Electronics and Telecommunications Research Institute

Samsung Electronics Co., Ltd.

Kt Corporation

Sk Telecom Company, Ltd.

Hanaro Telecom., Inc.

Ktfreetel Co., Ltd

Yonsei University

Southeast University

Dong-Seung Kwon

Yu-Ro Lee

In-Kyeong Choi

Seung-Joon Lee

Jong-Ee Oh

Seong-Rag Kim

Hyoung-Soo Lim

Choong-Il Yeh

Young-Seog Song

Chung-Yong Lee

Kwang-Jae Lim

Seung-Ku Hwang

Myeong-Cheol Shin

Byung-Jae Kwak

Chung-Gu Kang

Xiqi Gao

Xiaohu You

Seong-Keun Oh

Seung-Jun Lee

Wenjin Wang

Ji-Won Kang

Youn-Ok Park

Jee-Hwan Ahn

Chungyong Lee

Dong-Cheol Kim

Sook-Jin Lee

Sung-Cheol Chang

Een-Kee Hong

Hyun-Joon Shin

Hyung-Ho Park

Nah-Oak Song

Yong-Seouk Choi

Hee-Goo Han

Jun-Ho Son

Moon-Il Lee

Jin-Ho Choi

Choong-II Yeh

Choomg-Il Yeh

Myoung-Seog Kim

Hyung-Soo Lim

Dong-Hyun Ahn

Hyong-Woo Ku

An intelligent multiple access communication (MAC) control apparatus and method are disclosed. The intelligent MAC control apparatus includes a connection control unit, a resource management unit, a session control unit, a flow control unit, and a determination unit. The connection control unit connects at least one Radio Access Technology (RAT) and a wireless network. The resource management unit collects RAT information including information about available resources and radio state of the RAT. The session control unit checks the QoS of at least one connection target service. The flow control unit determines the priority of the connection target service, and selects a preferential connection target service. The determination unit determines a connection RAT for performing the preferential connection target service based on the QoS and the RAT information.

Intelligent multiple access communication control apparatus and method

The present invention relates a symbol generation apparatus for multiple antennas having low receiving complexity and having flexibility with respect to an increase in the number of antennas. The symbol generation apparatus includes a plurality of space-time channel encoders respectively corresponding to a plurality of channels, and an inverse fast Fourier transformer group. The respective space-time channel encoders receive a digital-modulated symbol group from the corresponding channel, perform a space-time encoding operation with respect to a plurality of space areas and at least one time area, shift phases by using a plurality of phase values, and generate a plurality of phase-shifted space-time codewords. The inverse fast Fourier transformer group performs an inverse fast Fourier transform operation by using the plurality of phase-shifted space-time codewords in a plurality of subcarriers respectively corresponding to the plurality of channels, and generates a plurality of inverse fast Fourier transformed signals.

Apparatus and method for generating symbol for multiple antennas

A cell search system for a mobile station in a time division duplex system includes: a primary synchronization code search module for searching primary synchronization codes and comparing frame values of the primary synchronization codes to determine a position of the maximum value; a correlation module for estimating a phase value and acquiring a first correlation value; a secondary synchronization code search module for generating determinative variables and storing them based on the position of the maximum value; a comparison and decision module for detecting a maximum value of the determinative variables, comparing it with the values stored in the secondary synchronization code search module to count matching values, and comparing the count value with a system value to decide whether slot synchronization and group acquisition is successful; and a base station determination module for determining a second correlation value between midamble codes and the received signals, and selecting a maximum value of it to determine a base station.

Cell search system for mobile station in time division duplex system and method for the same

The present invention relates to a multiple antenna transmission system and a signal transmission method In the signal transmission method using multiple antennas, a plurality of subcarrier symbols are grouped as a plurality of groups including first and second tiles that are basic resource management units including two or more subcarriers included in a set frequency domain, phases of subcarrier symbols included in a first tile are shifted to be a first phase shifting value, and phases of subcarrier symbols included in a second tile are shifted to be a second phase shifting value that is different from the first phase shifting value.

Signal transmission system using multiple antenna and signal transmission method thereof

The present invention relates to an uplink control channel configuration in a mobile wideband wireless access system, and an allocation method thereof. An uplink control channel includes a long cyclic prefix used to improve interference and distortion caused by multipath transmission characteristics of an initial ranging or handover ranging signal and a periodic ranging or band request ranging signal. In addition, a short orthogonal frequency division multiple (OFDM) symbol is used to transmit uplink control information when one terminal exists or the number of terminals is small.

Structure and construction method of uplink control channel in mobile wideband wireless access system

The present invention relates to a method for allocating a frequency domain spread code in a base station of a multi-carrier code division multiple access (MC-CDMA) communication system. A code allocation priority is established based on interference between previously allocated spread codes and a newly allocated spread code so as to minimize the interference caused by channel fading or a synchronization error according to a transmitting or receiving timing offset when a scheduler of the base station in the MC-CDMA communication system allocates a subcarrier group to the plurality of user terminals or channels, and the spread code is allocated to the plurality of user terminals or channels according to the established priority, by the scheduler of the base station.

Method for allocating frequency domain spread code in base station of MC-CDMA communication system

The present invention relates to a method for timing acquisition and carrier frequency offset estimation of an OFDM communication system and an apparatus using the same. For this purpose the present invention provides a method for calculating at least one auto-correlation and calculating an observation value by performing a sliding sum on the at least one auto-correlation, and calculating a peak point of an absolute value of the observation as frame timing. In addition, the present invention provides a method for generating a third OFDM symbol that is generated by delaying a second OFDM symbol, calculating an observation value through the second and third OFDM symbols, and calculating a phase difference from a result of multiplication of the observation value and a conjugate complex value of the observation value such that a carrier frequency offset can be estimated. According to the present invention, the number of OFDM symbols is sufficient for obtaining timing acquisition with high reliability, and the offset estimation algorithm having a lower implementation complexity is provided such that superior performance is expected and carrier frequency offset with high reliability can be achieved.

