Yong Heui Cho - 21DOCS Test Area

Yong Heui Cho

Professor at Mokwon University

Yong Heui Cho received his B.S. degree in electronics engineering from Kyungpook National University, Daegu, South Korea, in 1998, and his M.S. and Ph.D. degrees in electrical engineering from the Korea Advanced Institute of Science and Technology (KAIST), Daejeon, South Korea, in 2000 and 2002, respectively. From 1993 to 1995, he was with the Republic of Korea (ROK) Army, Uijeongbu, South Korea. From 2002 to 2003, he was a Senior Research Staff with the Electronics and Telecommunications Research Institute (ETRI), Daejeon, South Korea. In 2003, he joined the School of Information and Communication Engineering, Mokwon University, Daejeon, South Korea, where he is currently a Professor. In 2026, the School plans to rebrand itself as the Department of Game Software Engineering. From 2011 to 2012, he was a Visiting Professor with the Department of Electrical and Computer Engineering, University of Massachusetts Amherst, Amherst, MA, USA. From 2019 to 2020, he was a Visiting Researcher with the Center for Electromagnetic Metrology, Korea Research Institute of Standards and Science (KRISS), Daejeon, South Korea. His current research interests include electromagnetic wave theory and scattering, parallel and distributed numerical methods, and EM simulation engines.

Daejeon, Korea

Public Documents 2

Theoretical Implementation of a Quasi-isotropic Antenna with Almost Everywhere Isotro...

Yong Heui Cho

and 1 more

July 08, 2024

A fundamental radiation limit for quasi-isotropic antennas is rigorously presented utilizing vector spherical modes within the framework of a mode-matching technique. The theoretical derivation is substantiated through diverse numerical analyses demonstrating that quasi-isotropic radiation employing an omnidirectional antenna is realizable with unity gain across nearly all angles and a maximal gain of 1.1929 (0.7660 dBi) at specific finite angles attributable to the Gibbs phenomenon. Practical implementation necessitates the introduction of a linear array comprising traditional element antennas such as Hertzian dipoles, half-wave dipole antennas, and rectangular patch antennas. Our array configuration is validated using commercial software packages, and the quasi-isotropic radiation patterns they generate exhibit favorable agreement. The ratio between the numbers of element antennas and effective Legendre modes governs a relative convergence that influences radiation characteristics, thereby indicating the existence of an optimal ratio for achieving quasiisotropic radiation while minimizing the mean absolute error (MAE).

Shooting and bouncing rays for sparse particles (SBR-SP) applied for multiple magneto...

Yong Heui Cho

and 4 more

February 15, 2023

A numerically efficient method of shooting and bouncing rays for sparse particles (SBR-SP) is presented to analyze a large two-dimensional (2D) array of magnetodielectric circular cylinders which are distributed with any positions, sizes, and media on the xy-plane. Iterative- and closed-forms of the SBR-SP are used to understand the convergence and accuracy characteristics of a large array of cylinders and we also compare them with the results obtained by a mode-matching technique, thus resulting in favorable agreement. Especially, the closed-form of the SBR-SP with GPU acceleration is fast and accurate enough to obtain various echowidth behaviors of a 80×80 square array within 71.8 s. In addition, a statistical analysis for a randomly distributed array with 6,400 elements is conducted in terms of mean and standard deviation and we obtain that initial shooting rays excited by an incident field are strongly dominant in statistical behaviors of scattering patterns. Our algorithm based on the SBR can be extended to three-dimensional (3D) problems where we model a large array of lossy dielectric spheres for the estimation of rain attenuation and signal variation.