METHOD AND DEVICE FOR REPORTING CHANNEL STATE INFORMATION IN WIRELESS COMMUNICATION SYSTEM

• US 20150162966A1
• Filed: 07/02/2013
• Published: 06/11/2015
• Est. Priority Date: 07/02/2012
• Status: Active Grant

• Current Assignee: LG Electronics, Inc. (LG Corporation)
• Original Assignee: LG Electronics, Inc. (LG Corporation)
• Inventors: Kim, Kijun, Park, Jonghyun, Seo, Hanbyul, Park, Hanjun
• Granted Patent: US 9,716,539 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: H04B 17/345 Interference values signal-to-interference ratio [SIR] or carrier-to-interference ratio [CIR] H04B17/336
• CPC Class Codes: H04B 7/0452 Multi-user MIMO systems
• CPC Class Codes: H04B 7/0456 Selection of precoding matrices or codebooks, e.g. using matrices antenna weighting
• CPC Class Codes: H04B 7/0617 for beam forming
• CPC Class Codes: H04B 7/0626 Channel coefficients, e.g. channel state information [CSI]
• CPC Class Codes: H04L 1/20 using signal quality detector
• CPC Class Codes: H04L 5/0048 Allocation of pilot signals, i.e. of signals known to the receiver
• CPC Class Codes: H04L 5/0053 Allocation of signaling, i.e. of overhead other than pilot signals
• CPC Class Codes: H04L 5/0057 Physical resource allocation for CQI
• CPC Class Codes: H04W 24/08 Testing, supervising or monitoring using real traffic

Abstract

A method of reporting channel state information (CSI) on a terminal in which a plurality of CSI processes are configured in a wireless communication system according to an embodiment of the present invention includes: measuring a channel based on a CSI reference signal (RS) resource related to one of the CSI processes; measuring interference based on a CSI-interference measurement (IM) resource related to the CSI process; determining CSI based on the measured channel and the measured interference; and reporting the CSI through an uplink channel, wherein a codebook for reporting the CSI, which is used for determining the CSI, is one of two or more codebooks that correspond independently to each of the CSI processes.

Claims

1. A method for reporting channel state information (CSI) by a user equipment (UE) having a plurality of CSI processes in a wireless communication system, the method comprising:

measuring a channel based on a CSI-reference signal (CSI-RS) resource associated with one CSI process of the plurality of CSI processes;

measuring an interference based on a CSI-interference measurement (CSI-IM) resource associated with the one CSI process;

determining the CSI based on the measured channel and interference; and

reporting the CSI over an uplink channel,

wherein a codebook for the reporting of the CSI is one of two or more codebooks each independently corresponding to each of the plurality of CSI processes, the codebook being used in determining the CSI.

2. The method according to claim 1, wherein the determining comprises:

determining a precoding matrix from the codebook for the reporting of the CSI corresponding to the one CSI process.

3. The method according to claim 1, wherein the two or more codebooks reflect channel environments depending on different beamformings.

4. The method according to claim 1, wherein the CSI-IM resource is indicated by either a CSI-IM resource configuration including subframes having same interference characteristics or a CSI-IM resource configuration including subframes having different interference characteristics.

5. The method according to claim 1, wherein the UE receives information about whether or not averaging interferences measured in a plurality of subframes corresponding to the CSI-IM resource is allowed.

6. The method according to claim 5, wherein the information is delivered through radio resource control (RRC) signaling.

7. The method according to claim 1, wherein a signal for a Multi User-Multi Input Multi Output (MU-MIMO)-paired UE is transmitted in a portion of subframes corresponding to the CSI-IM resource.

8. The method according to claim 7, wherein the signal for the MU-MIMO paired UE is either a PDSCH for the MU-MIMO-paired UE or a dummy signal obtained by applying a precoding matrix associated with the MU-MIMO-paired UE.

9. The method according to claim 1, wherein the CSI-IM resource is indicated by either a CSI-IM resource configuration including subframes having same channel characteristics or a CSI-IM resource configuration including subframes having different channel characteristics.

10. The method according to claim 9, wherein the different channel characteristics result from change of an antenna virtualization matrix used in transmitting a CSI-RS corresponding to the CSI-RS resource.

11. The method according to claim 1, wherein the measuring of the channel is performed using a non-zero power CSI-RS among the CSI-RS resource, and the measuring of the interference is performed using a zero-power CSI-RS among the CSI-IM resource.

12. The method according to claim 1, wherein the uplink channel is one of a physical uplink shared channel (PUSCH) and a physical uplink control channel (PUCCH).

13. A user equipment (UE) having a plurality of channel state information (CSI) processes configured in a wireless communication system, the UE comprising:

a receive module; and

a processor,

wherein the processor is configured to;

measure a channel based on a CSI-reference signal (CSI-RS) resource associated with one CSI process of the plurality of CSI processes;

measure an interference based on a CSI-interference measurement (CSI-IM) resource associated with the one CSI process;

determine the CSI based on the measured channel and interference; and

report the CSI over an uplink channel,

wherein a codebook for reporting of the CSI is one of two or more codebooks each independently corresponding to each of the plurality of CSI processes, the codebook being used in determining the CSI.