Method and device for transmitting channel state information in wireless communication system

• US 9,509,471 B2
• Filed: 08/20/2013
• Issued: 11/29/2016
• Est. Priority Date: 08/21/2012
• Status: Active Grant

• Current Assignee: LG Electronics, Inc. (LG Corporation)
• Original Assignee: LG Electronics, Inc. (LG Corporation)
• Inventors: Kim, Hyungtae, Park, Jonghyun, Kim, Kijun, Kim, Eunsun
• Primary Examiner(s): LY, ANH VU H
• Application Number:
  US14/384,137
• Publication Number:
  US 20150063177A1
• Time in Patent Office: 1,197 Days
• Field of Search: None
• US Class Current: 1/1
• CPC Class Codes: H04B 7/024 Co-operative use of antennas of several sites, e.g. in co-ordinated multipoint or co-operative multiple-input multiple-output [MIMO] systems
• CPC Class Codes: H04L 5/0023 Time-frequency-space
• CPC Class Codes: H04L 5/0035 Resource allocation in a cooperative multipoint environment
• 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 5/14 Two-way operation using the same type of signal, i.e. duplex
• CPC Class Codes: H04L 5/1469 using time-sharing
• CPC Class Codes: H04W 24/10 Scheduling measurement reports ; Arrangements for measurement reports

Abstract

The present invention relates to a wireless communication system. A method for transmitting channel state information (CSI) by a user equipment in a wireless communication system includes receiving a CSI-reference signal (CSI-RS), determining overhead of a common reference signal (CRS) resource element based on the same antenna port number as an antenna port number associated with the CSI-RS, and transmitting the CSI calculated based on the CSI-RS and the overhead of the CRS resource element.

Claims

1. A method for transmitting Channel State Information (CSI) in a wireless access system, the method performed by a user equipment and comprising:

receiving a Channel State Information-Reference Signal (CSI-RS);

assuming an overhead of Common Reference Signal Resource Elements (CRS REs) to be based on a number of antenna ports which is the same as a number of antenna ports associated with the CSI-RS; and

transmitting the CSI based on the assumed overhead of CRS REs.

2. The method of claim 1, further comprising:

receiving CSI configuration information for reporting the CSI.

3. The method of claim 2, wherein the CSI configuration information is configured to report a channel quality indicator (CQI) without reporting a precoding matrix indicator (PMI) and a rank indicator (RI).

4. The method of claim 2, wherein the CSI configuration information is transmitted using Radio Resource Control (RRC) signaling.

5. The method of claim 1, wherein the number of antenna ports associated with the CSI-RS is configured less than or equal to 4.

6. The method of claim 1, wherein the CSI indicates a channel state in a Time Division Multiplexing (TDD) system of satisfying a channel reciprocity.

7. A method for receiving Channel State Information (CSI) in a wireless access system, the method performed by a base station and comprising:

transmitting a Channel State Information-Reference Signal (CSI-RS); and

receiving the CSI generated based on an overhead of Common Reference Signal Resource Elements (CRS REs),

wherein the overhead of the CRS REs is assumed to be based on a number of antenna ports which is the same as a number of antenna ports associated with the CSI-RS.

8. The method of claim 7, further comprising:

transmitting CSI configuration information for reporting the CSI.

9. The method of claim 8, wherein the CSI configuration information is configured to report a channel quality indicator (CQI) without reporting a precoding matrix indicator (PMI) and a rank indicator (RI).

10. The method of claim 8, wherein the CSI configuration information is transmitted using Radio Resource Control (RRC) signaling.

11. The method of claim 7, wherein the number of antenna ports associated with the CSI-RS is configured less than or equal to 4.

12. The method of claim 7, wherein the CSI indicates a channel state in a Time Division Multiplexing (TDD) system of satisfying a channel reciprocity.

13. A user equipment for transmitting Channel State Information (CSI) in a wireless access system, the user equipment comprising:

a radio frequency (RF) unit; and

a processor configured to;

receive a Channel State Information-Reference Signal (CSI-RS);

assume an overhead of Common Reference Signal Resource Elements (CRS REs) to be based on a number of antenna ports which is the same as a number of antenna ports associated with the CSI-RS; and

transmit the CSI based on the assumed overhead of CRS REs.

14. A base station for receiving Channel State Information (CSI) in a wireless access system, the base station comprising:

a radio frequency (RF) unit; and

a processor configured to;

transmit a Channel State Information-Reference Signal (CSI-RS); and

receive the CSI generated based on an overhead of Common Reference Signal Resource Elements (CRS REs),

wherein the overhead of the CRS REs is assumed to be based on a number of antenna ports which is the same as a number of antenna ports associated with the CSI-RS.