Electronics and Telecommunications Research Institute

Hee Soo Lee

Jae Young Ahn

Sok Kyu Lee

Kyoung Seok Lee

Tae Gyun Noh

Young Jo Ko

Il Gu Lee

Eun Kyung Kim

Min Ho Cheong

Hyun Jun Lee

Yu Ro Lee

Tae Joong Kim

Hee Jung Yu

Hyun Seo Park

An Seok Lee

Jung Bo Son

Nam Hoon Park

Seong Rag Kim

Chang Wahn Yu

Jae Kyun Kwon

Jeong Chul Shin

A reference signal (RS) transmission system to transmit a channel state information (CSI) RS for extraction of CSI to a relay and a macro terminal is disclosed. The base station transmits information on a sub frame containing the CSI RS to the relay or the macro terminal. The macro terminal and the relay receive the CSI RS using the information on the sub frame. The macro terminal and the relay extract the CSI using the CSI RS and transmit the extracted CSI to the base station.

System for transmitting reference signal with information on state of channel

Provided are an uplink transmission method and downlink transmission method in a mobile communication network including a relay. In the uplink and downlink transmission methods, frame structures and transmission timings of a backhaul downlink and a backhaul uplink are determined in consideration of at least one of a time for the relay to switch between transmission and reception and a signal transmission time. Accordingly, in a wireless communication system including a relay, it is possible to effectively perform data transmission and reception between the relay and a base station.

Data transmission method for wireless communication system involving relay

An operation method of a terminal, for a handover in a mobile communication system, may comprise performing measurement on beams of a target base station, and transmitting a measurement result of at least one beam of the target base station to a source base station; receiving, from the source base station, a handover command message including information on at least one RACH resource for the at least one beam; transmitting a handover indication message including information on at least one random access target beam having an order of channel conditions determined based on a latest measurement to the source base station and to the target base station through the source base station; and determining an optimal beam among the at least one random access target beam, and transmitting a RACH to the target base station through a RACH resource allocated to the optimal beam.

Handover method in mobile communication system

An operation method of a terminal includes receiving configuration information from a serving base station; measuring channel states of the serving base station and a target base station; when a difference between received signal strengths of the serving base station and the target base station is not less than a handover preparation offset, determining that a handover preparation event has occurred and transmitting a measurement report message to the serving base station; and when the difference is equal to or greater than a handover execution offset, determining that a handover execution event has occurred and transmitting a handover indication message informing of execution of a handover to the target base station. The channel state is normal state, abnormal state, or RLF state, and the configuration information indicates a different handover preparation offset and a different handover execution event according to the channel state.

Communication node for performing handover in wireless communication system and method therefor

A method and apparatus for estimating a channel in a wireless local area network (WLAN) are provided. A channel estimation apparatus may include a channel estimation information combiner to combine at least one channel estimation information based on a difference between cyclic delay diversity (CDD) values, and a phase applier to generate a first phase value and to apply the first phase value to the combined channel estimation information.

Apparatus and method for estimating channel in wireless local area network (WLAN) system

A multi-channel low power communication method and apparatus are provided. The multi-channel low power communication method may include transmitting request to send (RTS) to a receiver through a plurality of communication channels, receiving clear to send (CTS) from the receiver in response to the RTS, and transmitting a data packet through part or entire of at least one communication channel having received the CTS among the plurality of communication channels, wherein at least one of the RTS and the CTS comprises a multi-channel power save information field related to multi-channel power save.

Multi-channel low power communication method and apparatus

Disclosed are an access point apparatus for configuring a next generation wireless communication and a method of operating the access point apparatus. The access point apparatus for configuring the next generation wireless communication may include a verification unit to verify a first available band associated with at least one of a first band and a second band; and a configuration unit to configure a backbone network with another access point apparatus positioned within a predetermined distance, through the verified first available band.

Access point apparatus for configuring next generation wireless communication network and method of operating the access point apparatus

Disclosed are a terminal and a base station for a distributed array massive multiple-input and multiple-output (MIMO) communication antenna system and an operation method thereof, wherein the terminal includes a distribution analog unit receiving a plurality of analog array receive signals based on a terminal antenna transmit signal from a virtual terminal through a plurality of distributed antenna arrays and a digital unit restoring the terminal antenna transmit signal based on the analog array receive signals and a channel parameter, and the base station includes an antenna receiving an analog receive signal based on a transmit beamforming input signal from a plurality of distributed antenna arrays, a virtual terminal restoring the transmit beamforming input signal based on an amplitude of the analog receive signal, and a terminal receive signal mapper mapping the transmit beamforming input signal to a base station transmit signal.

Base station and terminal for distributed array massive multiple-input and multiple-output (MIMO) communication antenna system

A physical layer low power communication method and apparatus are provided. The physical layer low power communication method may include receiving a data packet from a transmitter, measuring a channel quality using a preamble and signal field information included in the data packet and determining whether recovery of the data packet is possible, calculating an error generation rate according to a determination result, and discarding the data packet and operating in a power save mode when the error generation rate is higher than a predetermined reference.

Physical layer low power communication method and apparatus

Disclosed is a method for controlling interference in a heterogeneous network environment. The method for controlling the inter-cell interference of a base station according to one aspect of the present invention comprises the following steps: transmitting, to a terminal, information relating to subframes in which a portion of a resource is to be punctured; transmitting, to the terminal, a relevant subframe in which a portion of a resource is punctured on the basis of the information relating to said subframes. A method for controlling the inter-cell interference of a base station according to another aspect of the present invention comprises the following steps: setting a resource for transmitting system information; and transmitting system information using only said resource for transmitting system information, or preferentially using said resource for transmitting system information when transmitting system information using a subframe designated as an almost blank subframe (ABS). Accordingly, inter-cell interference problems may be alleviated even in the event pieces of important system information, such as CRS, should be transmitted using an ABS.

Method for controlling interference in an overlaid network environment

A method for managing neighbor cell interference comprises: a step of measuring inter-cell interference control information by subframe units; and a step of transmitting the inter-cell interference control information measured by subframe units, to at least one neighbor cell for each of the subframes. The interference management method of the present invention dynamically performs neighbor cell interference management under the condition where neighbor cell interference changes in terms of time, thus improving performance of a system. Further, the interference management method of the present invention maps a wireless resource property pattern to a cell ID. Consequently, the system adopting the method of the present invention exhibits excellent performance in any environment.

Growing community of inventors

Daejeon, South Korea

Hee Soo Lee