Patent ID: 9585044
Date: 2017-02-28
CPC Classifications: H04B,H04L,H04W

Claim:
1. A method of transmitting channel state information (CSI) for a CoMP (coordinated multi-point transmission and reception) set comprising a plurality of eNodeBs, the method performed by a user equipment (UE) and comprising; receiving, from respective eNodeBs of the plurality of eNodeBs of the CoMP set, channel state information reference signals (CSI-RSs) according to a single CSI-RS configuration for the CoMP set, wherein the single CSI-RS configuration includes mapping information between CSI-RS resource elements and antenna port(s) of a respective one of the plurality of eNodeBs; receiving, from the serving eNodeB, information about CSI-RS transmission power used for each of a plurality of antenna ports of the plurality of eNodeBs to transmit CSI-RSs; calculating the CSI for the CoMP set using the received information about CSI-RS transmission power and the received CSI-RSs, the calculated CSI including multiple channel quality indicators (CQIs) and a single precoding matrix indicator (PMI) corresponding to the single CSI-RS configuration, wherein each of the multiple CQIs corresponds to respective one of the plurality of eNodeBs of the CoMP set and the single PMI is a precoding matrix that is closest to an optimum precoding matrix obtained by compensating phase differences for the received CSI-RSs; and transmitting the calculated CSI to the serving eNodeB.