METHOD AND APPARATUS FOR EFFICIENT FEEDBACK IN A WIRELESS COMMUNICATION SYSTEM SUPPORTING MULTIPLE ANTENNA

摘要

A method for transmitting channel status information (CSI) via uplink in a wireless communication system includes transmitting a first precoding matrix indicator (PMI) and a second PMI at a subframe. A subsampled codebook for each of a precoding codebook for Rank-1 and a precoding codebook for Rank-2 is determined based on at least the first PMI or the second PMI. In case of the Rank-1 or the Rank-2, a number of elements for the first PMI is 8.

主权项

1. A method of transmitting channel state information (CSI) by a user equipment in a wireless communication system, the method comprising:
measuring CSI regarding at least one of a rank indication (RI), a precoding matrix indicator (PMI) and a channel quality indicator (CQI); and transmitting the CQI and the PMI via a physical uplink control channel (PUCCH), wherein in the measurement of the CSI, when a value of the RI is lower than a first value and the PMI is indicated by a first PMI value and a second PMI value in a codebook for 8-transmission antennas, at least one of the first PMI value and the second PMI value is obtained from a sub-sampled codebook of the codebook.