Abstract: Provided is a frame transmission method of interference alignment (IA) and controlling, the method including calculating a channel matrix of a basic service set (BSS) by measuring channel information between an access point and a user terminal, performing singular value decomposition (SVD) based on the calculated channel matrix, selecting a beamforming vector in consideration of an interference amount associated with another access point based on the SVD performed by the channel matrix, and calculating a leakage interference (LIF) value based on the selected beamforming vector.

Abstract: Provided is a frame transmission method of interference alignment (IA) and controlling, the method including calculating a channel matrix of a basic service set (BSS) by measuring channel information between an access point and a user terminal, performing singular value decomposition (SVD) based on the calculated channel matrix, selecting a beamforming vector in consideration of an interference amount associated with another access point based on the SVD performed by the channel matrix, and calculating a leakage interference (LIF) value based on the selected beamforming vector.

Abstract: Provided is a frame transmission method of interference alignment (IA) and controlling, the method including calculating a channel matrix of a basic service set (BSS) by measuring channel information between an access point and a user terminal, performing singular value decomposition (SVD) based on the calculated channel matrix, selecting a beamforming vector in consideration of an interference amount associated with another access point based on the SVD performed by the channel matrix, and calculating a leakage interference (LIF) value based on the selected beamforming vector.

Abstract: A communication system configured to send data using an interference alignment scheme is disclosed herein. The disclosed communication system includes an MS and a BS. The disclosed BS sends data using a transmission beamforming matrix that minimizes intra-cell interference. The disclosed MS receives the data using a reception beamforming matrix that minimizes inter-cell interference. The BS sends information about a reference beamforming matrix to the MS, and sends a pilot signal to the MS using the reference beamforming matrix. The MS estimates an effective channel using the reference beamforming matrix, and calculates the intensity of an interference signal from an interference BS.

Abstract: Provided is a frame transmission method of interference alignment (IA) and controlling, the method including calculating a channel matrix of a basic service set (BSS) by measuring channel information between an access point and a user terminal, performing singular value decomposition (SVD) based on the calculated channel matrix, selecting a beamforming vector in consideration of an interference amount associated with another access point based on the SVD performed by the channel matrix, and calculating a leakage interference (LIF) value based on the selected beamforming vector.

Abstract: A method for reducing inter-cell interference (ICI) in a mobile communication system controls transmission signal power of an uplink signal from a terminal based on signal power measurement for a signal received from a base station of a neighboring cell. A terminal receives a signal from a base station of a neighboring cell via a wireless channel, measures a channel response against a threshold value across an applicable frequency band by using the received signal, determines a transmission signal power for each frequency band used for data transmission based on the measured channel response, and transmits data to a home cell base station according to the transmission signal power for each frequency band. The terminal may measure a channel response based on signals received from multiple base stations in multiple neighboring cells, and may also evaluate signal power of a signal transmitted from the home cell.

Abstract: A method for controlling inter-cell interference (ICI) in a mobile communication system by transmitting uplink control information from a base station in a home cell to a terminal of a neighboring cell based on ICI amount information measured at the base station. The ICI control method includes receiving an uplink signal at a base station and extracting inter-cell interference amount information from the uplink signal, generating uplink control information based on the extracted inter-cell interference amount information, and transmitting the uplink control information to a terminal in a neighboring cell. The terminal schedules an uplink resource including selecting frequency bands for an uplink signal by referring to the uplink control information.

Abstract: A communication system configured to send data using an interference alignment scheme is disclosed herein. The disclosed communication system includes an MS and a BS. The disclosed BS sends data using a transmission beamforming matrix that minimizes intra-cell interference. The disclosed MS receives the data using a reception beamforming matrix that minimizes inter-cell interference. The BS sends information about a reference beamforming matrix to the MS, and sends a pilot signal to the MS using the reference beamforming matrix. The MS estimates an effective channel using the reference beamforming matrix, and calculates the intensity of an interference signal from an interference BS.

Abstract: A communication device includes an RF receiver that receives a combined signal including a first signal transmitted from a first node and a second signal transmitted from a second node, a channel estimator that estimates first channel information of the first signal and second channel information of the second signal, respectively, a multiuser detector that detects original signal values of the combined signal using the estimated first and second channel information and an RF transmitter that transmits a signal generated based on the values detected by the multiuser detector to the first node and the second node during a predetermined period.

Abstract: The invention relates to a data transfer method in a multi-hop relay system. The data transfer method comprises: a step for allowing a base station to receive from a first terminal the channel information (Hd,1) between the base station and the first mobile station, a step for making the base station generate an interference cancellation precoding matrix using Hd,1, a step for forcing the base station to transfer first data to a relay station, and a step for making the relay station transfer the first data to the first mobile station and forcing the base station to transfer second data to a second mobile station, wherein the second data is converted using the interference cancellation precoding matrix. According to the disclosed data transfer method in the multi-hope relay system, the base station transfers data to another mobile station efficiently when the relay station transfers data to a mobile station.

