Techniques for channel state information feedback in wireless communication system
Methods for a User Equipment (UE) to transmit Channel Quality Index (CQI) feedback information, and an indicator in feedback information, to an evolved Node B (eNB) in a wireless communication system, and apparatuses therefore, are provided. A method for a UE to transmit CQI feedback information to eNB in a wireless communication system, includes obtaining one or more Transmission Points Configurations for Coordinated MultiPoint (CoMP) (TPCCs), each TPCC including a unique combination of one or more cells in a CoMP measurement set, estimating a channel for one or more cells in the CoMP measurement set, computing a CQI for each of at least one of the one or more TPCCs, each CQI being computed using one or more estimated channels that correspond to the combination of one or more cells included in a corresponding TPCC, generating CQI feedback information based on the one or more CQIs, and transmitting the CQI feedback information.
1. A method for a User Equipment (UE) to transmit Channel Quality Index (CQI) feedback information to an evolved Node B (eNB) in a wireless communication system, the method comprising:
obtaining a plurality of Transmission Points Configurations for Coordinated MultiPoint (CoMP) (TPCCs), each TPCC including a unique combination of one or more cells in a CoMP measurement set, wherein the plurality of TPCCs comprises each possible combination including an anchor cell of the cells in the CoMP measurement set;
estimating a channel for one or more cells in the CoMP measurement set;
computing a CQI for each of at least one of the TPCCs, each CQI being computed using one or more estimated channels that correspond to the combination of one or more cells included in a corresponding TPCC;
generating CQI feedback information based on the one or more CQIs; and
transmitting the CQI feedback information.
2. The method of claim 1 , wherein the obtaining of the TPCCs comprises receiving a message from the eNB identifying the TPCCs, wherein the TPCCs are semi-statistically configured by the eNB.
3. The method of claim 1 , wherein the obtaining of the TPCCs comprises determining the TPCCs.
4. The method of claim 1 , further comprising:
receiving a message from the eNB including a number M,
wherein the obtaining of the TPCCs comprises determining the M best TPCCs, wherein the M best TPCCs are determined based on one or more performance metrics related to received signal quality.
5. The method of claim 1 , wherein each of the TPCCs corresponds to an indicator, and wherein the obtaining of the TPCCs comprises receiving an indicator corresponding to a TPCC selected by the eNB.
6. The method of claim 1 , wherein the CQI feedback information comprises a reference CQI and one or more differential CQIs, wherein the one or more differential CQIs are differentially encoded relative to the reference CQI.
7. A User Equipment (UE) apparatus for transmitting Channel Quality Index (CQI) feedback information to an evolved Node B (eNB) in a wireless communication system, the apparatus comprising:
a receiver for receiving signals from one or more cells in a CoMP measurement set;
a transmitter for transmitting signals to at least one cell; and
a controller for controlling the receiver and transmitter, and for controlling to obtain a plurality of Transmission Points Configurations for Coordinated MultiPoint (CoMP) (TPCCs), each TPCC including a unique combination of one or more cells in a CoMP measurement set, for controlling to estimate a channel for one or more cells in the CoMP measurement set, the plurality of TPCCs comprising each possible combination including an anchor cell of the cells in the CoMP measurement set, for controlling to compute a CQI for each of at least one of the TPCCs, each CQI being computed using one or more estimated channels that correspond to the combination of one or more cells included in a corresponding TPCC, for controlling to generate CQI feedback information based on the one or more CQIs, and for controlling the transmitter to transmit the CQI feedback information.
8. The apparatus of claim 7 , wherein the controller when controlling to obtain the TPCCs, controls to receive a message from the eNB identifying the TPCCs, wherein the TPCCs are semi-statistically configured by the eNB.
9. The apparatus of claim 7 , wherein the controller when controlling to obtain the TPCCs, controls to determine the TPCCs.
10. The apparatus of claim 7 , wherein each of the TPCCs corresponds to an indicator, and wherein the controller when controlling to obtain the TPCCs, controls to receive an indicator corresponding to a TPCC selected by the eNB.
11. The apparatus of claim 7 , wherein the controller controls to receive a message from the eNB including a number M, and wherein the controller when controlling to obtain the TPCCs, controls to determine the M best TPCCs, wherein the M best TPCCs are determined based on one or more performance metrics related to received signal quality.
12. The apparatus of claim 7 , wherein the CQI feedback information comprises a reference CQI and one or more differential CQIs, wherein the one or more differential CQIs are differentially encoded relative to the reference CQI.