Samsung Electronics Co., Ltd.

Information and Communications University, Research and Industrial Cooperation Group

Chung Ang University Industry Academic Cooperation

Research & Industrial Cooperation Group

Icu Research Industrial Cooperation Group

Young-Hoon Kwon

Sang-Boh Yun

Soon-Young Yoon

Sung-Soo Hwang

Joo-Hyun Lee

Jang-Hoon Yang

Soong-Yoon Choi

Jae-Hee Cho

In-Seok Hwang

Hyun-Cheol Park

Kyung-Joo Suh

Keun-Chul Hwang

Hyoun-Kuk Kim

Yong-Seok Kim

Sung-woo Park

Ki-Young Han

Sang-Hoon Sung

Suk-Seung Hwang

Jong-Ho Lee

June Moon

Dong-Ho Cho

Ki-Ho Lee

Hoon Huh

Sung-Yoon Jung

Chi-Hyun Park

Heon-Ki Chae

Oh-Soon Shin

Chi-Sung Bae

Soo-Yong Jeon

Ki-Hwan Jeon

Jong-Wuk Son

Jong-in Kim

Jong-Hyeuk Lee

Jong-In Kim

Yong-Soo Cho

Jin-Ghoo Choi

Won-Suk Choi

Jae-Kwon Kim

Tae-Ho Im

Eun-Sun Choi

Won-Kyun Suk

Soon-Yoon Yoon

An apparatus and method for performing distributed spatial multiplexing and distributed spatial diversity in a multi-hop relay system are provided. In the multi-hop relay system, a transmitter includes an outer coder for performing outer coding on transmission data, an outer interleaver for interleaving data received from the outer coder, an inner coder for dividing data received from the outer interleaver into a plurality of frames and performing inner coding on the divided frames, and a transmitting unit for transmitting hierarchically coded frames received from the inner coder to respective Relay Stations (RSs).

Apparatus and method for supporting distributed spatial multiplexing and distributed spatial diversity in multi-hop relay system

A resource allocation in a broadband wireless communication system is provided. An apparatus for a base station in a broadband wireless communication system includes a manager for managing resources by dividing the resources into a plurality of regions based on a maximum supportable error vector magnitude (EVM) in a frequency axis; and an allocator for allocating resources of a region other than a first region, the region having the smallest maximum supportable EVM, to a service to which a maximum modulation and coding scheme (MCS) level is not applied.

Apparatus and method for allocating resources based on error vector magnitude (EVM) in a broadband wireless communication system

An apparatus and method for location estimation in a wireless communication system are provided. The method includes identifying if a received at least one signal passed through at least one repeater, when the received at least one signal is identified as having passed through at least one repeater, measuring a Base Station (BS) basis delay time and calculating a repeater basis delay time using the measured BS basis delay time, and estimating a location of the Mobile Station (MS) using the repeater basis delay time.

Apparatus and method for location estimation in a wireless communication system

An apparatus and a method are provided for detecting N number of TX signals in a MIMO wireless communication system. The apparatus includes an RF processor, a channel estimator, and a signal detector. The RF processor converts signals, received through multiple antennas, into baseband signals. The channel estimator estimates channel information of the respective antennas by using the received signals. The signal detector arranges the baseband signals of the respective antennas on the basis of the channel information, calculates a threshold value of each stage, and selects symbols with a cumulative metric smaller than or equal to the threshold value as candidates at each stage, to detect a TX signal vector with N number of symbols.

Apparatus and method for detecting signal based on QR-decomposition in multiple input multiple output wireless communication system

A signal reception apparatus of an orthogonal frequency division multiplexing (OFDM) communication system using a multiple input, multiple output (MIMO) scheme. The signal reception apparatus, when it uses the Nreceive antennas, receives a time-domain preamble signal transmitted by a signal transmission apparatus corresponding thereto via each of the Nreceive antennas, and estimates a channel according to a channel estimation scheme using the time-domain preamble signal received via each of the Nreceive antennas. When the signal transmission apparatus uses Ntransmit antennas, the time-domain preamble signal is a signal transmitted by the signal transmission apparatus via each of the Ntransmit antennas for a second time period which is set according to a corresponding transmit antenna within a first time period.

Apparatus and method for transmitting/receiving preamble signal and estimating channel in an orthogonal frequency division multiplexing communication systems using multiple input multiple output scheme

An apparatus and method for improving the reception performance of a Mobile Station (MS) in a multiple antenna system are provided. In an apparatus of a Base Station (BS) in the multiple antenna system, upon receipt of a request for interference cancellation for a first MS serviced by a neighbor BS, a channel estimator estimates a channel from the first MS and a channel from a second MS serviced by the BS. A beam coefficient generator generates a first beam coefficient based on channel estimates of the first and second MSs and a second beam coefficient based on the channel estimate of the second MS. An interference cancellation decider determines whether to perform interference cancellation for the first MS using the first and second beam coefficients.

Apparatus and method for improving reception performance in a smart antenna system

A method and apparatus for removing interference from a UpLink (UL) signal in a Time Division Duplex (TDD) system are provided. The method includes determining whether a section for receiving an UpLink (UL) signal from the MS overlaps with sections for sending a DownLink (DL) signal of neighbor BSs in service, the neighbor BSs sending the DL signal to another MS, when the UL signal section overlaps with the DL sections of the neighbor BSs, detecting DL transmit signal information from the neighbor BSs transmitting in the overlapping sections, and removing interference from the UL signal using the detected transmit signal information. Accordingly, the accuracy of detecting the signal from the MS can be raised without having to adopt the complex resource allocation scheme to avoid the interference of the neighbor BSs.

