Patent ID: 9496942
Filing Date: 2016-11-15
CPC Classification: H04B,H04L,H04W

Claim Text:
1. A method of reporting channel state information (CSI) by a user equipment (UE), the method comprising: transmitting a first type physical uplink control channel (PUCCH) report for 8 transmission antenna ports in which a rank indicator (RI) and a first precoding matrix index (PMI) are jointly encoded; calculating a channel quality indicator (CQI) and a second PMI based on the RI and the first PMI, a combination of the first PMI and the second PMI indicating a single precoding matrix; and transmitting a second type PUCCH report for the 8 transmission antenna ports including the CQI and the second PMI, wherein when the RI is lower than a predetermined value, the first PMI is selected from a subset of a codebook for the RI, and wherein when the first type PUCCH report in which the RI and the first PMI are jointly encoded collides with the second type PUCCH report including the CQI and the second PMI in a same subframe, the second type PUCCH report is dropped at the same subframe.