| 摘要 |
CSI may be provided for a first device communicating with a second device over a MIMO channel using codewords of a precoding codebook. The first and/or second devices support communications over the MIMO channel using a plurality of transmission layers, and the codewords of the precoding codebook are divided into transmission layer groups. Each transmission layer group is provided for a respective one of the transmission layers. At least first and second pluralities of codewords of the precoding codebook are defined. Each of the first and second pluralities includes codewords from each of the transmission layer groups. During a first TTI, respective performance metrics for the first plurality of codewords are determined based on transmissions received at the first device. During a second TTI, respective performance metrics for the second plurality of codewords are determined based on transmissions received at the first device. |
