Abstract: A method of transmitting and receiving a control channel in a wireless communication system is provided. A base station allocates a data channel to a radio resource, adds start position information of the data channel into a payload of a control channel, and performs signaling for indication information on the start position information added into the payload of the control channel to a terminal. Accordingly, the legacy system and the enhanced system can efficiently transmit a control channel.

Abstract: Disclosed is a communication system which transmits Acknowledgement (ACK)/Negative Acknowledgement (NACK) information on downlink data by using an uplink control channel. The communication system individually allocates radio resources for a plurality of slots included in an uplink subframe. Consequently, uplink radio resources may be used freely, and it is even possible to flexibly handle a situation in which the amount of the ACK/NACK information is increased.

Abstract: Provided is a data transmission system using a carrier aggregation. The data transmission system may assign a radio resource based on a correspondence relationship between a downlink and an uplink, and may transmit data using the assigned radio resource.

Abstract: A method for generating a downlink signal and searching for a cell from the downlink signal in an OFDM-based cellular system is provided. Thus, a pilot pattern is formed in the downlink signal, and the pilot pattern is formed of a product of a cell-specific scrambling code and a cell group-specific code. The scrambling code is different for each cell and the same for each sub-frame, and the cell group-specific code is different for each cell and different for each sub-frame.

Abstract: Provided are a detecting apparatus in a Multiple Input Multiple Output (MIMO) system and a method thereof. The apparatus includes a first detector for decoding a received signal, to thereby generate a decoded vector; a candidate elements decision unit for calculating an instantaneous signal-to-interference plus noise ratio (SINR) value for each element of the decoded vector, and deciding candidate elements for estimating a transmission data based on the decoded vector by comparing the calculated instantaneous SINR value and a threshold value; a signal eliminator for generating a signal with respect to the candidate elements determined in the candidate elements decision unit and outputting a modified signal by subtracting the signal from the received signal; and a second detector for decoding the modified signal received from the signal eliminator based on a more precise detection method than the first detector.

Abstract: Provided is a method for retransmitting packet in a Multiple Input Multiple Output (MIMO) system. The method includes: in a receiving block, decoding packets received from a transmitting block and detecting whether an error exists or not in the packets; if the error is detected, transmitting a negative acknowledgement (NACK) signal informing transmission failure of the packets to the transmitting block; calculating channel quality information (CQI) values for transmission-failed packets after performing successive interference cancellation (SIC) with respect to all antenna combinations to retransmit the transmission-failed packets; and selecting an antenna combination having CQI values of the transmission-failed packets which are equal to or greater than respective initial CQI values of the transmission-failed packets among the antenna combinations, and transmitting information of the selected antenna combination to the transmitting block.

Abstract: The present invention relates a method and apparatus for transmitting/receiving data using multiple codewords in a communication system using SC-FDMA (single carrier frequency division multiple access). A transmitter generates the multiple codewords for user data and transmits the generated multiple codewords. A receiver receives the multiple codewords and sequentially performs decoding and SIC (successive interference cancellation) on the received multiple codewords. Therefore, this structure can minimize a PAPR (peak to average power ratio) and considerably reduces interference between symbols in a frequency selective fading environment.