Samsung Electronics Co., Ltd.

University of Texas System

Alcatel Lucent

Yonsei University

Seoul National University

Chan-Byoung Chae

Hong-Sil Jeong

Dong-seek Park

Won-Il Roh

Chang-Ho Suh

Sung-ryul Yun

Jeong-Tae Oh

Kyun-Byoung Ko

Jae-Yoel Kim

Young-Kwon Cho

Robert Wendell Heath, Jr

Pan-Yuh Joo

Jung-Min Ro

Katz Marcos Daniel

Jong-Hyung Kwun

Seok-Hyun Yoon

Seung-Joo Maeng

Jae-Ho Jeon

Jae-Hak Chung

Seung-Hoon Nam

Byoung-Yun Kim

Ho-Kyu Choi

Young-Ho Jung

Sung-Ryul Yun

Chan-Soo Hwang

David Mazzarese

Youn-Sun Kim

Hyoung-Ju Ji

Hyo-Jin Lee

Young-Woo Kwak

Doru Calin

In-Soo Hwang

Dong-Seek Park

Kai Yang

Simon Yiu

Hyoung-Youl Yu

Jae-Am Choi

Marcos Daniel Katz

In-Bum Chang

Yeon-Geun Lim

Sung-Jin Kim

Kathiravetpillai Sivanesan

Do-Young Kim

Young-soo Park

Su-Ryong Jeong

Ho-Jin Kim

Hyeon-Woo Lee

Hongseok Kim

Sung-hyun Cho

Eun-Seok Ko

Ki-ho Kim

Denis Rouffet

Myung-Kwang Byun

Geun-Ho Lee

Sung-Kwon Hong

Kwang-Bok Lee

Ki-Ho Cho

Soong-Yoon Choi

Young-Kyun Kim

Sang-hyun Kim

Eun Seok Ko

Seok Hyun Yoon

Hyoung-Woon Park

Sei-Joon Shim

Sung-Bum Kim

Gustavo De Veciana

Taiwen Tang

Mazzarese David

Gun-Chul Hwang

Mikael Bergholz Knudsen

Gert Frølund Pedersen

Patrick Claus Friedrich Eggers

Katz-Marcos Daniel

Min Soo Sim

Won-Ii Roh

Sung-Ryul 811-806 Byeokjeokgol Yun

Chang-Hu Suh

Jae-Yoel 1601-435 Samsung Raemian Apt Kim

Example embodiments are directed to methods of reducing interference in a communication system. In at least one example embodiment, a method includes first determining, by a first transmitter having a multi-directional antenna configured to produce a plurality of beams, at least one interference level of at least one interfering beam of a plurality of beams of at least one transmitter in the communication system, second determining a transmitting beam pattern based on the interference level, the transmitting beam pattern indicating a sequence of illuminating the plurality of beams at corresponding time slots, third determining a fractional frequency reuse pattern based on the transmitting beam pattern, and transmitting data based on the transmitting beam pattern and the frequency reuse pattern.

Methods for reducing interference in a communication system

A method and apparatus for a channel feedback by a signal transmitting device in a Multiple Input Multiple Output (MIMO) system are provided. The method includes transmitting a pilot in which a compression rate is reflected to a signal receiving device; receiving channel related information on a compressed channel from the signal receiving device; and performing a precoding based on the channel related information. The apparatus includes a transmitting unit configured to transmit a pilot to which a compression rate is reflected to a signal receiving device; a receiving unit configured to receive channel related information on a compressed channel from the signal receiving device; and a precoding unit configured to perform a precoding based on the channel related information.

Apparatus and method for channel feedback in multiple input multiple output system

An apparatus and a method for feeding a channel back in a wireless communication system using multiple input multiple output antennas (MIMO) are provided. The method includes receiving a signal from a transmitter and configuring a channel matrix for the received signal, configuring a basis transformed sparse channel using a sparsifying basis function with respect to the channel matrix, selecting a channel part to be fed back to the transmitter from the transformed sparse channel, and creating a codebook by quantizing the selected channel part, and feeding a codebook index corresponding to the created codebook back to the transmitter.

Example embodiments are directed to methods of reducing interference in a communication system. A method includes receiving, by a transmitter, first and second quantized matrices from a mobile station. The first and second quantized matrices are based on an estimated channel matrix and an estimated interference matrix. The method further includes determining, by the transmitter, a transmission beamforming vector based on the first and second quantized values.

Methods for reducing interference in communication systems

Examples are generally described that include methods for selecting a transmit mode in a communications system. An example method may include calculating a first transmission rate for data in a multiple-input multiple-output mode of the communications system and calculating a second transmission rate for the data in a single-input multiple-output mode of the communications system. A mode may be selected from the group consisting of the multiple-input multiple-output mode and the single-input multiple-output mode based, at least in part, on an energy consumption of the first and second transmission rates. Data may be transmitted from a transceiver in the communications system using the selected mode.

Methods and communication systems having adaptive mode selection

An apparatus and method are provided for beamforming in a MIMO wireless communication system. A base station includes a first calculator that repeatedly calculates downlink beamforming vectors of the user terminals to calculate the optimal beamforming vectors for the user terminals, a quantizer that quantizes the downlink beamforming vectors in order to transmit information of the downlink beamforming vectors, a control channel transmitter that feeds forward information of the quantized downlink beamforming vectors to the user terminals, a second calculator that calculates the final downlink beamforming vectors of the user terminals, and a beamforming transmitter that sums the beamformed TX signals of the user terminals and transmits the summed TX signals through a plurality of TX antennas.

