| 摘要 |
A method and apparatus for optimizing the system capacity of an Orthogonal FrequencyDivision Multiplexing (OFDM) system that uses with Multiple-Input Multiple-Output(MIMO) antennas. In a receiver, a target quality of service (QoS) metric and referencedata rate are set. The target QoS metric may be set to a predetermined value and/ormay be adjusted dynamically with respect to packet error rate (PER) by a slow outer-loopcontrol processor. The QoS of received signals are measured and compared to thetarget QoS. Depending on the comparison, the receiver generates a channel qualityindicator (CQI) which is sent back to the transmitting transmitter. The CQI isa one or two bit indicator which indicates to the transmitter to disable, adjustor maintain data transmission rates of particular sub-carriers, groups of sub-carriersper transmit antenna, or groups of sub-carriers across all transmit antennas.At the transmitter, the transmitted data rate is disabled, adjusted or maintained.At the receive r, the target QoS metric and reference data rate are adjusted accordingly.This process is repeated for each data frame of each sub-carrier group. |
