LOW OVERHEAD PMI AND CQI FEEDBACK AND PAIRING SCHEMES FOR MU-MIMO

摘要

A method is provided for searching for a pairing PMI including estimating a MIMO wireless propagation channel from an access point transmitter to a receiver at a UE; quantizing the estimated channel with a codebook consisting of a plurality of codewords, the result being an actual SU-MIMO PMI currently applicable to the UE; estimating the channel quality corresponding to the actual SU-MIMO PMI, resulting in at least one CQI for the UE; constructing a plurality of subsets from a codebook of codewords, wherein each subset comprises potential MU-MIMO PMIs that represent channels that have reduced interference with a channel represented by one of the potential SU-MIMO PMIs; associating each potential SU-MIMO PMI with the subset that comprises the potential MU-MIMO PMIs that represent channels that have reduced interference with the channel represented by that potential SU-MIMO PMI; searching for an appropriate pairing PMI and the associated CQI for the UE.