Apparatus and method for beamforming with limited feedforward channel in multiple input multiple output wireless communication system

A base station is capable of transmitting a signal in a wireless communication network. The base station decides channel state information matrices of respective channels by determining a state of the channels corresponding to respective transmission antennas. The base station calculates transmission beam forming vectors for the respective transmission antennas by a combination of a dot product and a cross product of the channel state information matrices. Thereafter, the base station beam-forms signals for the respective transmission antennas by using the respective transmission beam forming vectors, and transmitting the beam-formed signals.

Method and apparatus for beam-forming signal in multi user-MIMO wireless communication system

A precoder and a precoding method in a multiuser multi-antenna system are provided. The precoder includes a channel checker for determining a DownLink (DL) channel condition of terminals in a service coverage area, a pre-compensator for pre-compensating, for channel distortion, signals to be sent to the terminals when a nonlinear algorithm is selected based on the channel condition of the terminals, and an interference remover for canceling interference in a channel by multiplying the pre-compensated signals by inverse channels of the terminals, and for canceling interference between the terminals. Accordingly, the pre-equalization can be carried out without global channel state information, and an increase of the transmit power can be prevented in the permutation.

Precoder and precoding method in a multi-antenna system

A method for beamforming by a transmission device in a multiantenna multiuser communication system. The method includes grouping codebook indexes included in a codebook into codebook index combinations, and calculating a sum of transmission rate for each of the codebook index combinations; selecting a codebook index combination with a maximum sum of transmission rate as an optimal codebook index combination; and transmitting a codebook index corresponding to a particular reception device among codebook indexes included in the optimal codebook index combination, to the particular reception device.

Apparatus and method for beamforming in a multiantenna multiuser communication system

An apparatus and method for beamforming in a Multiple Input Multiple Output (MIMO) wireless communication system are provided. A Base Station (BS) includes a calculator for generating relational expressions between beamforming vectors of Mobile Stations (MSs) using channel information of each MS, for determining beamforming vector candidates of each MS from the relational expressions using generalized Eigen-analysis, and for selecting beamforming vectors for each MS from the beamforming vector candidates, and a plurality of Transmit (Tx) beamformers for performing Tx beamforming on dedicated pilot symbols to be transmitted to each MS using the beamforming vectors for each MS.

Apparatus and method for beamforming based on generalized eigen-analysis in multiple input multiple output wireless communication system

A multiple antenna system for using a relay station with multiple antennas is provided. The system includes a base station for determining encoded data processing procedure based on first and second channel state information, determining a relaying procedure of the relay station, and sending the relaying procedure to the relay station based on the first and second channel state information; wherein the encoded data is terminating to a mobile station; the relay station for receiving data and the relay procedure which the base station sent, converting and sending the data according to the relaying procedure, and sending the first channel state information to the base station as a measured state of channel which receives the data; and the mobile station for receiving the data which the relay station sent, and sending the second channel state information to the relay station as a measured state of channel which receives the data.

Apparatus and method for transmission and reception in multiple input multiple output system with relay station

A transmitter in a multiple input multiple output (MIMO) communication system is provided. The transmitter includes a multiplexer for multiplexing an input bit stream into a plurality of bit streams, and outputting the bit streams in parallel; a bit-order rearranger for reordering bits constituting the bit streams, which are output from the multiplexer in the same time period, and outputting the reordered bits as reordered bit streams; and a modulator for modulating the parallel reordered bit streams output from the bit-order rearranger according to their associated modulation schemes, and transmitting the modulated symbols via their associated antennas.

Transmission apparatus and method for MIMO system

Provided is an apparatus and method for transmitting/receiving data in a multi-user multi-antenna communication system. A data transmitting apparatus and method computes a RX filter or a TX filter for each user receiver in an improved scheme, selects a codebook correlating with the computed TX filter or the computed RX filter, and transmits an index of the selected TX filter codebook or an index of the selected RX filter codebook to a receiver. A data receiving apparatus and method receives the codebook index and detects a corresponding RX filter from the codebook by using the received codebook index.

Apparatus and method for transmitting/receiving data in multi-user multi-antenna communication system

An apparatus and method for selecting at least two users to be serviced in SDMA in an SDMA wireless communication system are provided. All users are ordered according to a predetermined rule and all possible user combinations each having at least two users are created from the ordered users. An investigation limit number is set using the capacity of a juser combination. Or a total investigation number is reduced by comparing the interference-reflected SNR decrements of users with an investigation threshold. Therefore, the computation volume for selecting SDMA users is decreased.

User selection apparatus and method for SDMA in a MIMO system

A method and system for transmitting reference signals in a BWA communication system using a first transmit antenna, a second transmit antenna, and a plurality of sub-carriers. Each of the sub-carriers occupies a sub-frequency domain. In the method, reference signals for identifying a first transmit antenna are transmitted through a second predetermined number of sub-carriers in a first mini sub-channel transmitted through the first transmit antenna and occupied by a predetermined time domain and sub-frequency domains of a first predetermined number of sub-carriers, and reference signals for identifying a second transmit antenna are transmitted through the second predetermined number of the sub-carriers in a second mini sub-channel transmitted through the second transmit antenna and occupied by the time domain and the sub-frequency domains of the first predetermined number of sub-carriers.

Apparatus and method for transmitting pilot signal in a BWA communication system using transmit antennas

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Seoul, South Korea

Chan-Byoung Chae