INTER-CELL INTERFERENCE COORDINATION METHOD AND APPARATUS FOR WIRELESS COMMUNICATION SYSTEM

• US 20100267408A1
• Filed: 04/20/2010
• Published: 10/21/2010
• Est. Priority Date: 04/20/2009
• Status: Active Grant

• Current Assignee: Samsung Electronics Co. Ltd.
• Original Assignee: Samsung Electronics Co. Ltd.
• Inventors: Kim, Jong In, Lee, Neung Hyung, Kwon, Sung Oh, Lee, Kyung Chun, Youm, Ho Sun
• Granted Patent: US 8,412,256 B2
• Time in Patent Office: Days
• US Class Current: 455/509
• CPC Class Codes: H04W 52/243 taking into account interferences
• CPC Class Codes: H04W 72/27 between access points
• CPC Class Codes: H04W 72/541 using the level of interference

Abstract

An inter-cell interference coordination method and apparatus is provided for mitigating inter-cell interference in a wireless communication system by using interference coordination information exchanged among neighbor base stations. The method includes receiving, at a serving base station, power control messages transmitted by neighbor base stations, receiving incoming interference coordination messages transmitted by neighbor base stations, each message including interference indicators of resource blocks, allocating the resource blocks with transmission power per resource block to user equipments served by the base station based on the power control and interference coordination messages, generating outgoing interference coordination messages for the respective neighbor base stations based on the resource block allocation result, and transmitting the interference coordination messages to the neighbor base stations, respectively.

Claims

1. An inter-cell interference mitigation method for a wireless communication system, comprising:

receiving, at a serving base station, power control messages transmitted by neighbor base stations;

receiving, by the serving base station, incoming interference coordination messages transmitted by neighbor base stations, each coordination message including interference indicators of resource blocks;

allocating, by the serving base station, the resource blocks with transmission power per resource block to user equipments served by the serving base station based on the power control messages and interference coordination messages;

generating, by the serving base station, outgoing interference coordination messages for the respective neighbor base stations based on the resource block allocation result; and

transmitting, by the serving base station, the interference coordination messages to the neighbor base stations, respectively.

2. The Inter-cell interference mitigation method of claim 1, wherein generating outgoing interference coordination messages comprises:

setting, if each resource block is used, the interference indicator of the resource block to a use state and to a non-use state if each resource block is not used;

comparing a received signal strength of each neighbor base station on each resource block in use state with a threshold; and

resetting, if the received signal strength is greater than or equal to the threshold, the interference indicator to interference state, and to a use state if the received signal strength is less than a threshold.

3. The inter-cell interference mitigation method of claim 2, wherein allocating the resource blocks includes excluding the allocation of the resource blocks of which interference indicators are set to a non-use state.

4. The inter-cell interference mitigation method of claim 2, wherein allocating the resource blocks includes assigning the resource blocks dedicated to the serving base station for the user equipments located anywhere in a cell, allocating the resource blocks dedicated to the neighbor base stations for the user equipments located the a center of the cell, and allocating the resource blocks of which interference indicators are set to interference state for no user equipment.

5. The inter-cell interference mitigation method of claim 2, wherein the power control message is transmitted at a first time interval, and the interference coordination message is transmitted at a second time interval which is shorter than the first time interval.

6. The inter-cell interference mitigation method of claim 5, wherein the interference coordination message is generated per neighbor base station.

7. An inter-cell interference mitigation apparatus for a wireless communication system, comprising:

a message processor which receives incoming power control messages and interference coordination messages transmitted by neighbor base stations and transmits outgoing interference coordination messages to the neighbor base stations;

an interference processor which extracts interference indicators from the incoming interference coordination messages; and

a scheduler which allocates resource blocks to user equipments in a cell with transmission power per resource block based on the interference indicators and generates the outgoing interference coordination messages.

8. The inter-cell interference mitigation apparatus of claim 7, wherein the scheduler sets, if each resource block is used, the interference indicator of the resource block to a use state and to a non-use state if each resource block is not used, compares a received signal strength of each neighbor base station on each resource block in the use state with a threshold, and resets, if the received signal strength is greater than or equal to the threshold, the interference indicator to interference state, and to a use state if the received signal strength is less than the threshold.

9. The inter-cell interference mitigation apparatus of claim 8, wherein the scheduler excludes the allocation of the resource blocks of which interference indicators are set to a non-use state.

10. The inter-cell interference mitigation apparatus of claim 8, wherein the scheduler assigns the resource blocks dedicated to the serving base station for the user equipments located anywhere in a cell, assigns the resource blocks dedicated to the neighbor base stations for the user equipments located the a center of the cell, and assigns the resource blocks of which interference indicators are set to interference state for no user equipment.

11. The inter-cell interference mitigation apparatus of claim 8, wherein the power control message is transmitted at a first time interval, and the interference coordination message is transmitted at a second time interval, which is shorter than the first time interval.

12. The inter-cell interference mitigation apparatus of claim 11, wherein the interference coordination message is generated per neighbor base station.