Abstract: Disclosed is a method for transmitting/receiving data by use of feedback information in a closed loop multi input multi output (MIMO) mobile communication system. The method includes the steps of feeding back transmission eigenvector selection information determined through a singular value decomposition (SVD) of a channel matrix and transmitting the transmission eigenvector selection information to a transmitter; and receiving the feedback transmission eigenvector selection information, selecting transmission data according to the received transmission eigenvector selection information, mapping the selected transmission data to at least one transmission antenna, and transmitting the transmission data to a receiver.

Abstract: An apparatus and method for receiving a signal in a signal reception apparatus of a communication system is provided. The signal reception method includes receiving a signal, and decoding the received signal using a Low Density Parity Check (LDPC) decoding scheme according to the number of quantization bits.

Abstract: An apparatus and method for transmitting and receiving a signal in a communication system are provided. The signal transmission apparatus generates a parity check matrix for an LDPC code in accordance with a code rate to be used and generates a codeword vector by encoding an information vector using the parity check matrix. When the code rate is a first code rate, the signal transmission apparatus generates a first parity check matrix as the parity check matrix for the LDPC code. When the code rate is the second code rate, the signal transmission apparatus generates a second parity check matrix supporting a second code rate lower than the first code rate by adding columns of a degree of 1 and columns of a degree of 2 to the first parity check matrix and generates the second parity check matrix as the parity check matrix for the LDPC code.

Abstract: A method for generating a non-binary Low Density Parity Check (LDPC) code. The method includes generating non-binary identity matrixes so as to satisfy at least one condition, wherein the non-binary LDPC code is defined by a parity check matrix, and the parity check matrix includes a plurality of sub-matrixes, which are divided into zero matrixes and the non-binary identity matrixes.

Abstract: Provided is an apparatus and method for estimating an uplink frequency offset in a wireless communication system. In a receiving apparatus of a wireless communication system using a random access channel composed of two equivalent sequences, the apparatus includes a channel receiver which extracts samples corresponding to the two sequences from an input random access channel signal; a correlator which computes first and second correlation values by correlating preceding and trailing samples among the samples output from the channel receiver with a predetermined sequence; and a frequency offset estimator which estimates a frequency offset by using a ratio of the second correlation value to the first correlation value output from the correlator.

Abstract: A method and system for allocating resources in a communication system including a first system having a use right for a plurality of frequency bands, and a second system having no use right for the plurality of frequency bands. The method includes acquiring first, second and third sensing informations indicating frequency bands available by a base station, a relay station and a mobile station belonging to the second system, among the plurality of frequency bands; and selecting a frequency band to be allocated for communications, based on the acquired sensing informations.

Abstract: An apparatus and a method for transmitting broadcasting signals in a broadcasting system having multi-antenna are provided. The apparatus comprises at least one antenna, a signal generator for generating two or more broadcasting signals to be transmitted, at least two of the two or more broadcasting signals being generated according to different user-required quality characteristics, a multi-antenna modulator for modulating each of the broadcasting signals according to one of a plurality of multi-antenna transmission methods selected for each of the broadcasting signals according to the user-required quality characteristics of the respective broadcasting signals, and a transmitter for transmitting the modulated signals via the at least one antenna.

Abstract: A method and system for transmitting/receiving data in a heterogeneous communication system. A terminal accesses a first controller of a first communication system supporting a first communication service to make a communication path to the first communication system. After making the communication path to the terminal, the first controller determines whether it is possible to provide the first communication service to the terminal over the first communication system. If it is not possible, the first controller transmits to an interworking unit a first request indicating that the terminal requires the first communication service over the second communication system. The interworking unit transmits a second request to a second controller of the second communication system in response to the first request, the second request indicating that the second controller provides the first communication service to the terminal.

Abstract: A method and apparatus for generating a hopping sequence according to a seed value in a communication system are provided. The apparatus and method for generating a hopping sequence indicating a hopping pattern of carrier frequencies or time slots in a communication system include, when a seed value is input, setting a window to be applied to the seed value, calculating a window value according to the set window and generating a sequence by storing values in sequence arrangement to the calculated window value. The apparatus and method reduce the necessary size of a memory unit for storing a hopping sequence.

