Search

Your search keyword '"Cho, Jeahoon"' showing total 26 results
Start Over Author "Cho, Jeahoon"
26 results on '"Cho, Jeahoon"'

5. FDTD Modeling for the Accurate Electromagnetic Wave Analysis of Graphene

Author

Kim, Yeon-Hwa, Choi, Hongjin, Cho, Jeahoon, and Jung, Kyung-Young

Abstract

We develop a finite-difference time-domain (FDTD) method suitable for the electromagnetic (EM) analysis of graphene. In this work, we employ the modified Lorentz model for dispersion modeling, the two-dimensional (2-D) sheet model for geometrical modeling, and the complex-frequency-shifted (CFS)-perfectly matched layer (PML) for the absorbing boundary condition. In specific, the accurate complex-conjugate pole-residue (CCPR) dispersion model is first adapted for the electrical modeling of graphene by using the robust vector fitting. Next, the CCPR parameters are converted to the modified Lorentz parameters and then the modified Lorentz-based dispersive FDTD formulation is used to enhance the computational efficiency. In FDTD cell modeling, the 2-D sheet cells are allocated for graphene rather than the conventional FDTD cell-based modeling. Finally, CFS-PML are employed for terminating the computational domain to avoid the late-time instability. The presented FDTD approach is validated in numerical examples for graphene-based parallel plate waveguides.

Published
2024
Full Text
View/download PDF

20. Design of a miniaturized spiral antenna for partial discharge detection system.

Author

Lee, Juneseok, Cho, Jeahoon, Choi, Jaehoon, Choo, Hosung, and Jung, Kyung‐Young

Subjects
*SPIRAL antennas, *PARTIAL discharges, *BROADBAND antennas, *ANTENNA radiation patterns, *ULTRA-wideband antennas
Abstract

A miniaturized spiral antenna with a broadband balun for a partial discharge (PD) localization system is proposed. The proposed antenna has broadband characteristic from 925 MHz to 1.6 GHz and a unidirectional radiation pattern. The overall dimensions of the fabricated antenna are 80 × 80 × 40 mm3, which is the smallest size among antennas for the PD detection system. The measured −10 dB reflection bandwidth starts at 925 MHz, and the measured directivity of the antenna is about 6 dB in the frequency band. [ABSTRACT FROM AUTHOR]

Published
2018
Full Text
View/download PDF

Catalog

Books, media, physical & digital resources
See catalog results