Method and apparatus for reporting channel state information in wireless communication system

• US 10,122,481 B2
• Filed: 04/16/2014
• Issued: 11/06/2018
• Est. Priority Date: 04/16/2013
• Status: Active Grant

• Current Assignee: LG Electronics, Inc. (LG Corporation)
• Original Assignee: LG Electronics, Inc. (LG Corporation)
• Inventors: Seo, Inkwon, Lee, Seungmin, Seo, Hanbyul
• Primary Examiner(s): Nawaz, Asad
• Assistant Examiner(s): Harley, Jason
• Application Number:
  US14/782,561
• Publication Number:
  US 20160050648A1
• Time in Patent Office: 1,665 Days
• Field of Search: 370252, 370329
• CPC Class Codes: H04B 17/382 for resource allocation, admission control or handover
• CPC Class Codes: H04B 7/0626 Channel coefficients, e.g. channel state information [CSI]
• CPC Class Codes: H04L 5/0057 Physical resource allocation for CQI
• CPC Class Codes: H04L 5/0073 Allocation arrangements that take into account other cell interferences for intercell interference mitigation or co-ordination in orthogonal multiplex systems H04J11/005
• CPC Class Codes: H04L 5/0091 Signaling for the administration of the divided path
• CPC Class Codes: H04L 5/1469 using time-sharing
• CPC Class Codes: H04W 24/10 Scheduling measurement reports ; Arrangements for measurement reports
• CPC Class Codes: H04W 72/20 Control channels or signalling for resource management
• CPC Class Codes: H04W 72/23 in the downlink direction of a wireless link, i.e. towards a terminal
• CPC Class Codes: H04W 72/53 based on regulatory allocation policies
• CPC Class Codes: H04W 72/541 using the level of interference

Abstract

One embodiment of the present invention provides a method for reporting channel state information (CSI) of a terminal in a wireless communication system, comprising the steps of: receiving a downlink signal comprising an uplink grant; when a CSI request field contained in the downlink signal triggers a CSI report, deriving a CQI value on the basis of a PDSCH transmission block in a CSI reference resource; and carrying out a CSI report including the CQI value in subframe n, wherein the CSI reference resource is the last subframe that is not later than a subframe which is four subframes before subframe n.

Claims

1. A method for performing Channel State Information (CSI) reporting by a User Equipment (UE) in a wireless communication system, the method comprising:

receiving a first uplink-downlink (UL-DL) configuration indicating whether each of a plurality of subframes is configured as a UL subframe or a DL subframe;

receiving a second UL-DL configuration to reconfigure a UL subframe indicated by the first UL-DL configuration to a DL subframe indicated by the second UL-DL configuration;

receiving, by the UE, a downlink signal including a Downlink Control Information (DCI) format including a CSI request field;

determining, by the UE, a Channel Quality Indicator (CQI) value based on a Physical Downlink Shared Channel (PDSCH) transport block in a CSI reference resource when the CSI request field triggers CSI reporting; and

performing, by the UE, CSI reporting including the CQI value in a subframe n, where n is an arbitrary identifier,

wherein the CSI reference resource is a last valid subframe among subframes which precede the subframe n by four subframes,

wherein the CSI reference resource is a DL subframe indicated by the first UL-DL configuration, and

wherein the DL subframe indicated by the first UL-DL configuration and that is the CSI reference resource is not reconfigured by the second UL-DL configuration.

2. The method according to claim 1, wherein, if two or more subframe sets are configured for the UE, a subframe set related to CSI reporting is indicated by a CSI request field included in the downlink signal.

3. The method according to claim 2, wherein the last subframe is included in the subframe set related to CSI reporting.

4. The method according to claim 3, wherein at least one CSI process is configured for the UE.

5. The method according to claim 4, wherein the CSI process includes a CSI-Reference Signal (CSI-RS) resource for signal measurement and two CSI-Interference Measurement (IM) resources for interference measurement.

6. The method according to claim 2, wherein the CSI reference resource corresponds to a subframe set indicated by the CSI request field.

7. The method according to claim 1, wherein the UE has capabilities of receiving a downlink signal in a subframe different from a subframe used in an uplink-downlink configuration indicated by system information.

8. The method according to claim 2, wherein a relationship between a value of the CSI request field and the two or more subframe sets is indicated by a Radio Resource Control (RRC) signaling.

9. The method according to claim 1, wherein a transmission mode configured for the UE is one of transmission modes 1 to 10.

10. The method according to claim 1, wherein the DCI includes the uplink grant.

11. The method according to claim 1, wherein CSI reporting is transmitted over a Physical Uplink Shared Channel (PUSCH).

12. A User Equipment (UE) for which a plurality of Channel State Information (CSI)-Reference Signal (RS) configurations is configured in a wireless communication system, the UE comprising:

a reception module; and

a processor,

wherein the processor is configured to

receive a first uplink-downlink (UL-DL) configuration indicating whether each of a plurality of subframes is configured as a UL subframe or a DL subframe,

receive a second UL-DL configuration to reconfigure a UL subframe indicated by the first UL-DL configuration to a DL subframe indicated by the second UL-DL configuration,

receive a downlink signal including a Downlink Control Information (DCI) format including a CSI request field,

determine a Channel Quality Indicator (CQI) value based on a Physical Downlink Shared Channel (PDSCH) transport block in a CSI reference resource when the CSI request field triggers CSI reporting, and

perform CSI reporting including the CQI value in a subframe n, where n is an arbitrary identifier,

wherein the CSI reference resource is a last valid subframe among subframes which precede the subframe n by four subframes,

wherein the CSI reference resource is a DL subframe indicated by the first UL-DL configuration, and

wherein the DL subframe indicated by the first UL-DL configuration and that is the CSI reference resource is not reconfigured by the second UL-DL configuration.