Systems and methods for OFDM channelization are provided that allow for the coexistence of sub-band channels and diversity channels. Methods of defining diversity sub-channels and sub-band sub-channels are provided and systematic channel definition and labeling schemes are provided.

Systems and methods for OFDM channelization are provided that allow for the coexistence of sub-band channels and diversity channels. Methods of defining diversity sub-channels and sub-band sub-channels are provided and systematic channel definition and labeling schemes are provided.

A method and apparatus for improving performance in communication systems is provided. In one implementation, initial encoded data that has been encoded with a rateless code is received. A quality metric is determined for a communication medium on which the initial encoded data has been received. A modulation scheme used in sending the initial encoded data on the communication medium is identified. An estimate is determined, based on the identified modulation scheme and the determined quality metric, of an amount of mutual information being received per unit of received encoded data. An amount of mutual information being received is determined, based on the determined estimate.

Automatic retransmission in communications systems. In one embodiment, a portion of data is identified to be retransmitted based on feedback information indicating a negative acknowledgement (NACK) during a cyclic redundancy check (CRC) on a previous transmission of the portion of data. A retransmission mode is selected for the portion of data, from at least a first mode that retransmits the portion of data on at least a first transmitter antenna while transmitting new data on at least a second transmitter antenna, based on first desired transmission characteristics; and a second mode that retransmits the portion of data simultaneously on at least the first and second transmitter antennas, based on second desired transmission characteristics.

Transmission of uplink control message for a wireless system. The uplink control message may be encoded according to one of multiple possible schemes. The choice of encoding scheme may be made based on the control message size and/or based on the available transmission resources and/or based on the detection scheme used on the receiving end. A modulation scheme may also be selected based on such factors. CDM may be used for certain control messages. Block code encoding, such as Reed-Muller encoding may be used for certain control messages. Different transmission resources may be allocated for different control message uses. The encoding specifics may be selected to obtain a certain hamming distance and/or size of the encoded message or based on other factors.

A MIMO ARC transmitter derives demux streams (15, 20) carrying different parts of the information, at given data rates, processes each demux stream by coding and modulation (25, 30) before transmission over the channels, and varies (50, 165) the coding or modulation according to channel conditions, and controls the data rates (50, 155) according to conditions of the channels independently of the variations in coding and modulation. The separate control of processing and of data rates for each demux stream can provide a better balance of rapid response to changing conditions and efficiency in less rapidly changing conditions. The frequency of updating the processing can be limited since these take more time to adapt in the receiver. Sensitivity to rapid changes can be achieved by the data rate changes since these involve less overhead than changes in the processing.

Systems and methods for OFDM channelization are provided that allow for the coexistence of sub-band channels and diversity channels. Methods of defining diversity sub-channels and sub-band sub-channels are provided and systematic channel definition and labeling schemes are provided.

In performing SVD-MIMO transmission, a set-up procedure is simplified while assuring a satisfactory decoding capability with a reduced number of antennas. A transmitter estimates channel information based on reference signals sent from a receiver, determines a transmit antenna weighting coefficient matrix based on the channel information, calculates a weight to be assigned to each of components of a multiplexed signal, and sends, to the receiver, training signals for respective signal components, the training signals being weighted by the calculated weights. On the other hand, the receiver determines a receive antenna weighting coefficient matrix based on the received training signals.

The present invention relates to a method and a device for estimating a channel of a terminal in a wireless communication system that supports multiple antennas. Particularly, the method comprises the steps of receiving a channel state information-reference signal (CSI-RS) for a plurality of first domain antennas and a cell-specific reference signal (CRS) for a plurality of second domain antennas, and estimating the all of the channels on the basis of a first channel for the first domain antennas estimated from the CSI-RS and a second channel for the second domain antennas estimated from the CRS.

A method for indicating a combination between a codeword and a layer in a MIMO communication, system, a layer mapping method, and a data transmission method using the same are disclosed. A minimum number of codeword-layer mapping combinations from among all available combinations based on the' numbers of all codewords and all layers are pre-defined in consideration of a ratio of a codeword to a layer, a reception performance of a receiver, and reduction of combinations, so that a data transmission method using the predefined combinations is implemented. If a.specific one codeword is mapped to at least two layers, a diversity gain can be acquired.