摘要 |
An evolved Node B (eNB) in a 3GPP LTE-based network receives Channel State Information-Reference Signal (CSI-RS) from a User Equipment (UE) that is configured with Precoder Matrix Indicator (PMI) disabled. A channel is estimated between the eNB and the UE for link adaptation in Transmission Mode 9 (TM9) based on CSI-RS by the UE and SRS by the eNB. CQI is calculated at UE such that if a number of CSI-RS antenna ports equals one, TM9 transmission from the eNB to the UE uses a predetermined single antenna port. If the number of CSI-RS antenna ports equals two, TM9 transmission from the eNB to the UE uses transmit diversity. If the number of CSI-RS antenna ports does not equal one or two, TM9 transmission from the eNB to the UE uses spatial multiplexing based on a rank-1 precoder that is determined from a wideband channel covariance matrix R. |