Patent ID: 8855002

Claim:
An apparatus for feeding back channel information to a Base Station (BS) connected to one or more User Equipments (UEs), the apparatus generating and feeding back channel state information considering inter-UE interference due to an access of an additional UE, the apparatus comprising: a Channel Status Index-Reference Signal (CSI-RS) receiver for receiving a CSI-RS from the BS; a channel estimator for estimating a channel by using the received CSI-RS; a Demodulation Reference Signal (DM-RS) receiver for receiving a DM-RS of the additional UE; a precoder estimator for estimating a type of a precoder (PC) of the corresponding additional UE based on the received DM-RS of the additional UE and a channel estimation result by the channel estimator; an MAI (Multiple Access Interference) determiner for determining MAI based on information on the precoder of the additional UE estimated by the precoder estimator and the channel estimation result by the channel estimator; and a state information generating/transmitting unit for generating and feeding back channel state information reflecting interference generated due to the additional UE according to the MAI.