System and method for timing acquisition and carrier frequency offset estimation in wireless communication based on OFDM

The present invention relates to a method of forming a random beam, and a beam forming apparatus. A quantization preprocessor and a random unitary matrix having a predetermined pattern are used to form a beam on a mobile terminal. A base station forms a beam using a codeword index of a quantization codebook received from a mobile terminal and channel quality information corresponding to the codeword index, and the mobile terminal generates the codeword index and the channel quality information using pilot signals generated by the base station. The number of pilot signals is equal to the number of transmitting antennas. Therefore, a codebook that has been known to both the mobile terminal and the base station is used, and the mobile terminal can select the codeword index for quantization, which makes it possible to selectively give diversity and thus improve the system efficiency.

Beam forming method and apparatus

When an event associated with a mobile station occurs, a relay station requests a base station to allocate a dedicated control channel required for transmitting control information on the mobile station to the base station. Next, when the control information on the mobile station is generated, the relay station transmits the control information to the base station through the dedicated control channel. Accordingly, since the base station allocates the dedicated control channel to the relay station in advance before the control information is generated in the relay station, the relay station can transmit the control information to the base station with a minimum of time delay.

Apparatus and method for relaying between base station and mobile station, and method for receiving control information

The present invention relates to a precoder and a precoding method in a multi-user multi-antenna communication System. When a transmission part () having a plurality of antennas transmits a plurality of signals to a receiving part () having an antenna, the precoder and the precoding method using the same prevents System performance degradation caused by interference signals and efficiently reduces transmission power while changing the constellation rotary angle. When the power is controlled by using the precoder, the System performance is enhanced while not damaging the structural gain of the existing multi-user multi-antenna precoder.

Precoding device and method in wireless communication system

Disclosed is a binary signal modulator for minimizing deterioration of receiving performance caused by phase error. The binary signal modulator receives binary signals, and converts the binary signals into complex symbols according to a predetermined mapping relation. Here, the mapping relation is generated when a plurality of mapping symbols are arranged on a plurality of trajectories so that the distance between the mapping symbols is greater than or equal to a predetermined distance and the phase between the mapping symbols is greater than or equal to a predetermined angle from among the trajectories starting from a plurality of points on the complex plane, and a distance between the trajectories is greater than or equal to the minimum distance from among the distances between the points.

Method for deciding position of mapping symbols, and device and method for modulating binary signal

A space domain filter detecting method in a multi-antennas wireless communication system, which processes time and space domain interference differently. The space domain filter detecting method comprises the following steps: firstly, the received signals are matched-combined in time domain and space domain; secondly, using the combined signals as an observation value, the space domain filtering is performed; thirdly, an estimated value is subtracted from the filtered signals, and the result is taken as a detection output, which is sent to a determiner in a non-error control coding system to get a hard determination output or is sent to a determiner in an error control coding system to get a soft determination output that is finally sent to a coder. The method promotes the transmission rate and the anti-interference ability and advances the spectrum efficiency.

Space domain filter detecting method in a multi-antenna wireless communication system

The present invention relates to a multi-input multi-output (MIMO) system for enhancing transmission performance. The MIMO system uses space-time encoding and transmit antenna selection methods, and includes a transmitter () and a receiver (). The transmitter () includes N transmit antennas (--) that are more than M transmit antennas (--) used for transmitting a signal to space channel, selects the M transmit antennas (--) among the N transmit antennas (--), and transmits symbol by space-time encoding the symbol. The receiver () includes M receive antenna (--) for receiving a signal from the space channel, detects an information symbol by using the signal received through the receive antenna (--), generates transmit antenna selection information for selecting M transmit antennas (--) among transmit antennas (i--) with reference to a channel estimate, and returns the information to the transmitter.

Multi-input multi-output system for enhancing transmission performance

Respective codewords of quantization codebooks corresponding to a number of data streams are selected based on channel information estimated by a received training symbol. A stream mode is selected among stream modes to determine a modulation method applied to each data stream. The data stream is detected by using the codeword corresponding to the quantization codebook of the data stream corresponding to the selected stream mode as a precode matrix, and the detected data stream is modulated. In this case, a receiving apparatus performs a feedback operation so that indexes of the selected stream mode and the codeword used as the precode matrix may be transmitted to the transmitting apparatus. The transmitting apparatus selects the number of transmitted data streams and the modulation method based on the transmitted index of feedback streams by the feedback operation.

Transmitting apparatus and method, and receiving apparatus and method in multple antenna system

A sphere decoder sets a Euclidean distance between a lattice vector obtained by using an MMSE or ZF estimate and a received signal as an initial radius, further reduces the initial radius, and searches lattices points included inside a hypersphere with the further reduced initial radius. In addition, one lattice vector having a minimum Euclidean distance is output. One dimension is selected to reduce an initial radius, and estimates in other dimensions are kept fixed, excluding the selected dimension. Then candidate lattice points are searched in the selected dimension, excluding a current estimate, such that a minimum Euclidean distance and a lattice point estimate corresponding to the minimum Euclidean distance are obtained. The initial radius is updated by the minimum Euclidean distance, and a final lattice vector is constructed by combining a lattice point estimate corresponding to the initial radius and the lattice point estimates in other dimensions.

Sphere decoder and decoding method thereof

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Daejeon, South Korea

Dong-Seung Kwon