Abstract: A scheduler and scheduling method that may select a data transmission time interval and a data transmitting station are included in a multi-user Multiple Input Multiple Output (MIMO) communication system. An access point may include a receiver to receive channel measurement signals from stations using a plurality of receive antennas; a channel estimation unit to generate channel state matrices with respect to wireless channels formed from the stations to the receive antennas using the channel measurement signals; and a scheduler to select at least one transmitting station from the stations by considering the channel state matrices and a number of the receive antennas. The receiver may receive a data stream from the selected transmitting stations. Stations receive identifiers corresponding to transmitting stations and/or transmitting antennas to identify stations or antennas for transmitting data streams to the access point.

Abstract: A method for controlling the charging of segments for an online electric vehicle is described. In some situations, the method comprises: (a) receiving, from segments, information on the speed and position of the vehicle entering the range of the power-supplying device; and (b) controlling the charging/discharging timing of the current segment from which the vehicle is leaving and the next segment into the range of which the vehicle is to enter, in accordance with the information on the speed and position of the vehicle. The charging/discharging response delay characteristics of the segments may be considered.

Abstract: A method and apparatus for transmitting/receiving data in a communication system are provided, in which an MCS level is determined for data, a codeword including the data and a parity is generated by encoding the data using the determined MCS level, code symbols are generated from the codeword using IR scheme, and each of the code symbols is sent in a corresponding subframe.

Abstract: A scheduler and scheduling method that may select a data transmission time interval and a data transmitting station are included in a multi-user Multiple Input Multiple Output (MIMO) communication system. An access point may include a receiver to receive channel measurement signals from stations using a plurality of receive antennas; a channel estimation unit to generate channel state matrices with respect to wireless channels formed from the stations to the receive antennas using the channel measurement signals; and a scheduler to select at least one transmitting station from the stations by considering the channel state matrices and a number of the receive antennas. The receiver may receive a data stream from the selected transmitting stations. Stations receive identifiers corresponding to transmitting stations and/or transmitting antennas to identify stations or antennas for transmitting data streams to the access point.

Abstract: A multiple access digital communication method in ultra-wideband (UWB) radio access network is provided. More specifically, a multiple access technique in UWB communication channels is provided where UWB communication channels can be more efficiently used and collisions between multiple access user nodes can be more effectively avoided when the channels have a great multiple path fading. The digital communication method for use in an uplink in a UWB communication system includes the steps of: receiving data symbols from respective nodes, in which the data symbols are transmitted according to respective orthogonal time hopping patterns; checking whether there is a collision of the orthogonal time hopping patterns; and decoding the data symbols depending on whether data symbols of nodes involved in the collision of the orthogonal time hopping patterns are the same.

Abstract: An Ultra-Wideband (UWB) wireless communication system in a multi-user environment determines a threshold value to eliminate a signal pulse affected by a near-interference from among a plurality of signal pulses transmitted a number of times. A method for controlling an interference includes receiving the signal pulses, calculating a correlation value by applying a predetermined correlation mask to the signal pulses, determining a threshold value by referring to the number of times that the signal pulses are transmitted, a signal-to-interference-and-noise ratio, and information about a ratio of a near-interference to a far-interference, and eliminating signal pulses having a correlation value greater than the threshold value. The correlation values that are not greater than the threshold value are summed to detect a bit corresponding to each pulse signal.

Abstract: A method for controlling inter-cell interference (ICI) in a mobile communication system by transmitting uplink control information from a base station in a home cell to a terminal of a neighboring cell based on ICI amount information measured at the base station. The ICI control method includes receiving an uplink signal at a base station and extracting inter-cell interference amount information from the uplink signal, generating uplink control information based on the extracted inter-cell interference amount information, and transmitting the uplink control information to a terminal in a neighboring cell. The terminal schedules an uplink resource including selecting frequency bands for an uplink signal by referring to the uplink control information.

Abstract: A communication device includes an RF receiver that receives a combined signal including a first signal transmitted from a first node and a second signal transmitted from a second node, a channel estimator that estimates first channel information of the first signal and second channel information of the second signal, respectively, a multiuser detector that detects original signal values of the combined signal using the estimated first and second channel information and an RF transmitter that transmits a signal generated based on the values detected by the multiuser detector to the first node and the second node during a predetermined period.

Abstract: Provided is a communication system for ultra wide band impulse communication, and more particularly, to a communication apparatus and method that can be used in a sensor network or a low-rate wireless personal area network. To be more specific, the present research suggests a transmitter employing multi-coded bi-orthogonal pulse position modulation/demodulation and a method thereof.

Abstract: In a Multiple-Input Multiple-Output (MIMO) wireless local area network (WLAN) system, a method is provided for selecting at least one antenna from a plurality of antennas and transmitting a data frame from a station to an access point via the selected antenna or antennas. A method for transmitting data from a plurality of stations to an access point in the MIMO WLAN system includes detecting a channel status of a channel from the access point to each transmitting antenna of the station, selecting at least one transmitting antenna from among the station's transmitting antennas based on the detected channel status, and transmitting a data frame from the station to the access point via the selected transmitting antenna or antennas.