Abstract: The present description relates to a method for performing client cooperation transmission through a group resource allocation (GRA) scheme in a wireless access system, comprising the following steps: receiving a group configuration message, including client group information, from a base station, wherein said group configuration message further includes client cooperation-enabled information that indicates whether or not the client group is concerned with the client cooperation transmission; determining whether or not to participate in the client cooperation by means of the client cooperation-enabled information; and transmitting the result of the determination on whether or not to participate in the client cooperation to the base station.

Abstract: A method of transmitting data in a multiple antenna system, including: transmitting a channel estimation signal including a first pilot for channel estimation of a first UE supporting multiple antennas and a second pilot for channel estimation of a second UE supporting a larger number of multiple antennas than that of the first UE; and receiving feedback data in response to the channel estimation signal.

Abstract: A method of transmitting a signal using a prescribed frame structure in a wireless communication system is disclosed. A mobile station is able to transmit or receive a signal using a frame structure with a CP length corresponding to ¼ of a useful symbol. Moreover, the mobile station is able to transmit or receive a signal using a frame structure with a CP length corresponding to ¼ of a useful symbol, which is designed to mutually coexist without causing collision or interference with another frame structure with a different CP length. In this case, a channel bandwidth of the prescribed frame structure is 7 MHz.

Abstract: A method of transmitting an uplink (UL) control signal of a relay station is provided. The method includes: configuring a UL relay zone for transmitting a signal by the relay station to a base station in a frame; configuring a resource unit including a plurality of symbols and a plurality of subcarriers to allocate the UL control signal in a subframe of the UL relay zone; and transmitting the UL control signal by using the resource unit, wherein, if a transition gap required for switching of signal transmission and reception of the relay station is included in the subframe, the UL control signal is transmitted in the remaining symbols other than the plurality of symbols constituting the resource unit including the transition gap.

Abstract: A method of transmitting and receiving feedback information in a multi-cell based wireless communication system using FFR, a mobile station apparatus therefore and a base station apparatus therefore are disclosed. A mobile station is able to obtain FFR configuration information including configuration information on at least one frequency partition to which a corresponding FFR is applied per cell ID. And, the mobile station is able to transmit PMI information to a serving base station using the obtained FFR configuration information. In this case, the PMI information is specifically restricted or recommended by the mobile station among PMIs (precoding matrix indexes) used by at least one neighbor cell in an allocated specific frequency partition.

Abstract: A method for reducing inter-cell interference and a method for transmitting a signal by a collaborative MIMO scheme, in a communication system having a multi-cell environment are disclosed. An example of a method for transmitting, by a mobile station, precoding information in a collaborative MIMO communication system includes determining a precoding matrix set including precoding matrices of one more base stations including a serving base station, based on signal strength of the serving base station, and transmitting information about the precoding matrix set to the serving base station. A mobile station in an edge of a cell performs a collaborative MIMO mode or inter-cell interference mitigation mode using the information about the precoding matrix set collaboratively with neighboring base stations.

Abstract: A method of transmitting an acknowledgment (ACK)/non-acknowledgement (NACK) signal in a wireless communication system includes assigning at least one ACK channel among a plurality of ACK channels which share an ACK channel region for transmitting the ACK/NACK signal, and transmitting the ACK/NACK signal through the at least one ACK channel, wherein the ACK channel region includes at least one tile including a plurality of data subcarriers, and the ACK/NACK signal of each ACK channel is indicated by mapping different orthogonal vectors respectively to the plurality of ACK channels in the tile.

Abstract: A method of data transmission from a transmitter of a wireless communication system which uses multiple antennas comprises receiving identification information of a precoding matrix from a receiver, the precoding matrix being selected from a codebook generated using a plurality of first matrices generated by multiplying a discrete fourier transform (DFT) matrix by each of a plurality of phase shift matrices; precoding data to be transmitted, by using a precoding matrix indicated by the identification information; and transmitting the precoded data to the receiver by using the multiple antennas.

Abstract: The present invention provides an embodiment of a method and system for applying a hybrid automatic repeat request (HARQ) scheme to a system employing a relay station. According to one embodiment of the present invention, a frame including an access zone and a relay zone can be configured based on the HARQ timing which can be calculated based on the structure of the access zone and relay zone. Also, according to one embodiment of the present invention, the structure of the access zone and relay zone can be determined by multiplexing communication systems that support two kinds of systems different from each other. According to one embodiment of the present invention, the HARQ scheme can be applied even to a frame including an access zone and a relay zone, by calculating the HARQ timing.

Abstract: A method for transmitting and receiving a precoded signal in a Multi-Input Multi-Output (MIMO) communication system is provided. In the method, a preceding matrix is selected from a codebook including one or more preceding matrices of each rank, each of the preceding matrices including a unitary matrix modified by an antenna selection element. A signal for transmission is then precoded by applying the selected preceding matrix to the signal for transmission and the precoded signal is transmitted through a selected antenna.

Abstract: The mobile station for transceiving signals using a predetermined time division duplex (TDD) frame structure in a wireless communication system includes a receiver for receiving a midamble from a base station (BS), and a relay station (RS). The receiver receives, from the BS, a first midamble through a second subframe of a downlink access zone of the BS and/or through a first subframe of a downlink relay zone that follows the downlink access zone. Alternatively, the receiver receives, from the RS, a second midamble through a second subframe of a downlink access zone of the RS. A transition gap in a downlink region is located in the last subframe of the downlink access zone of the RS, which follows the downlink access zone of the RS, and a transition gap in an uplink region is located in a first subframe of an uplink relay zone of the RS.

