Abstract: A method for transmitting a reference signal in a multi-antenna system is provided. The method includes: selecting at least one orthogonal frequency division multiplexing (OFDM) symbol in a subframe containing a plurality of OFDM symbols; allocating a channel quality indication reference signal (CQI RS) capable of measuring a channel state for each of a plurality of antennas to the selected at least one OFDM symbol; and transmitting the CQI RS, wherein the CQI RS is allocated to an OFDM symbol which does not overlap with an OFDM symbol to which a common reference signal to be transmitted to all user equipments in a cell or a dedicated reference signal to be transmitted to a specific user equipment in the cell is allocated.

Abstract: A method for transmitting a demodulation reference signal (DMRS) for a physical uplink shared channel (PUSCH), by a user equipment (UE), in a wireless communication system. The UE generates first, second, and third DMRS sequences, which are associated with first, second, and third layers respectively, by applying first, second, and third cyclic shifts to the first, second, and third DMRS sequences respectively. The UE transmits the first, second, and third DMRS sequences to a base station, wherein the first, second, and third cyclic shifts are determined based on first, second, and third cyclic shift values respectively. The first and second cyclic shift values are separated from each other by a maximum separation value, which is determined based on a total number of cyclic shifts. The third cyclic shift value is determined by increasing cyclically by a median separation value between the first and second cyclic shift values.

Abstract: A method for mapping, by a base station, a channel state information reference signal (CSI RS) in a wireless communication system, the method comprising: generating the CSI for eight antenna ports; selecting a resource element (RE) set from a plurality of RE sets in a subframe using an extended cyclic prefix (CP), wherein the selected RE set includes four pairs of REs in consecutive orthogonal frequency division multiplexing (OFDM) symbols, and wherein the four pairs of REs are separated from each other by constant subcarrier spacing in the consecutive OFDM symbols; and mapping the CSI RS for the eight antenna ports to the selected RE set.

Abstract: A method for transmitting a demodulation reference signal (DM-RS), by a user equipment (UE), in a wireless communication system is discussed. The method includes receiving, by the UE from a base station, a cyclic shift field in downlink control information (DCI), wherein the cyclic shift field indicates first, second, and third cyclic shift values for first, second, and third layers respectively, generating, by the UE, first, second, and third DMRSs for the first, second, and third layers respectively, based on first, second, and third cyclic shifts respectively, wherein the first, second, and third cyclic shifts are determined based on the first, second, and third cyclic shift values respectively, and transmitting, by the UE to the base station, the first, second, and third DMRSs.

Abstract: A method for transmitting control information via a PUCCH in a wireless communication system and an apparatus for performing the method are provided, the method including joint-coding a plurality of pieces of control information to obtain a single code word; obtaining a first modulated symbol sequence from the single code word; obtaining a plurality of second modulated symbol sequences corresponding to each slot in the PUCCH from the first modulated symbol sequence; cyclically shifting the plurality of second modulated symbol sequences in a time domain to obtain a plurality of third modulated symbol sequences; performing a Discrete Fourier Transform (DFT) precoding process on the plurality of third modulated symbol sequences to obtain a plurality of complex symbol sequences in a frequency domain; and transmitting the plurality of complex symbol sequences via the PUCCH.

Abstract: A technique for receiving and transmitting downlink reference signals is disclosed. When transmitting downlink data demodulation reference signals (DMRS) (or reference signals for downlink data demodulation) by using two or more layers, the DMRS of each layer may be multiplexed by using a code division multiplexing method and then transmitted. The DMRS for each of the two or more layers may be used for one user equipment or for two or more user equipments. And, downlink control signals for transmitting and receiving such DMRS may be configured to have the same format regardless of a single-user mode (or SU-MIMO mode) or a multi-user mode (or MU-MIMO mode), thereby being used.

Abstract: A method is provided for demodulating a signal. A relay node receives control information, from an evolved-NodeB (eNB), through a relay-physical downlink control channel (R-PDCCH), and receives a data, from the eNB, through a physical downlink shared channel (PDSCH). When a number of transmission layers of the PDSCH is 2 or more than 2 and a plurality of reference signals for a demodulation of the data are transmitted on antenna ports by the eNB, a reference signal transmitted on a minimum antenna port among the antenna ports is used for a demodulation of the control information.

Abstract: A user equipment in wireless communication system is provided. The user equipment includes an antenna unit including a plurality of antennas, a control unit for grouping the plurality of antennas into a predetermined number of antenna groups and controlling separately transmission power of each of the predetermined number of antenna groups, and a transmitting unit, connected to the control unit, for transmitting at least one of data and control information to a base station via at least one of the predetermined number of antenna groups.

Abstract: A method and apparatus for requesting uplink resources in a wireless communication system is provided. A user equipment determines whether a scheduling request for requesting uplink resources is triggered. If the scheduling request is triggered, the user equipment transmits a first set of frequency domain sequences and a second set of frequency domain sequences in a subframe.

Abstract: The present invention relates to a wireless communication system and provides an efficient control information transmission method and apparatus for supporting a multiple antenna transmission technique. A method is provided for transmitting downlink hybrid automatic repeat request (HARQ) information related to an uplink multiple codeword transmission and includes receiving the uplink multiple codeword transmission, generating HARQ information related to each of the multiple codewords based on a result of decoding each of the multiple codewords, modulating the HARQ information, and transmitting the modulated HARQ information via one or more physical HARQ indicator channels (PHICHs).

