INTER-CELL INTERFERENCE COORDINATION IN A WIRELESS COMMUNICATION SYSTEM

• US 20130223258A1
• Filed: 09/26/2011
• Published: 08/29/2013
• Est. Priority Date: 09/28/2010
• Status: Active Grant

• Current Assignee: LG Electronics, Inc. (LG Corporation)
• Original Assignee: LG Electronics, Inc. (LG Corporation)
• Inventors: Seo, Hanbyul, Lee, Daewon, Kim, Byounghoon, Kim, Kijun, Seo, Inkwon
• Granted Patent: US 9,742,546 B2
• Time in Patent Office: Days
• US Class Current: 370/252
• CPC Class Codes: H04B 7/0682 using phase diversity (e.g. phase sweeping)
• CPC Class Codes: H04B 7/084 Equal gain combining, only phase adjustments antenna beam scanning or forming by phase or amplitude control H01Q3/26, e.g. phased arrays
• CPC Class Codes: H04L 1/0026 Transmission of channel quality indication
• CPC Class Codes: H04L 5/0032 Distributed allocation, i.e. involving a plurality of allocating devices, each making partial allocation
• 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: H04W 16/32 Hierarchical cell structures
• CPC Class Codes: H04W 24/02 Arrangements for optimising operational condition
• CPC Class Codes: H04W 24/10 Scheduling measurement reports ; Arrangements for measurement reports
• CPC Class Codes: H04W 52/243 taking into account interferences

Abstract

Disclosed herein is a wireless communication system. More particularly, disclosed herein is a method and apparatus for coordinating and reducing inter-cell interference in a wireless communication system. A method of transmitting channel state information (CSI) measurement resource information by a base station includes determining first and second subframe sets, in which CSI measurement will be performed, among a plurality of downlink subframes, transmitting information indicating the first and second subframe sets to a terminal, and receiving the CSI of each of the first and second subframe sets from the terminal. A subframe belonging to the first subframe set and a subframe belonging to the second subframe set do not overlap, and some of the plurality of subframes do not belong to either of the first and second subframe sets.

Claims

1. A method of transmitting channel state information (CSI) measurement resource information by a base station, comprising:

determining first and second subframe sets, in which CSI measurement will be performed, among a plurality of downlink subframes;

transmitting information indicating the first and second subframe sets to a terminal; and

receiving the CSI of each of the first and second subframe sets from the terminal,

wherein a subframe belonging to the first subframe set and a subframe belonging to the second subframe set do not overlap, and

wherein some of the plurality of subframes do not belong to either of the first and second subframe sets.

2. The method according to claim 1, wherein the base station determines the first and second subframe sets using information indicating a subset of blank subframes of a neighbor cell.

3. The method according to claim 1, wherein the first subframe set includes a subframe in which a probability of being set as a blank subframe by a neighbor cell is higher than that of the second subframe set.

4. A method of performing channel state information (CSI) measurement by a terminal, comprising:

receiving, from a base station, information indicating first and second subframe sets, in which the CSI measurement will be performed, among a plurality of downlink subframes;

performing CSI measurement with respect to each of the first and second subframe sets; and

transmitting the CSI to the base station,

wherein a subframe belonging to the first subframe set and a subframe belonging to the second subframe set do not overlap, and

wherein some of the plurality of subframes do not belong to either of the first and second subframe sets.

5. A base station for transmitting channel state information (CSI) measurement resource information, comprising:

a reception module configured to receive an uplink signal from a terminal;

a transmission module configured to transmit a downlink signal to the terminal; and

a processor configured to control the base station including the reception module and the transmission module,

wherein the processor is configured to;

determine first and second subframe sets, in which CSI measurement will be performed, among a plurality of downlink subframes;

transmit information indicating the first and second subframe sets to the terminal through the transmission module; and

receive the CSI of each of the first and second subframe sets from the terminal through the reception module,

wherein a subframe belonging to the first subframe set and a subframe belonging to the second subframe set do not overlap, and

wherein some of the plurality of subframes do not belong to either of the first and second subframe sets.