Abstract: A terminal unit for receiving a hybrid automatic retransmission request (HARQ) feedback using a frequency division duplex (FDD) frame comprises: a receiver, which receives an uplink assignment information element (A-MAP IE) for allocating each uplink through each downlink subframe of a first frame from a base station; a processor, which performs a process for transmitting uplink data that corresponds to the received A-MAP IE for allocating each uplink for a predetermined processing time: a transmitter, which transmits the processed uplink data to the base station from the respective downlink subframes having received the A-MAP IE for allocating each uplink, through each corresponding uplink subframe, after the predetermined processing time has lapsed; and a receiver, which receives, from the base station, the downlink HARQ feedback for each uplink data through each uplink subframe that has, in a third frame, the same index as the index of each downlink subframe where the A-MAP IE for allocating each uplink ha

Abstract: Provided are a method and an apparatus for transmitting a frame in a wireless communication system including a relay station. A base station sets a frame including a downlink (DL) access zone for transmitting a signal to the relay station and a DL relay zone for transmitting the signal to the relay station or a terminal, and transmits the frame. The DL access zone comprises a multiple-input multiple-output (MIMO) midamble for the terminal and the DL relay zone comprises an R-amble as an additional MIMO midamble.

Abstract: A method for reducing inter-cell interference and a method for transmitting a signal by a collaborative MIMO scheme, in a communication system having a multi-cell environment are disclosed. An example of a method for transmitting, by a mobile station, precoding information in a collaborative MIMO communication system includes determining a precoding matrix set including precoding matrices of one more base stations including a serving base station, based on signal strength of the serving base station, and transmitting information about the precoding matrix set to the serving base station. A mobile station in an edge of a cell performs a collaborative MIMO mode or inter-cell interference mitigation mode using the information about the precoding matrix set collaboratively with neighboring base stations.

Abstract: Disclosed are an apparatus and a method for performing communication using a half-frequency division duplex (H-FDD) frame structure in a mobile communication system. A user equipment for performing communication using an H-FDD frame structure according to the present invention comprises an RF unit in which each user equipment group receives and transmits signals using the H-FDD frame structure wherein the order of the downlink zone and uplink zone are reversely allocated to each of the groups. The downlink zone and uplink zone, which are allocated to each of the user equipment groups in the H-FDD frame structure, include a sub-frame wherein one or more symbols are allocated to idle time slots or are punctured. Each of the user equipment groups can receive and transmit signals using symbols that are not allocated to the idle time slots or are not punctured in the sub-frame.

Abstract: A method for retransmitting data in wireless communication system is disclosed. MS can receive a NACK (Not-Acknowledge) signal from a base station (BS) through a specific downlink subframe of a specific frame in a first superframe, and the MS can retransmits the data using a second uplink subframe in a first frame in a second superframe subsequent to a first superframe. In this case, a index of the second uplink subframe may be 1. The wireless communication system can support the Half-Frequency Division Duplex (H-FDD) scheme. A first uplink subframe in the first frame of the second superframe can be punctured.

Abstract: A method for reducing inter-cell interference and a method for transmitting a signal by a collaborative MIMO scheme, in a communication system having a multi-cell environment are disclosed. An example of a method for transmitting, by a mobile station, precoding information in a collaborative MIMO communication system includes determining a precoding matrix set including precoding matrices of one more base stations including a serving base station, based on signal strength of the serving base station, and transmitting information about the precoding matrix set to the serving base station. A mobile station in an edge of a cell performs a collaborative MIMO mode or inter-cell interference mitigation mode using the information about the precoding matrix set collaboratively with neighboring base stations.

Abstract: A method for reducing inter-cell interference and a method for transmitting a signal by a collaborative MIMO scheme, in a communication system having a multi-cell environment are disclosed. An example of a method for transmitting, by a mobile station, precoding information in a collaborative MIMO communication system includes determining a precoding matrix set including precoding matrices of one more base stations including a serving base station, based on signal strength of the serving base station, and transmitting information about the precoding matrix set to the serving base station. A mobile station in an edge of a cell performs a collaborative MIMO mode or inter-cell interference mitigation mode using the information about the precoding matrix set collaboratively with neighboring base stations.

Abstract: A method for reducing inter-cell interference and a method for transmitting a signal by a collaborative MIMO scheme, in a communication system having a multi-cell environment are disclosed. An example of a method for transmitting, by a mobile station, precoding information in a collaborative MIMO communication system includes determining a precoding matrix set including precoding matrices of one more base stations including a serving base station, based on signal strength of the serving base station, and transmitting information about the precoding matrix set to the serving base station. A mobile station in an edge of a cell performs a collaborative MIMO mode or inter-cell interference mitigation mode using the information about the precoding matrix set collaboratively with neighboring base stations.

Abstract: Disclosed is a method for conducting communication using a frame structure which supports two or more wireless communication schemes, and an apparatus using the method. A method for constructing an FDD frame according to the present invention efficiently supports a legacy system and an enhanced system using an H-FDD frame structure. Further, the method for constructing an FDD frame according to the present invention efficiently supports a terminal and an H-FDD terminal, which use different communication systems.