| 主权项 |
1. A method for feeding back channel state information, comprising:
a user equipment (UE) determining channel state information which comprises a first type of Preceding Matrix Indicator (PMI) and a second type of PMI, wherein the first type of PMI is used for indicating an index of a first preceding matrix in a first precoding codebook, the first precoding matrix is used for mapping channel information of a wideband and/or long-term channel, the second type of PMI is used for indicating an index of a second precoding matrix in a second precoding codebook, and the second precoding matrix is used for mapping channel information of a subband and/or short-term channel; and the UE feeding back the channel state information which comprises the first type of PMI and the second type of PMI on a Physical Uplink Shared Channel (PUSCH), to inform a base station of acquiring channel information according to a predetermined function of the first precoding matrix and the second precoding matrix; wherein the channel state information further comprises: Rank Indicator (RI) information and/or Channel Quality Indication (CQI) information; wherein the step of the UE feeding back the channel state information which comprises the first type of PMI and the second type of PMI on the PUSCH comprises: the UE feeding back the first type of PMI and the second type of PMI on the PUSCH using a wideband feedback mode; or, the UE feeding back the first type of PMI and the second type of PMI on the PUSCH using a UE-selected subband feedback mode; or, the UE feeding back the first type of PMI and the second type of PMI using a high layer configured feedback mode; wherein the UE feeding back the first type of PMI and the second type of PMI on the PUSCH using a wideband feedback mode comprises: when RI>a0 and a0 is a positive integer which is greater than or equal to 2, the UE selecting the first precoding matrix corresponding to a subband set from the first stored precoding codebook, and feeding back an index number of the selected first precoding matrix as the first type of PMI of the subband set; when RI>a0 and a0 is a positive integer which is greater than or equal to 2, the UE selecting the second precoding matrix, with a fixed value, corresponding to a subband set from the second stored precoding codebook and not feeding back an index number of the selected second precoding matrix as the second type of PMI of the subband set; wherein the UE feeding back the first type of PMI and the second type of PMI on the PUSCH using a UE-selected subband feedback mode comprises: the UE selecting the first precoding matrix corresponding to a subband set from the first stored precoding codebook, and feeding back an index number of the selected first precoding matrix as the first type of PMI of the subband set; when RI≦a0 and a0 is a positive integer which is greater than or equal to 2, the UE selecting the second precoding matrix corresponding to the subband set from the second stored precoding codebook, and feeding back an index number of the selected second precoding matrix as the second type of PMI of the subband set; and/or, when RI>a0 and a0 is a positive integer which is greater than or equal to 2, the UE selecting the second precoding matrix, with a fixed value, corresponding to the subband set from the second stored precoding codebook, and not feeding back an index number of the selected second precoding matrix as the second type of PMI of the subband set; wherein the UE feeding back the first type of PMI and the second type of PMI using a high layer configured feedback mode comprises: the UE selecting the first precoding matrix corresponding to a subband set from the first stored precoding codebook, and feeding back an index number of the selected first precoding matrix as the first type of PMI of the subband set; when RI≦a0 and a0 is a positive integer which is greater than or equal to 2, the UE selecting the second precoding matrix corresponding to the subband set from the second stored precoding codebook, and feeding back an index number of the selected second precoding matrix as the second type of PMI of the subband set; and/or, when RI>a0 and a0 is a positive integer which is greater than or equal to 2, the UE selecting the second precoding matrix, with a fixed value, corresponding to the subband set from the second stored precoding codebook, and not feeding back an index number of the selected second precoding matrix as the second type of PMI of the subband set. |