Method and apparatus for removing interference from uplink signal in Time Division Duplex (TDD) system

An apparatus and method for lowering a tree searching complexity in a Spatial Multiplexing (SM) Multiple Input Multiple Output (MIMO) antenna system are provided. A transmitting apparatus includes a generator for generating a plurality of transmit streams by spatial-multiplexing a transmit data, a determiner for determining modulation schemes to be applied to the plurality of the transmit streams respectively and a modulator for modulating the plurality of the transmit streams using at least two modulation schemes under control of the determiner. The receiver detects the signals by allocating the modulation scheme of the lowest order to the upper tree level.

Detection complexity reducing apparatus and method in multiple input multiple output (MIMO) antenna system

An apparatus and method for location estimation in a wireless communication system are provided. The method includes identifying if a received at least one signal passed through at least one repeater, when the received at least one signal is identified as having passed though at least one repeater, measuring a Base Station (BS) basis delay time and calculating a repeater basis delay time using the measured BS basis delay time, and estimating a location of the MS using the repeater basis delay time.

A partial iterative detection and decoding apparatus in a Multiple Input Multiple Output (MIMO) system includes a detector for detecting signals received through at least one receive antenna to generate a first soft decision value, a decoder for decoding the first soft decision value to generate a second soft decision value, and a reliability determiner for determining a signal to be iteratively detected and decoded by using the second soft decision value. Accordingly, the complexity of the receiver is reduced and the number of iterations limited due to the complexity is increased, thereby improving the performance of the receiver.

Partial iterative detection and decoding apparatus and method in MIMO system

An iterative detection and decoding method in a Multiple Input Multiple Output (MIMO) system includes detecting entire MIMO nodes to generate soft decision values; decoding a first soft decision value among the soft decision values; determining whether to perform an iterative detection and decoding by measuring reliability of the decoded first decoding signal; generating a soft decision value by performing a redetection of a MIMO node containing the soft decision value, when the decoded soft decision value is iteratively detected and decoded; and decoding a second soft decision value among the soft decision values.

Iterative detection and decoding apparatus and method in MIMO system

A method and apparatus for detecting a signal in a communication system using at least two transmit antennas are provided. The signal detection method and apparatus includes selecting a symbol corresponding to a lowest branch metric from among symbols, the number of which corresponds to a modulation scheme, determining a candidate symbol by extending a process of selecting a symbol corresponding to a lowest branch metric from among the selected symbols, to a number which is less by one than the number of the transmit antennas, setting an accumulated branch metric of the candidate symbol as a threshold, removing a symbol having an accumulated branch metric higher than the threshold, and selecting, as a last received symbol, a symbol corresponding to a path having the lowest accumulated branch metric among paths selected without being removed until a last stage.

Apparatus and method for detecting a signal in a communication system using multiple antennas

Receiving apparatus and method in a Multiple-Input Multiple-Output (MIMO) wireless communication system are provided. The receiver having N-ary receive antennas includes a decomposer for decomposing a channel matrix to a matrix Q and a matrix R through a QR decomposition; a detector for determining a candidate group of an n-th phase by estimating a plurality of transmit signal vectors by substituting a plurality of transmittable symbols into symbol combinations of a candidate group of a (n&#x2212;1)-th phase as an n-th symbol and detecting (n+1)-th through N-th symbols using characteristics of the matrix R; a calculator for calculating square Euclidean distance values between the transmit signal vectors and a receive signal vector; and a determiner for determining the candidate group of the n-th phase by selecting transmit signal vectors having the smallest square Euclidean distance value among the transmit signal vectors.

Apparatus and method for detecting signal in multiple-input multiple-output (MIMO) wireless communication system

An apparatus and method for detecting a signal in a receiver by maximum likelihood (ML) are provided, in which symbols are detected according to the number of transmit antennas of a transmitter and a modulation scheme, channels are estimated, an equivalent channel matrix corresponding to the estimated channels is determined, a permuted equivalent channel matrix is determined by multiplying the equivalent channel matrix by a predetermined permutation matrix, the permuted equivalent channel matrix is QR decomposed, a hard decision is performed on predetermined symbols among the detected symbols using a received signal resulting from the QR decomposition, and the log likelihood ratios (LLRs) of the hard-decided symbols are determined.

Apparatus and method for detecting signal by maximum likelihood

Provided are an ARQ apparatus and method for a multihop system in a broadband wireless access communication system. The ARQ method of a relay includes determining if the relay successfully receives specific data from a source and transmitting the specific data to a destination; receiving feedback data from the destination and determining if the destination successfully receives the specific data; generating feedback data including data indicating if the relay and the destination successfully receive the specific data, and outputting the feedback data to the source; and retransmitting the specific data, when the relay successfully receives the specific data but the destination fails to receive the specific data. Accordingly, when the MH-BTS successfully receives the data from the source but the destination fails to receive the data, the source does not retransmit same data to the MH-BTS.

Automatic request apparatus and method for multihop system in broadband wireless access communication network

Growing community of inventors

Seongnam-si, South Korea

Young-Hoon Kwon