Electronics and Telecommunications Research Institute

Soongsil University

Information and Communications University Educational Foundation

Dong-Uk Sim

Jong Hwa Kwon

Sang Woon Kwak

Sang Il Kwak

Jae-Ick Choi

Hyung-Do Choi

Chang-Joo Kim

Je Hoon Yun

Seung Keun Park

Hyung Do Choi

Dong-Ho Kim

Hyeyeon Kwon

Jong-Hwa Kwon

Sangil Kwak

Yong Tae Moon

Young Jun Chong

Seong-Ook Park

Hyeon Seok Jang

Dongho Kim

Provided is a wireless channel reproduction device having a structure of an reverberation chamber. More specifically, the wireless channel reproduction device may minimize a measurement uncertainty by satisfying recommendations on spatial uniformity or field uniformity of a working volume and may be designed as an internal structure of an reverberation chamber including a plurality of mode agitators.

Wireless channel reproduction device

Provided is a mode stirring device. The mode stirring device includes a transmission antenna configured to output a wireless signal to measure wireless performance in an electromagnetic (EM) wave reverberation chamber, an antenna connection bar having one end coupled to a lower end of the transmission antenna, a crankshaft connected to another end of the antenna connection bar, and a motor configured to change a position of the transmission antenna by rotating the crankshaft.

Mode stirring device

Provided a reverberation chamber including a pair of a transmitting and receiving antenna and a reflection plate configured to reflect an electromagnetic wave output from the transmitting and receiving antenna to a working volume in a beam direction to improve a field uniformity of the working volume in the reverberation chamber and increase an applicability of the reverberation chamber.

Reverberation chamber

Disclosed is an electromagnetic wave reverberation chamber including a column-type mode stirrer including a plurality of plate-shaped electromagnetic wave reflectors connected by a metal column provided on a bottom of the electromagnetic wave reverberation chamber, a ceiling-type mode stirrer including a plurality of plate-shaped electromagnetic wave reflectors connected by a metal column provided on a wall surface of the electromagnetic wave reverberation chamber and disposed around a ceiling of the electromagnetic wave reverberation chamber, and a pyramidal mode stirrer including a plurality of pyramid-shaped electromagnetic wave reflectors and disposed on a wall surface of the electromagnetic wave reverberation chamber.

Electromagnetic wave reverberation chamber

Provided is a cover accessory for a wireless communication device, including an electromagnetic suppressing pattern layer on a surface adjoining at least one surface on which an electromagnetic wave is irradiated from the wireless communication device, wherein the electromagnetic suppressing pattern layer includes a first dielectric layer and a frequency selective surface (FSS) pattern with a unit cell having electromagnetic surface resistance periodically repeated thereon, and the FSS pattern is provided by etching the first dielectric layer to inject an FSS pattern material or by printing the FSS pattern material on the first dielectric layer.

Cover accessory including electromagnetic wave suppression function for wireless communication device

An electromagnetic wave reverberation chamber formed in the shape of a polyhedron includes an electromagnetic wave absorbing apparatus installed on at least one wall of metal conductors of the electromagnetic wave reverberation chamber. The electromagnetic wave absorbing apparatus having a shape of a roll screen and includes an electromagnetic wave absorbing film, a roll for rolling the one end of the electromagnetic wave absorbing film, a cover for covering the roll, and a fixing unit for fixing the other end of the electromagnetic wave absorbing film.

An electromagnetic wave reverberation chamber includes: an electromagnetic wave absorbing apparatus installed in an intended space of the electromagnetic wave reverberation chamber for adjusting a reflection characteristic of an inside of the electromagnetic wave reverberation chamber, wherein the electromagnetic wave absorbing apparatus have an electromagnetic bandgap structure including a plurality of unit cells arranged periodically.

A method of manufacturing a transparent film for reducing electromagnetic waves includes forming a first dielectric layer and forming a pattern layer on the first dielectric layer. The pattern layer is made of a transparent electrode material having surface resistance.

Transparent film for reducing electromagnetic waves and method of manufacturing the same

An apparatus for use in a communication device with an antenna protects a body from electromagnetic fields. The apparatus includes a sensing unit to sense a surrounding environment of the communication device, a variable element to perform a variable operation according to a voltage or current applied thereto. The apparatus further includes a variable element control unit to control the voltage or current according to the surrounding environment sensed by the sensing unit to cause the variable element to perform the variable operation, and an intelligent periodic structure coupled with the variable element, the intelligent periodic structure being configured to change an operation frequency of the wireless communication device according to the variable operation of the variable element and adjust a radiation pattern direction of the antenna.

Apparatus and method for body protection from electromagnetic fields

An electromagnetic wave absorbing device includes a ground layer formed of a metal conductor layer, a dielectric layer formed on the ground layer, and a unit cell pattern layer which is formed on the dielectric layer and made of resistive materials, wherein at least two electromagnetic bandgap-based unit cell patterns are periodically arranged on the unit cell pattern layer.

Electromagnetic wave absorbing device

A voltage controlled oscillator includes a split ring resonator (SRR) configured to have meta-material characteristics fabricated on a board, and an energy compensation circuit configured to cause resonant oscillation of the SRR. The energy compensation circuit is fabricated in the form of an integrated circuit.

Voltage controlled oscillator

A multilayer board for suppressing unwanted electromagnetic waves and noise includes: a power plane and a ground plane constituting a power distribution network; an electromagnetic wave suppression structure placed on the power plane or the ground plane; and a decoupling capacitor placed on the power plane or the ground plane, wherein the electromagnetic wave suppression structure and the decoupling capacitor are placed together.

Multilayer board for suppressing unwanted electromagnetic waves and noise

Provided are a dipole tag antenna using an artificial magnetic conductor (AMC) for wireless identification and a wireless identification system using the dipole tag antenna. The dipole tag antenna includes: a substrate formed of a first dielectric material; a conductive ground layer formed underneath the substrate; an AMC layer formed on the substrate; the dipole tag antenna mounted on the AMC layer and comprising a wireless identification chip; and the AMC directly mounted on a conductor.

Dipole tag antenna structure mountable on metallic objects using artificial magnetic conductor for wireless identification and wireless identification system using the dipole tag antenna structure

A multi-directional resonant-type electromagnetic wave absorber includes: at least one ground layer; a first dielectric layer and a second dielectric layer respectively formed on different outer surfaces of the ground layer; a first resistive pattern layer formed on an outer surface of the first dielectric layer; and a second resistive pattern layer formed on an outer surface of the second dielectric layer. Herein, the electromagnetic absorption performance is adjusted by changing one or more of thicknesses, permittivities, and permeabilities of the dielectric layers, thicknesses of the resistive pattern layers, and a reflection coefficient of the ground layer.

Multi-directional resonant-type electromagnetic wave absorber, method for adjusting electromagnetic wave absorption performance using the same and manufacturing method of the same

An electromagnetic absorber using resistive material includes a ground plane of a conductive material; a dielectric layer formed on the ground plane; and a pattern layer in which specific unit cell patterns made of a resistive material are periodically arranged on the dielectric layer. The electromagnetic absorber is applied to an electronic toll collection system, a transportation device, a building structure, an electronic device and an anechoic chamber.

Growing community of inventors

Daejeon, South Korea

Dong-Uk Sim