Algorithms

An electromagnetic theory, an art of four small equations, can propose revolutionary solutions for the development of advanced passive and active devices, even for next generation communication services. The Applied & Computational Electromagnetics (ACE) Lab is continuously studying and inventing the novel field formulations toward technological breakthrough.

Overlapping T-block Method (OTM)

An overlapping T-block method (OTM) for the problems of electromagnetic scattering and dispersion relations was proposed in 2002 to obtain analytic yet numerically efficient closed-form solutions by combining a mode-matching technique (MMT) and a Green's function approach (GFA). Judicious combination of MMT and GFA is possible owing to cancelation of virtual currents. The OTM enables us to systematically divide an original geometry into several overlapping T-blocks, thus obtaining the novel analysis schemes for fast CPU time, better accuracy, and wide versatility. Utilizing the OTM, the dispersion relations of several ridge waveguides (2002) and axially grooved rectangular waveguides (2003) were analytically computed. The scattering problems for multiple rectangular grooves (2006/2008/2011), waveguide T-junctions (2004), waveguide filters (2007), and flanged coaxial lines (2012) were also dealt with the OTM.

• 2D OTM Formulations for TE or TM Modes

• 3D OTM Formulations for TE and TM Modes

• Related Achievements (International Journals)

1. IEEE TMTT (Oct. 2002)
2. IEEE TAP (Dec. 2011, May 2010, Feb. 2006)
3. IEEE MWCL (Nov. 2007)
4. IEE/IET MAP (Oct. 2008, Dec. 2004)
5. IET EL (Nov. 2003)
6. PIER M/L (2012, 2011)

Periodic-Scattering Theory of Diffraction (PSTD) for Periodic Structures

Dielectric periodic structures with very small radius have recently been used for nano-structures such as biosensors, nano-antennas, polarization selective surface, and terahertz transmission lines. Therefore, it is of theoretical and practical interest to rigorously obtain the asymptotic diffraction formulations of semi-infinite number of magnetodielectric periodic structures based on a periodic-scattering theory of diffraction (PSTD). We further extend them to large number of periodic arrays for nano-structures. Using the mixed coordinate systems and common-area concept, analytic and fast-convergent scattering solutions of periodic circular cylinders (2013) were obtained. The proposed PSTD can be generalized to magnetodielectric periodic arrays with truncated edges by extending a diffraction methodology developed for metallic rectangular grooves (2008/2011).

• Related Achievements (International Journals)

1. IEEE TAP (May 2018, Mar. 2013)
2. IET MAP (Oct. 2008)
3. PIER M (2011)