Abstract: A method for transmitting an aperiodic sounding reference signal (SRS) to a base station by a user equipment (UE) in a wireless communication system, the method includes receiving, from the base station, an uplink grant or a downlink grant, with an indicator indicating a transmission of the aperiodic SRS; and transmitting, to the base station, the aperiodic SRS in a first uplink subframe; wherein the first uplink subframe is a subframe firstly configured after a second uplink subframe for the aperiodic SRS, wherein, if the uplink grant is received, the second uplink subframe is a subframe in which an uplink data signal scheduled by the uplink grant is transmitted, wherein, if the downlink grant is received, the second uplink subframe is a subframe in which an uplink control signal corresponding to the downlink grant is transmitted.

Abstract: A method for transmitting, by a user equipment (UE), an aperiodic sounding reference signal (SRS) in a wireless communication system, the method including receiving, via a physical downlink control channel (PDCCH), downlink control information (DCI) for downlink scheduling. The DCI includes an SRS request for triggering transmission of the aperiodic SRS. The method further includes detecting the SRS request; and transmitting the aperiodic SRS on an uplink (UL) component carrier (CC), which is linked to a downlink (DL) CC in which a physical downlink shared channel (PDSCH) is scheduled by the DCI, among a plurality of UL CCs. If a carrier indicator field (CIF) is configured, the UL CC is indicated by the CIF.

Abstract: A base station does not transmit any reference signal (RS) for channel measurement in a subframe in which transmission of an RS collides with transmission of a synchronization signal or a broadcast signal or in a resource block including the synchronization signal or the broadcast signal in the subframe. A user equipment assumes that any RS for channel measurement is not transmitted in a subframe or in a resource block when transmission of an RS collides with transmission of a synchronization signal or a broadcast signal in the subframe or in the resource block.

Abstract: Disclosed are a method and a device for transmitting uplink control information (UCI) by a terminal in a wireless communication system. The UCI transmission method comprises the steps of: generating an encoding information bit stream by performing channel coding for a UCI bit stream; generating complex modulation symbols by performing modulation for the generated encoding information bit stream; spreading the complex modulation symbols in block-wise on the basis of an orthogonal sequence; and transmitting the spread complex modulation symbols to a base station. The encoding information bit stream is generated by a channel coding for circularly repeating the UCI bit stream.

Abstract: A method for monitoring a control channel in a multiple carrier system, and a user equipment (UE) therefore are discussed. The method according to one embodiment includes, if an aggregation of carriers is configured and if a carrier indicator field (CIF) is configured, monitoring a plurality of downlink control channels within a plurality of UE-specific search spaces of a first carrier; and receiving downlink control information (DCI) on at least one of the plurality of the downlink control channels, which is successfully decoded, via the first carrier. The DCI includes scheduling information on either a downlink channel or an uplink channel in a second carrier.

Abstract: A method and apparatus for multiplexing reference signals in a predetermined number of Code Division Multiplexing (CDM) groups to balance power across Orthogonal Frequency Division Multiplexing (OFDM) symbols are disclosed. In a wireless communication system, orthogonal sequences used for spreading the reference signals are allocated such that the order of orthogonal sequences allocated to a subcarrier of one CDM group has a predetermined offset with respect to the order of orthogonal sequences allocated to a subcarrier of another CDM group, adjacent to the subcarrier of the one CDM group.

Abstract: A method for transmitting control information via a PUCCH in a wireless communication system and an apparatus for performing the method are provided, the method including joint-coding a plurality of pieces of control information to obtain a single code word; obtaining a first modulated symbol sequence from the single code word; obtaining a plurality of second modulated symbol sequences corresponding to each slot in the PUCCH from the first modulated symbol sequence; cyclically shifting the plurality of second modulated symbol sequences in a time domain to obtain a plurality of third modulated symbol sequences; performing a Discrete Fourier Transform (DFT) precoding process on the plurality of third modulated symbol sequences to obtain a plurality of complex symbol sequences in a frequency domain; and transmitting the plurality of complex symbol sequences via the PUCCH.

Abstract: According to one embodiment, a method for transmitting, by a user equipment (UE), information in a wireless communication system includes: determining a first information sequence based on a first cyclically shifted base sequence and a first orthogonal sequence by using a first physical uplink control channel (PUCCH) resource for a first antenna, wherein the first PUCCH resource is obtained based on a channel control element (CCE) index related to a physical downlink control channel (PDCCH) and a parameter configured by a higher layer; determining a second information sequence based on a second cyclically shifted base sequence and a second orthogonal sequence by using a second PUCCH resource for a second antenna, wherein the second PUCCH resource is obtained by adding an offset to the first PUCCH resource; transmitting the first information sequence via the first antenna; and transmitting the second information sequence via the second antenna.

Abstract: A method is provided for transmitting, by a user equipment (UE), a demodulation reference signal (DMRS) in a wireless communication system. A first DMRS sequence, which is associated with a first layer, and a second DMRS sequence, which is associated with a second layer, are transmitted to a base station. A first orthogonal cover code (OCC) is applied to the first and second DMRS sequences. A third DMRS sequence, which is associated with a third layer, and a fourth DMRS sequence, which is associated with a fourth layer, are transmitted to the base station. A second OCC is applied to the third and fourth DMRS sequences.

Abstract: A method for transmitting a sounding reference signal (SRS) at a user equipment in a time division duplex (TDD) communication system; and the user equipment are discussed. The method includes receiving downlink control information (DCI) including a request of the SRS transmission. The DCI includes information for receiving downlink data using multiple antennas by the user equipment. The method further includes transmitting the SRS to the base station according to the request of the SRS transmission.