moments (MoM) and diakoptics. The approaches and implementations include the volume integral equation (VIE) method and its hybridization with the surface integral equation (SIE) method, in two ways. The first way combines the VIE method for dielectric parts and the SIE method for metallic parts of the structure. The second way performs subdivision of the entire structure into SIE domains of different constant permittivities, while modeling the inhomogeneity within each domain by the VIE method and employing different Greenâ€™s functions, with describing the inhomogeneity within each domain in terms of a perturbation with respect to the background permittivity. The first approach is very suitable for analysis of composite wire-plate-dielectric radiation/scattering structures. The second approach provides a particularly efficient solution to problems involving inhomogineities embedded within high-contrast homogeneous dielectric scatterers. The efficiency of computation is enhanced by applying the diakoptic domain decomposition. In the VIE-SIE diakoptic method, the interior diakoptic subsystems containing inhomogeneous dielectric materials are analyzed completely independently applying the VIE-SIE MoM solver, and the solution to the original problem is obtained from linear relations between electric and magnetic surface-current diakoptic coefficients on diakoptic surfaces, written in the form of matrices. The techniques implement Lagrange-type generalized curved parametric hexahedral MoM-VIE volume elements and quadrilateral MoM-SIE and diakoptic patches of arbitrary geometrical-mapping orders, and divergence-conforming hierarchical polynomial vector basis functions of arbitrary current expansion orders. The hexahedra can be filled with inhomogeneous dielectric materials with continuous spatial variations of the permittivity described by Lagrange interpolation polynomials of arbitrary material-representation orders. Numerical computation is further accelerated by MPI parallelization to enable analysis of large electromagnetic problems.

Adviser: Branislav Notaros

Co-Adviser: N/A

Non-ECE Member: Iuliana Oprea

Member 3: Steven Reising, V. Chandrasekar, Ali Pezeshki

Addional Members: N/A

Publications:

1. E. Chobanyan, M. M. IliÄ‡, and B. M. NotaroÅ¡, â€œDouble-Higher-Order Large-Domain Volume/Surface Integral Equation Method for Analysis of Composite Wire-Plate-Dielectric Antennas and Scatterersâ€, IEEE Transactions on Antennas and Propagation, vol. 61, No. 12, pp. 6051-6063, December 2013

2. E. Chobanyan, , D. I. OlÄ‡an, M. M. IliÄ‡, and B. M. NotaroÅ¡, â€Volume Integral Equation Based Diakoptic Domain-Decomposition Method for 3-D Electromagnetic Scattering Analysisâ€, IEEE Transactions on Antennas and Propagation, under revision

3. E. Chobanyan, M. M. IliÄ‡, and B. M. NotaroÅ¡, â€ Lagrange-type Modeling of Continuous Permittivity Variation in Double-Higher-Order Volume Integral Equation Methodâ€, Radio Science, under revision

4. M. Kabir, Md. A. H. Talukder, R. Khazaka, M. A. Dolatsara, E. Chobanyan, A. Smull, S. Roy, and B. M. NotaroÅ¡, â€œNon-Intrusive Pseudo Spectral Approach for Stochastic Macromodeling of EM Systems using Deterministic Full-wave Solversâ€, 23rd Conference on EPEPS 2014, 26-29 October, 2014

5. B. M. NotaroÅ¡, M. M. IliÄ‡, D. I. OlÄ‡an, M. DjordjeviÄ‡, A. B. ManiÄ‡, and E. Chobanyan, â€Hybrid Higher Order Numerical Methods in Electromagneticsâ€, International Conference on Electromagnetics in Advanced Applications, 3-9 August, 2014

6. E. Chobanyan, M. M. IliÄ‡, and B. M. NotaroÅ¡, â€œScattering Analysis Using Generalized Volume-Surface Integral Equation Method of Momentsâ€, Submitted for 2014 IEEE Antennas and Propagation Society International Symposium (APSURSI), 6-12 July, 2014

7. N. J. Å ekeljiÄ‡, A. B. ManiÄ‡, E. Chobanyan, M. Thurai, V. N. Bringi, and B. M. NotaroÅ¡ , â€œElectromagnetic Scattering by Oscillating Rain Drops of Asymmetric Shapesâ€, Submitted for 2014 IEEE Antennas and Propagation Society International Symposium (APSURSI), 6-12 July, 2014

8. A. B. ManiÄ‡, E. Chobanyan, M. M. IliÄ‡, and B. M. NotaroÅ¡, â€œParallelization of Double Higher Order FEM and MoM Techniquesâ€, Submitted for 2014 IEEE Antennas and Propagation Society International Symposium (APSURSI), 6-12 July, 2014

9. E. Chobanyan, N. J. Å ekeljiÄ‡, A. B. ManiÄ‡, B. M. NotaroÅ¡ , and M. M. IliÄ‡, â€œAtmospheric Particle Scattering Computation Using Higher Order MoM-SIE Methodâ€, 2013 IEEE Antennas and Propagation Society International Symposium (APSURSI), 7-12 July, 2013

10. E. Chobanyan, D. I. OlÄ‡an, M. M. IliÄ‡, and B. M. NotaroÅ¡, â€œCombining Diakoptic, VIE-MoM, and SIE-MoM Approaches in Analysis of Dielectric Scatterersâ€, 2013 IEEE Antennas and Propagation Society International Symposium (APSURSI), 7-12 July, 2013

11. J. Notaros, E. Chobanyan, V. Chandrasekar, and B. M. Notaros, â€œAccurate and Efficient Full-Wave Electromagnetic Analysis of Scattering from Hailstones,â€ 2013 IEEE Antennas and Propagation Society International Symposium, July 7-12, 2013

12. E. Chobanyan, M. M. IliÄ‡, and B. M. NotaroÅ¡, â€œHigher Order Volume and Surface Integral Equation Modeling of 3-D Scattering and Radiation Problemsâ€, USNC-URSI National Radio Science Meeting, January 9-12, 2013

13. E. Chobanyan, J. NotaroÅ¡, V. Chandrasekar, and B. M. NotaroÅ¡, â€œAccurate Electromagnetic Modeling of Melting Hailâ€, USNC-URSI National Radio Science Meeting, January 9-12, 2013

14. E. Chobanyan, M. M. IliÄ‡, and B. M. NotaroÅ¡, â€œEfficient higher order volume-integral-equation modeling of dielectric scatterersâ€, 2012 IEEE Antennas and Propagation Society International Symposium (APSURSI), 8-14 July, 2012

15. N. J. Å ekeljiÄ‡, E. Chobanyan, M. M. IliÄ‡, and B. M. NotaroÅ¡, â€œRules for Adoption of Expansion and Integration Orders in Moment-Method Computation of Electromagnetic Scattering and Radiationâ€, USNC-URSI National Radio Science Meeting, January 4-7, 2012

Program of Study:

ECE444

ECE512

ECE641

ECE642

MATH560

MATH652

ECE779

N/A