Electronics and Telecommunications Research Institute

University-Industry Cooperation Group of Kyung Hee University

Gwangzeen Ko

Chang-Joo Kim

Myung-Sun Song

Sung-Hyun Hwang

Sang-Won Kim

Myung Sun Song

Jung-Sun Um

Seong-Min Kim

In Kui Cho

Jung Ick Moon

Sung-Jin You

Je Hoon Yun

Jung Sun Um

Moon-Won Lee

Sung Hyun Hwang

Igor Kim

Chang Joo Kim

Jinhyung Oh

Sunmin Lim

Changhyun Park

Woo Jin Byun

Chung-Gu Kang

Dong Won Jang

Yun-Hee Kim

Young Chai Ko

Hyun Ho Lee

Hoiyoon Jung

Duk Ju Ahn

Yun Hee Kim

Sung Jin You

Min-Sheo Choi

Bub-Joo Kang

Myeong Jin Kim

Il-Hwan Kim

Saidul Alam Chowdhury

Shahid Ali Khan

Jung-Sun 408-205 Jugong-4Danji Apt 908 Um

Provided is a wireless power reception apparatus. The wireless power reception apparatus includes a resonant circuit including a first path and a second path, the first path including a first capacitor and a first gate connected in series, and the second path being connected in parallel with the first path and including a second capacitor and a second gate connected in series and a reception coil connected to the resonant circuit, configured to wirelessly receive power based on a capacitance of the resonant circuit, and to generate power according to the wirelessly received power, wherein the resonant circuit is configured to determine a gate driving signal to operate the first gate and the second gate and wherein the capacitance of the resonant circuit is determined according to the gate driving signal.

Wireless power reception apparatus

An image processing-based foreign substance detection method in a wireless charging system and a device performing the method are disclosed. A method for detecting a foreign substance includes an operation of acquiring an image of a charging area of a wireless charging system, an operation of detecting, based on an RGB value of a frame of the image, a foreign substance in the charging area, an operation of discriminating a type of the foreign substance, and an operation of performing power control of the wireless charging system according to the type of the foreign substance.

Image processing-based foreign substance detection method in wireless charging system and device performing method

A wireless power transmission resonator using a conducting wire with a vertical rectangular cross-section is disclosed. The wireless power transmission resonator may include a first element including a first element upper part arranged in an upper end of a resonator and a first element lower part arranged in a lower end of the resonator, wherein the first element upper part and the first element lower part each may include a spiral layer having a spiral structure that is wound to face a wide surface of a conducting wire including a vertical rectangular cross-section and a second element arranged in a center of the resonator and between the first element upper part and the first element lower part and including a spiral layer having a spiral structure that is wound to face the wide surface of the conducting wire including the vertical rectangular cross-section.

Wireless power transmission resonator using conducting wire with vertical rectangular cross-section

Provided is a spiral coil and wireless power transmission and reception circuit including the spiral coil. The spiral coil includes a conducting wire forming one or more coil turns, and a height of one side of the conducting wire in a direction of a central portion of the spiral coil and a height of another side of the conducting wire in an opposite direction to the central portion of the spiral coil in each of the coil turns are different from each other and the conducting wire includes at least one slot formed by an empty space between the one side and the other side, and an upper surface positioned above the one side and the other side and connecting the one side and the other side.

Spiral coil and wireless power transmission and reception circuit including the same

An interference alignment method using multiple antennas in a multi-cell overlapped environment, includes: when at least one transmission and reception ends having at least one or more antennas communicate with each other, establishing at least one or more channels from the transmission end to the reception end. Further, the interference alignment method includes designing a processing filter for a transmission signal transmitted from the transmission end to the reception ends; and designing a processing filter for a reception signal that is received by the reception end.

Method for interference alignment using multiple antennas in overlapped multi-cell overlapped environment

Disclosed is a method for removing signal interference in a MIMO-based interference removing apparatus including transmitting a reference signal to at least one receiver; if channel information is estimated by the receiver, receiving the estimated channel information from the receiver as a feedback signal; and producing transmission pre-coding matrix, beam forming matrix, and weighted matrix using the received channel information. Further, the method includes transmitting information containing the transmission pre-coding matrix, the beam forming matrix, and the weighted matrix by including them in a pilot signal to the receiver, and the MIMO-based interference removing apparatus comprises at least one transmitter.

