Patent ID: 9698887
Date: 2017-07-04
CPC Classifications: H04B

Claim:
1. A method for channel state information (CSI) reporting by a base station, comprising: determining a codebook used by a wireless communication device for a CSI report corresponding to four transmit antenna (4Tx) transmissions from the base station, wherein the codebook has a dual codebook structure comprising a block-diagonal grid of beams structure W=W receiving the CSI report as a type 5 report in physical uplink control channel (PUCCH) mode 1-1, submode 1, wherein the type 5 report uses 1 bit to represent a rank indicator for maximum 2-layer spatial multiplexing and 2 bits to represent the rank indicator for maximum 4-layer spatial multiplexing; and decoding the CSI report using the codebook.