Methods and apparatuses are provided for receiving control information by a terminal. A control channel message is received on a control channel. Control information is extracted from the control channel message. The control information includes a transmission rank and precoding matrix information if a common pilot is used for data demodulation. The control information includes the transmission rank and information about a dedicated pilot if the dedicated pilot is used for the data demodulation.

A method and apparatus for increasing the data rate and providing antenna diversity using multiple transmit antennas utilize a set of bits of a digital signal to generate a codeword. Delay elements may be provided in antenna output channels, or, with suitable code construction, delay may be omitted. n signals represent n symbols of a codeword are transmitted with n different transmit antennas. At the receiver, the noisy received sequence is decoded. The parallel transmission and channel coding enables an increase the data rate over previous techniques, and recovery even under fading conditions. The channel coding may be concatenated with error correction codes under appropriate conditions.

An adaptable orthogonal frequency-division multiplexing system (OFDM) that uses a multiple input multiple output (MIMO) to having OFDM signals transmitted either in accordance with time diversity to reducing signal fading or in accordance with spatial diversity to increase the data rate. Sub-carriers are classified for spatial diversity transmission or for time diversity transmission based on the result of a comparison between threshold values and at least one of three criteria. The criteria includes a calculation of a smallest eigen value of a frequency channel response matrix and a smallest element of a diagonal of the matrix and a ratio of the largest and smallest eigen values of the matrix.

Disclosed is a method for mitigating inter-cell interference. A method for mitigating inter-cell interference can comprise the steps of: a terminal, which is being serviced by means of a fixed cell, receiving from the fixed cell a first signal that is generated on the basis of a first STBC; the terminal, in time resources overlapping the reception time of the first signal, receiving from a moving cell a second signal that is generated on the basis of a second STBC; and the terminal determining a transmission symbol component on the basis of the first signal and an interference component on the basis of the first signal and the second signal.

A simple block coding arrangement is created with symbols transmitted over a plurality of transmit channels, in connection with coding that comprises only simple arithmetic operations, such as negation and conjugation. The diversity created by the transmitter utilizes space diversity and either time or frequency diversity. Space diversity is effected by redundantly transmitting over a plurality of antennas, time diversity is effected by redundantly transmitting at different times, and frequency diversity is effected by redundantly transmitting at different frequencies: Illustratively, using two transmit antennas and a single receive antenna, one of the disclosed embodiments provides the same diversity gain as the maximal-ratio receiver combining (MRRC) scheme with one transmit antenna and two receive antennas. The principles of this invention are applicable to arrangements with more than two antennas, and an illustrative embodiment is disclosed using the same space block code with two transmit and two receive antennas.

A wireless communication system includes a wireless transmit/receive unit (WTRU). The WTRU is configured to generate at least one local codebook based on a baseline codebook, and select a codeword from the local codebook that is associated with feedback.

An apparatus and method are provided for a quantity and size of subbands in a channel state information (CSI) reporting band for flexibility and reduced complexity of terminal addressing. The method includes: determining a channel state information subband size based on a bandwidth part (BWP), determining a quantity of channel state information subbands included in a channel state information reporting band based on (i) a carrier bandwidth (CC bandwidth), (ii) the BWP bandwidth or (iii) a channel state information reference signal (CSI-RS) bandwidth and the channel state information subband size. The method further includes determining an actual quantity of resource blocks included in a starting subband and an actual quantity of resource blocks in an ending subband in the channel state information subband.

In the present invention, disclosed is a method for uplink multi-user transmission in a wireless communication system and an apparatus therefor. Specifically, a method for performing, by a station (STA), uplink (UL) multi-user (MU) transmission in a wireless communication system comprises the steps of: receiving, from an access point (AP), a trigger frame including information for UL MU transmission; and transmitting an UL MU PPDU on the basis of the information for UL MU transmission, wherein the trigger frame is a medium access control (MAC) frame, a MAC header of the trigger frame includes a type field and a subtype field, and the type of the trigger frame may be indicated by the type field and the subtype field.

In a transmission method according to one aspect of the present disclosure, a encoder performs error correction coding on an information bit string to generate a code word. A mapper modulates a first bit string in which the number of bits is the predetermined integral multiple of (X+Y) in the code word using a first scheme, the first scheme being a set of a modulation scheme in which an X-bit bit string is mapped to generate a first complex signal and a modulation scheme in which a Y-bit bit string is mapped to generate a second complex signal, and modulates a second bit string in which the first bit string is removed from the code word using a second scheme different from the first scheme.

Methods and devices are provided for MIMO OFDM transmitter and receivers having odd and/even numbers of transmit antennas. Various methods for pre-coding information bits before space time coding (STC) are described for enabling transmission of information bits over all antennas. Methods of decoding received signals that have been pre-coded and STC coded are also provided by embodiments of the invention. Pilot patterns for downlink and uplink transmission between a base station and one or more wireless terminals for three transmit antenna transmitters are also provided. Variable rate codes are provided that combine various fixed rate codes in a manner that results in codes whose rates are dependent on all the various fixed rate codes that are combined.