Abstract: An apparatus and method for supporting both a receiver using a single antenna and a receiver using multiple antennas in a Multiple Input Multiple Output (MIMO) wireless communication system are provided. The apparatus and method in a MIMO wireless communication system include a first synthesizer for generating a first Transmit (Tx) signal by adding a first signal and a second signal, a second synthesizer for generating a second Tx signal by subtracting the second signal from the first signal and a plurality of transmitting units for transmitting the first Tx signal and the second Tx signal through corresponding antennas. Accordingly, receivers having either a single antenna or multiple antennas may be employed in the same communication system.

Abstract: A method and apparatus for providing a voice message in a communication system are provided. Upon receiving a request message for providing a voice message to a calling terminal, a caller information detector determines whether the request message includes language select information indicating a language of a voice message to be provided to the calling terminal, and detects caller information included in the request message when the language select information is not included. A voice message reproducer selects a language of a voice message to be provided to the calling terminal using the detected caller information, and transmits a voice message corresponding to the selected language to the calling terminal. Accordingly, the calling terminal can receive voice messages in a language appropriate for the user.

Abstract: A signal reception method and apparatus for a communication system. One input unit and dc?1 delay nodes each receive one input message. A comparison unit compares magnitudes of the input messages being input to the dc?1 delay nodes, and outputs an input message having a minimum magnitude as an output message. After the comparison unit outputs the output message, a controller cyclic-shifts the input messages being input to the one input unit and the dc?1 delay nodes according to a control signal.

Abstract: A method and system for configuring a frame in a communication system is provided.

Abstract: Disclosed is a method for transmitting data bursts by a base station in a communication system, including forming one group which includes at least one subchannel and transmitting at least two data bursts having an equal transmission characteristic through each subchannel included in the group.

Abstract: An apparatus and a method for selecting one of a plurality of relay modes in a wireless communication system are provided. The method includes checking a channel state between a Mobile Station (MS) and each of at least one Relay Station (RS), selecting the relay mode for supporting a relay service using the determined channel state between the MA and each of the at least one RS, and providing the relay service to the MS using the selected relay mode. Thus, system throughput and outage performance can be enhanced by using the appropriate relay mode based on the MS distribution or the channel condition.

Abstract: A transmitter for a mobile communication system based on an OFDM scheme and a method for controlling the same. The transmitter can implement a characteristic of a multiple access scheme based on an OFDM scheme, a characteristic of a CDMA scheme, and a characteristic of a frequency hopping scheme which has very strong resistance to the frequency selective fading.

Abstract: A method to transmit a packet of a BS in a communication system using a HARQ scheme is provided. The method includes assigning resource for transmitting a packet to a mobile station, and transmitting a first packet to the mobile station using the assigned resource; transmitting timing information on which a second packet is transmitted to the mobile station when the BS does not receive information indicating that the mobile station decoded the first packet successfully or when the BS receives information indicating that the mobile station failed to decode the first packet; and transmitting the second packet to the mobile station on a timing point corresponding to the timing information.

Abstract: A transceiver system and method in an OFDM communication system which enables exact symbol synchronization acquisition and improves performance for frequency offset and channel estimation. In the apparatus, a guard interval filling unit copies data at a predetermined interval in an input data row inputted to be transmitted, and fills in the copied data in the preset guard interval in the input data row. A selection unit selectively receives an output data row outputted from the guard interval filling means and unique words having a constant amplitude and a non-periodic auto-correlation characteristic, and outputs the OFDM symbol in which the unique words are inserted in the output data row.

Abstract: An apparatus for transmitting/receiving a signal in a communication system is provided. A Mobile Station (MS) spreads a transmission signal to generate a spreading signal, receives, from a Base Station (BS), information on a second spreading signal transmission region, extended from a first spreading signal transmission region, and maps the generated spreading signal to a subcarrier in the second spreading signal transmission region. A Base Station (BS) transmits information on a second spreading signal transmission region extended from a first spreading signal transmission region, for reception of a spreading signal, receives a spreading signal mapped to subcarriers over the second spreading signal transmission region, from an Mobile Station (MS), detects a spreading signal from the spread signal mapped to the subcarriers, and despreads the detected spreading signal to restore a transmission signal.

Abstract: Provided are an apparatus and method for receiving a signal in a communication system, in which a signal is received and decoded by setting an offset indicating a start position of a node operation for each block column of a parity check matrix of a Low Density Parity Check (LDPC) code and scheduling an order of performing the node operation on a Partial Parallel Scheduling (PPS) group basis. Here, the parity check matrix includes p×L rows and q×L columns, the p×L rows are grouped into p block rows, the q×L columns are grouped into q block columns, and each PPS group includes one column from each of the q block columns.