Abstract: A base station configured for outer loop power control receives an uplink dedicated channel transmission from a wireless transmit/receive unit. The base station transmits transmit power control commands in response to the received uplink channel transmission and determines if the wireless transmit/receive unit is in a discontinuous transmission mode. The base station adjusts a target SIR based on which transmission mode for the wireless transmit/receive unit is detected. The value for the transmit power control command is derived from the adjusted target SIR.

Abstract: The present invention is related to a method and apparatus for implementing space frequency block coding (SFBC) in an orthogonal frequency division multiplexing (OFDM) wireless communication system. The present invention is applicable to both a closed loop mode and an open loop mode. In the closed loop mode, power loading and eigen-beamforming are performed based on channel state information (CSI). A channel coded data stream is multiplexed into two or more data streams. Power loading is performed based on the CSI on each of the multiplexed data streams. SFBC encoding is performed on the data streams for each of the paired subcarriers. Then, eigen-beamforming is performed based on the CSI to distribute eigenbeams to multiple transmit antennas. The power loading may be performed on two or more SFBC encoding blocks or on each eigenmodes. Additionally, the power loading may be performed across subcarriers or subcarrier groups for weak eigenmodes.

Abstract: A method is disclosed for tuning a beamformed signal in wireless communications including a plurality of sub-carriers and a plurality of eigenbeams. The method includes adjusting a total gain of each of the plurality of sub-carriers and eigenbeams, and applying the adjusted total gain to each of the sub-carriers and each of the eigenbeams.

Abstract: A method and apparatus for decomposing a channel matrix in a wireless communication system are disclosed. A channel matrix H is generated for channels between transmit antennas and receive antennas. A Hermitian matrix A=HHH or A=HHH is created. A Jacobi process is cyclically performed on the matrix A to obtain Q and DA matrixes such that A=QDAQH. DA is a diagonal matrix obtained by singular value decomposition (SVD) on the A matrix. In each Jacobi transformation, real part diagonalization is performed to annihilate real parts of off-diagonal elements of the matrix and imaginary part diagonalization is performed to annihilate imaginary parts of off-diagonal elements of the matrix after the real part diagonalization. U, V and DH matrixes of H matrix are then calculated from the Q and DA matrices. DH is a diagonal matrix comprising singular values of the H matrix.

Abstract: A method and apparatus for implementing spatial processing with unequal modulation and coding schemes (MCSs) or stream-dependent MCSs are disclosed. Input data may be parsed into a plurality of data streams, and spatial processing is performed on the data streams to generate a plurality of spatial streams. An MCS for each data stream is selected independently. The spatial streams are transmitted via multiple transmit antennas. At least one of the techniques of space time block coding (STBC), space frequency block coding (SFBC), quasi-orthogonal Alamouti coding, time reversed space time block coding, linear spatial processing and cyclic delay diversity (CDD) may be performed on the data/spatial streams. An antennal mapping matrix may then be applied to the spatial streams. The spatial streams are transmitted via multiple transmit antennas. The MCS for each data stream may be determined based on a signal-to-noise ratio of each spatial stream associated with the data stream.

Abstract: A method and apparatus for decomposing a channel matrix in a wireless communication system are disclosed. A channel matrix H is generated for channels between transmit antennas and receive antennas. A Hermitian matrix A=HHH or A=HHH is created. A Jacobi process is cyclically performed on the matrix A to obtain Q and DA matrixes such that A=QDAQH. DA is a diagonal matrix obtained by singular value decomposition (SVD) on the A matrix. In each Jacobi transformation, real part diagonalization is performed to annihilate real parts of off-diagonal elements of the matrix and imaginary part diagonalization is performed to annihilate imaginary parts of off-diagonal elements of the matrix after the real part diagonalization. U, V and DH matrixes of H matrix are then calculated from the Q and DA matrices. DH is a diagonal matrix comprising singular values of the H matrix.

Abstract: A method and apparatus for combining space-frequency block coding (SFBC) and frequency shift transmit diversity (FSTD) in a multiple-input multiple-output (MIMO) orthogonal frequency division multiplexing (OFDM) system.

Abstract: A method and apparatus for combining space-frequency block coding (SFBC), spatial multiplexing (SM) and beamforming in a multiple-input multiple-output (MIMO) orthogonal frequency division multiplexing (OFDM) system. The system includes a transmitter with a plurality of transmit antennas and a receiver with a plurality of receive antennas. The transmitter generates at least one data stream and a plurality of spatial streams. The number of generated spatial streams is based on the number of the transmit antennas and the number of the receive antennas. The transmitter determines a transmission scheme in accordance with at least one of SFBC, SM and beam forming. The transmitter transmits data in the data stream to the receiver based on the selected transmission scheme.

Abstract: An apparatus and method is provided for dynamic range power control of a wireless downlink communication signal, such that target signal quality adjustments are held temporarily when it is apparent that transmit power control commands will not produce the desired response at the transmitting station. Comparisons of measured received signals to thresholds are performed to determine whether the transmitting station has either reached the maximum or minimum transmit power, in which case the target signal quality adjustment is controlled accordingly. When normal transmit power is detected, the target signal quality adjustments are allowed to resume as usual.

Abstract: Methods and apparatus for sounding reference signals (SRS) configuration and transmission. The methods include receiving configuration of wireless transmit/receive unit (WTRU)-specific SRS subframes for transmitting SRS and upon receipt of a trigger, transmitting the SRS for a number of antennas. The SRS transmissions may occur in each subframe of a duration of WTRU-specific SRS subframes that start a number of WTRU-specific SRS subframes after a triggering subframe. For multiple SRS transmissions from multiple antennas, cyclic shift multiplexing and different transmission combs may be used. The cyclic shift for an antenna may be determined from a cyclic shift reference value. The cyclic shift determined for each antenna providing a maximum distance between cyclic shifts for the antennas transmitting SRS in a same WTRU-specific subframe. SRS transmissions from multiple antennas in the WTRU-specific subframe may be done in parallel.

