Abstract:
A method for transmitting/receiving data in a Multiple Input Multiple Output (MIMO) communication system is disclosed. The data transmission method includes determining a precoding matrix to be a part of a phase-shift-based precoding matrix, determining a first diagonal matrix for phase shift to be a part of the phase-shift-based precoding matrix, determining a unitary matrix to be a part of the phase-shift-based precoding matrix, precoding a transmission symbol for each resource using the phase-shift-based precoding matrix to produce precoded data, and transmitting the precoded data, wherein the phase-shift-based precoding matrix is determined by the product of the precoding matrix, a Hermitian matrix of the unitary matrix, the first diagonal matrix, and the unitary matrix.
Abstract:
A pilot transmission method in a wireless communication system is provided. The method includes: transmitting a first pilot for channel measurement through a first transmission section; and transmitting a second pilot for channel measurement through a second transmission section which is subsequent in time to the first transmission section, wherein the first transmission section and the second transmission section include a plurality of sub-bands, parts of the plurality of sub-bands use predetermined precoding whereas the remaining sub-bands use non-predetermined precoding, and any one of the first pilot and the second pilot is carried only on a sub-band which uses the predetermined precoding whereas the other pilot is carried on the entirety of the plurality of sub-bands.
Abstract:
A method for setting uplink transmission power at a mobile station in a wireless communication system comprises the steps of: receiving information on the number of total streams received at a base station; and setting the uplink transmission power using the received number of total streams. In this case, the uplink transmission power is preferably a transmission power per stream (PTx—stream) obtained by applying the number of total streams to reference transmission power (PTx—ref).
Abstract:
The present invention relates to a segment identifier detection method performed by a terminal if a segment being administrated by a base station in a wireless communication system has the frequency reuse factor of 3 and 2 at the same time. In particular, the method comprises: acquiring a cell identifier and a segment identifier corresponding to the cell identifier from a secondary advanced preamble (SA-preamble) that has been received from the base station; determining a frequency reuse factor of the base station; and if the frequency reuse factor is 2 and the obtained segment identifier is a third segment identifier, transforming the segment identifier corresponding to the cell identifier into a first segment identifier or a second segment identifier.
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:
The present invention relates to a precoding matrix information transmission method and a user device, and provides a method for transmitting precoding matrix information by a particular user device among user devices that receive a signal transmitted from one base station. The method comprises the steps of: determining, from a predetermined codebook, a first precoding matrix which is a precoding matrix for the particular user device during signal reception, and determining one or more second precoding matrices for the other user devices which are to be multiplexed in a predetermined resource region with the particular user device, wherein the one or more second precoding matrices are determined within a codebook subset of the predetermined codebook linked with the first precoding matrix; and transmitting, to the base station, first precoding matrix information indicating the first precoding matrix and second precoding matrix information indicating the one or more second precoding matrices.
Abstract:
A user equipment (UE) receiving a plurality of reference signals in a wireless multiple-input multiple-output (MIMO) communication system includes a transceiver configured for receiving the plurality of reference signals for multiple antennas in a sub-frame, the sub-frame including a plurality of Orthogonal Frequency Division Multiplexing (OFDM) symbols in a time domain over a plurality of sub-carriers in a frequency domain. A first array is repeated in the frequency domain on a first OFDM symbol of the sub-frame, a second array is repeated in the frequency domain on a second OFDM symbol of the sub-frame and a third array is repeated in the frequency domain on a third OFDM symbol of the sub-frame, and each of the first, second and third arrays consists of six contiguous symbols in the frequency domain.
Abstract:
A method for a user equipment to precode and transmit an uplink signal efficiently in a 4-antenna system and a method for a base station to receive the transmitted signal efficiently are disclosed. Four antennas of a user equipment can be grouped by a 2-antenna unit. In consideration of this antenna group, it is able to perform precoding using antenna selection/DFT matrix of the antenna group unit. Moreover, a rank-3 codebook can be configured to include a precoding matrix of a type in consideration of power balance per antenna and a precoding matrix including one non-zero component only in one row for maintaining a good CM property.
Abstract:
The present invention relates to a wireless communication system. More particularly, the present invention relates to a method and apparatus which indicate, using multiple CQIs, channel quality in the event multiple users are scheduled in the same time/frequency area, and to a method and apparatus which estimate a channel state using said multiple CQIs. According to the embodiments of the present invention, a channel state can be estimated in a more accurate manner in a multi-user MIMO system.
Abstract:
A method of transmitting control signals includes configuring a multiplexing indicator indicating that a plurality of control signals are multiplexed on a control channel, generating a multiplexed control signal by multiplexing a first control signal and a second control signal according to the multiplexing indicator and transmitting the multiplexed control signal on the control channel. Overhead due to control signaling can be reduced by transmitting a multiplexed control signal on a control channel.