Method for removing signal interference based on multiple input multiple output

A method and an apparatus for controlling transmit power of a CR device are provided. The method includes acquiring CR environment information regarding a licensed user or an unlicensed user occupying an adjacent channel or an adjacent cell of the CR device; determining a transmit power value of the CR device using the CR environment information; and generating transmit power control information including the transmit power value. The method and apparatus guarantee reliable communication of the CR device and minimize interference with the licensed user.

Transmission power control method and device for cognitive radio device

Provided is a hybrid beaconing method in which a centralized beaconing scheme and a distributed beaconing scheme are combined. In the hybrid beaconing method, a beaconing scheme is converted according to a network condition, and a centralized beaconing scheme or a distributed beaconing scheme is used to maintain an optimum network status.

Hybrid beaconing method

Provided is a large range management device (LRMD) of managing a communication between a plurality of small range devices (SRDs) and a plurality of large range devices (LRDs), the SRDs and the LRDs being located in a single cell and having different transmission coverage, the LRMD including an access slot allocation unit to allocate an SRD access slot to a radio resource for a downlink, to enable a first SRD to request an association from a network, a selection unit to select a communication relay device for relaying relay data of the first SRD, a relay slot allocation unit to allocate at least one SRD relay slot to a radio resource for an uplink, to enable the communication relay device to relay the relay data to a second SRD or another LRD, and a receiving unit to receive the relay data based on the at least one SRD relay slot.

Method and device for communication between devices with different transmission coverage

Provided is a method and apparatus for efficiently transmitting and receiving a frame including a header and a payload in a communication system. If the number of repeated items in the content of a header of the frame is high, specific preambles are allocated to the repeated items and the repeated items are omitted. Accordingly, data transfer efficiency can be improved.

Method and apparatus for compressing frame

Provided are a method of adaptively allocating appropriate hybrid bursts according to terminal attributes including terminal position, channel state, and service type in an orthogonal frequency-division multiple access (OFDMA) system, and an upstream-MAP information element (US-MAP IE) structure supporting the method. The method includes dividing an upstream subframe into a plurality of zones depending on the number of OFDMA symbols and allocating bursts of a zone to a terminal according to the terminal attributes. Bursts are formed by allocating slots along a time axis in the upstream subframe, and are formed by allocating slots along a frequency axis in a downstream subframe.

Method and apparatus of hybrid burst mapping in OFDMA systems

Provided are methods of spectrum sensing and assigning quiet periods in a cognitive radio system in order to increase the reliability of detection regarding whether an incumbent user appears in his/her frequency channel, customer premises equipment (CPE), a base station, and the structure of a super frame for performing the methods. The spectrum sensing method includes communicating with a base station (BS) and performing spectrum sensing for frequency channels having quiet periods (QPs) during the QPs of the frequency channels used in the cognitive radio system, wherein the QPs of the frequency channels do not overlap each other

Method for sensing spectrum and arranging quiet period in cognitive radio system, customer premise equipment, base station and superframe structure using the same

A resource reservation method between a master device and a slave device or between slave devices in a centralized network. In resource reservation between slave devices, optimal resources may be allocated by performing link measurement between the slave devices before allocating the resources.

Reserving resources in centralized network by scanning superframes equal to or greater than maximum number of superframes allowed without listening to beacon period

A method and apparatus for detecting a signal using a cyclo-stationary characteristic value is provided. A method of detecting a signal using a cyclo-stationary characteristic value includes: calculating cyclo-stationary characteristic values with respect to a cyclic frequency domain of an input signal; multiplying the calculated cyclo-stationary characteristic values with each other; and detecting the signal from the input signal based on the result of the multiplication.

Method and apparatus for detecting signal using cyclo-stationary characterisitics

A channel switching method is provided for a base station to allocate a slot for data exchange with each of a plurality of terminals in a frequency channel that is not used by an incumbent user (IU). The method includes include transmitting a channel switching message for requesting to switch to a backup channel when a signal of the IU is sensed in the frequency channel; transmitting a beacon frame via the backup channel, wherein the beacon frame comprises allocation information about slots which are in the frequency channel and which are respectively allocated to each of the plurality of terminals; and allocating the slot for data exchange with each of the plurality of terminals to the backup channel according to the allocation information, and communicating with each of the plurality of terminals.

Growing community of inventors

Daejeon, South Korea

Gwangzeen Ko