Abstract: In an orthogonal frequency division multiplexed (OFDM) multiple-in multiple-out (MIMO) wireless communication system, a method for correcting sampler clock frequency offset in a receiver comprises acquiring the frequency offset and symbol timing in a received signal by the receiver. The estimated value of a fractional offset is computed, and a correction in the frequency domain based upon the estimated value of the fractional offset is performed.

Abstract: A method and apparatus for calibration and channel state feedback to support transmit beamforming in a multiple-input multiple-output (MIMO) system are disclosed. For radio frequency (RF) calibration, a first station (STA) sends a calibration request to a second STA, and the second STA sends a sounding packet to the first STA. The first STA receives the sounding packet, performs at least one channel measurement and performs calibration based on the channel measurement. For channel state feedback, the first STA sends a channel state feedback request to the second STA. The second STA sends a sounding packet to the first STA. The first STA receives the sounding packet and performs at least one channel measurement with the sounding packet. The first STA then calculates a steering matrix for transmit beamforming based on the channel measurement.

Abstract: A base station configured for outer loop power control receives an uplink dedicated channel transmission from a wireless transmit/receive unit. The base station transmits transmit power control commands in response to the received uplink channel transmission and determines if the wireless transmit/receive unit is in a discontinuous transmission mode. The base station adjusts a target SIR based on which transmission mode for the wireless transmit/receive unit is detected. The value for the transmit power control command is derived from the adjusted target SIR.

Abstract: A method is disclosed for tuning a beamformed signal in wireless communications including a plurality of sub-carriers and a plurality of eigenbeams. The method includes adjusting a total gain of each of the plurality of sub-carriers and eigenbeams, and applying the adjusted total gain to each of the sub-carriers and each of the eigenbeams.

Abstract: The downlink (DL) communication of single channel codewords is supported by providing a multiple-input multiple-output (MIMO) transmitter and receiver. The transmitter includes NT transmit antennas for transmitting spatial streams to a receiver having NR receive antennas, a precoder and a space-time or space-frequency matrix construction unit in communication with the precoder and the transmit antennas. The space-time or space-frequency matrix construction unit constructs a matrix that defines a threaded algebraic space-time (TAST) codeword based on a number of virtual antennas, NV, and the number of transmit antennas, NT. The transmitter operates in an open loop mode when no feedback information from the receiver is available, a semi-open loop mode when channel rank information is available, and a closed loop mode when channel state information (CSI) is available.

Abstract: A method and apparatus for optimizing the system capacity of an Orthogonal Frequency Division Multiplexing (OFDM) system that uses with Multiple-Input Multiple-Output (MIMO) antennas. In a receiver, a target quality of service (QoS) metric and reference data rate are set. The target QoS metric may be set to a predetermined value and/or may be adjusted dynamically with respect to packet error rate (PER) by a slow outer-loop control processor. The QoS of received signals are compared to the target QoS. Depending on the comparison, the receiver generates a channel quality indicator (CQI) which is sent to the transmitter. The CQI is a one or two bit indicator which indicates to the transmitter to disable, adjust or maintain data transmission rates of particular sub-carriers, groups of sub-carriers per transmit antenna, or groups of sub-carriers across all transmit antennas. At the transmitter, the transmitted data rate is disabled, adjusted or maintained.

Abstract: Power control for devices having multiple transmit antennas are disclosed, including power control methods for Physical Uplink Control Channel (PUCCH) and Sounding Reference Signal (SRS) transmissions for a wireless transmit/receive unit (WTRU). The PUCCH and SRS power control methods include selecting a multiple input multiple output (MIMO) mode and changing the power of the PUCCH or SRS transmission based on the selected MIMO mode. Another power control method estimates an antenna gain imbalance (AGI) for a WTRU having at least two transmit antennas. The AGI is based on measuring a Reference Signal Received Power (RSRP) on each transmit antenna. Each transmit antenna is then scaled by an AGI scaling factor based on the estimated AGI.

Abstract: A method and apparatus for controlling or determining transmit power of transmissions on more than one component carrier (CC) is disclosed. A WTRU may set a transmit power for each of a plurality of channels mapped to multiple CCs. The channels may include at least one physical uplink shared channel (PUSCH) and may also include at least one physical uplink control channel (PUCCH).

Abstract: A method and apparatus for calibration and channel state feedback to support transmit beamforming in a multiple-input multiple-output (MIMO) system are disclosed. For radio frequency (RF) calibration, a first station (STA) sends a calibration request to a second STA, and the second STA sends a sounding packet to the first STA. The first STA receives the sounding packet, performs at least one channel measurement and performs calibration based on the channel measurement. For channel state feedback, the first STA sends a channel state feedback request to the second STA. The second STA sends a sounding packet to the first STA. The first STA receives the sounding packet and performs at least one channel measurement with the sounding packet. The first STA then calculates a steering matrix for transmit beamforming based on the channel measurement.

Abstract: A method and apparatus for determining uplink power in a wireless transmit receive unit (WTRU). The WTRU operates in a carrier aggregated system. The WTRU is configured to receive a plurality of uplink power parameters indexed to one of a plurality of uplink carriers and receive a transmit power control command indexed to the one of the plurality of uplink carriers. The WTRU is configured to determine a pathloss of the one of the plurality of uplink carriers and determine a transmit power for the one of the plurality of uplink carriers based on the plurality of power parameters, the transmit power control command, and the pathloss.