6. A terminal for performing channel state information (CSI) measurement, comprising:

a reception module configured to receive a downlink signal from a base station;

a transmission module configured to transmit an uplink signal to the base station; and

a processor configured to control the terminal including the reception module and the transmission module,

wherein the processor is configured to;

receive, from the base station, information indicating first and second subframe sets, in which the CSI measurement will be performed, among a plurality of downlink subframes through the reception module;

perform the CSI measurement with respect to each of the first and second subframe sets; and

transmit the CSI to the base station through the transmission module,

wherein a subframe belonging to the first subframe set and a subframe belonging to the second subframe set do not overlap, and

wherein some of the plurality of subframes do not belong to either of the first and second subframe sets.

7. A method of setting measurement resources by a first base station, comprising:

receiving information about setting of a blank subframe of a second base station among a plurality of subframes; and

setting resources in which a terminal will perform measurement using the information about setting of the blank subframe of the second base station,

wherein the information about setting of the blank subframe of the second base station includes first and second bitmaps,

wherein the first bitmap indicates blank subframes and non-blank subframes, and

wherein the second bitmap indicates a subset of subframes indicated as the blank subframes by the first bitmap.

8. The method according to claim 7, wherein:

each of the blank subframes of the second base station indicated by the first bitmap belongs to any one of a first group or a second group,

the first group includes subframes indicated by the second bitmap as belonging to a subset of blank subframes, and

the second group includes subframes indicated by the second bitmap as not belonging to a subset of blank subframes.

9. The method according to claim 8, wherein a probability of the second base station setting a subframe belonging to the first group to a blank subframe is different from a probability of the second base station setting a subframe belonging to the second group to a blank subframe.

10. The method according to claim 9, wherein the probability of the second base station setting the subframe belonging to the first group to the blank subframe is higher than the probability of the second base station setting the subframe belonging to the second group to the blank subframe.

11. The method according to claim 7, wherein the setting of the resources is performed by the first base station using a subset of blank subframes of the second base station indicated by the second bitmap.

12. A base station of a cell which is subject to interference, which sets measurement resources, comprising:

a reception module configured to receive a signal from a base station of a cell which causes interference;

a transmission module configured to transmit a signal to the base station of the cell which causes interference; and

a processor configured to control the base station of the cell which is subject to interference, which includes the reception module and the transmission module,

wherein the processor is configured to;

receive information about setting of a blank subframe of the base station of the cell which causes interference among a plurality of subframes through the reception module; and

set resources in which a terminal will perform measurement using the information about setting of the blank subframe of the base station of the cell which causes interference,

wherein the information about setting of the blank subframe of the base station of the cell which causes interference includes first and second bitmaps,

wherein the first bitmap indicates blank subframes and non-blank subframes, and

wherein the second bitmap indicates a subset of subframes indicated as the blank subframes by the first bitmap.

13. A method of transmitting information indicating resources from a first base station to a second base station, comprising:

determining a downlink subframe which cannot be used by the first base station due to inter-cell interference among a plurality of downlink subframes; and

transmitting information indicating the determined downlink subframe to the second base station,

wherein the first base station is a base station of a cell which is subject to interference and the second base station is a base station of a cell which causes interference.

14. The method according to claim 13, wherein the information indicating the determined downlink subframe is configured in the form of a bitmap.

15. The method according to claim 13, further comprising receiving, by the first base station, blank subframe setting information set by the second base station in consideration of the information indicating the determined downlink subframe.

16. The method according to claim 13, wherein the downlink subframe which cannot be used by the first base station is determined based on a downlink measurement result from a terminal served by the first base station.

17. The method according to claim 16, wherein the downlink subframe which cannot be used by the first base station is determined to be a subframe in which the strength of inter-cell interference from the second base station is higher than the strength of a signal from the first base station to the terminal served by the first base station by a predetermined threshold.

18. A base station of a cell which is subject to interference, which transmits information indicating resources, comprising:

a reception module configured to receive a signal from a base station of a cell which causes interference;

a transmission module configured to transmit a signal to the base station of the call which causes interference; and

a processor configured to control the base station of the cell which is subject to interference, which includes the reception module and the transmission module,

wherein the processor is configured to;

determine a downlink subframe which cannot be used by the base station of the cell which is subject to interference due to inter-cell interference among a plurality of downlink subframes; and

transmit information indicating the determined downlink subframe to the base station of the cell which causes interference through the transmission module.