METHODS AND APPARATUSES FOR FEEDING BACK AND RECEIVING PRECODING MATRIX INDICATOR

摘要

Disclosed are methods and apparatuses for feeding back and receiving a precoding matrix indicator. A user equipment (UE) receives a reference signal sent by a base station; the UE selects in a codebook a precoding matrix for each of N first sub-bands in a system transmission bandwidth according to the reference signal, the codebook comprising at least two precoding matrixes, each of the precoding matrixes being indicated by at least a first precoding matrix indicator (PMI) and a second PMI, each of the N first sub-bands being corresponding to one second PMI, and each of M second sub-bands being corresponding to one first PMI; and the UE feeds back the first PMI corresponding to each of the second sub-bands to the base station, and feeds back the second PMI corresponding to each of the first sub-bands to the base station.