Methods and Apparatus for Inter-cell Interference Coordination Self-Organized Network

• US 20120120893A1
• Filed: 11/17/2011
• Published: 05/17/2012
• Est. Priority Date: 11/17/2010
• Status: Active Grant

• Current Assignee: Honor Device Company Limited
• Original Assignee: Futurewei Technologies Incorporated (Huawei Investment & Holding Co., Ltd.)
• Inventors: Baligh, Mohammadhadi, Qian, Ying
• Granted Patent: US 8,817,723 B2
• Time in Patent Office: Days
• US Class Current: 370/329
• CPC Class Codes: H04W 16/10 Dynamic resource partitioning
• CPC Class Codes: H04W 24/02 Arrangements for optimising operational condition
• CPC Class Codes: H04W 24/08 Testing, supervising or monitoring using real traffic

Abstract

A method of resource allocation for use in a wireless network is disclosed. A network coloring decision to assign a plurality of resource blocks to a plurality of cells within the wireless network is triggered upon occurrence of a network event. A network coloring is performed by assigning each cell of the plurality of cells a resource block from the plurality of resource blocks. An effect of interference among adjacent cells with a same resource block assignment is reduced as measured by a network performance metric related to a number of resource block assignment conflicts over the plurality of cells.

Claims

1. A method of resource allocation for use in a wireless network, the method comprising:

triggering, upon occurrence of a network event, a network coloring decision to assign a plurality of resource blocks to a plurality of cells within the wireless network; and

performing a network coloring by assigning each cell of the plurality of cells a resource block from the plurality of resource blocks, wherein an effect of interference among adjacent cells with a same resource block assignment is reduced as measured by a network performance metric related to a number of resource block assignment conflicts over the plurality of cells.

2. The method of claim 1, further comprising:

informing a plurality of base stations, each base station located in an associated cell of the plurality of cells; and

configuring each base station of the plurality of base stations to operate with the resource block assigned to the associated cell.

3. The method of claim 1, wherein a resource block comprises a frequency bandwidth, a time slot, or a power level of a signal.

4. The method of claim 1, wherein the network event comprises a cell addition, a cell deletion, a network change, a frequency band change, a periodic trigger, or a change in the network performance metric.

5. The method of claim 1, wherein performing the network coloring comprises:

selecting a first cell among the plurality of cells and assigning a first resource block to the first cell;

determining which cell among the plurality of cells that have not been assigned a resource block is a first most sensitive cell, the first most sensitive cell being most sensitive to interference caused by the first resource block assigned to the first cell; and

assigning a most favorite resource block to the first most sensitive cell;

wherein the first most sensitive cell and the most favorite resource block are determined by measurement of the network performance metric.

6. The method of claim 5, wherein performing the network coloring further comprising:

determining which cell that has not been assigned a resource block is a most sensitive cell remaining, the most sensitive cell remaining being most sensitive to interference caused by previously assigned resource blocks;

assigning a next most favorite resource block to the most sensitive cell remaining, wherein the most sensitive cell remaining and the next most favorite resource block are determined by measurement of the network performance metric; and

repeating the determining and assigning steps until each of the plurality of cells has been assigned a resource block.

7. The method of claim 1, further comprising:

assigning each cell among the plurality of cells another resource block, wherein the resource block of the cell is assigned to a first area of the cell and the another resource block is assigned to a second area of the cell, wherein an effect of interference among adjacent cells with a same resource block assignment is reduced measured by the network performance metric related to a number of resource block assignment conflicts over the plurality of cells.

8. The method of claim 1, wherein the network performance metric comprises a measurement of cell loading, cell edge loading, cell sizes, number of users, handover success rate, or user equipment (UE) signal to interference and noise ratio (SINR).

9. The method of claim 1, wherein the network performance metric is based on a network neighboring relation table (NRT) maintained for the network, and the network NRT comprises a matrix of size of n*n, wherein n is a number of the plurality of cells,

wherein an element B_ij of the matrix is B_ij=A_ij+A_ji,

wherein

10. The method of claim 9, wherein the A_ij^k is a relative measurement of a reference signal receive power (RSRP) caused by the assigned resource block of the cell j measured by an UE in the cell i, and A_ji^k is a measurement of a RSRP caused by the assigned resource block of the cell i measured by an UE in a cell j.

11. The method of claim 10, wherein a base station located in the cell i receives the data A_ij^k measured by an UE in the cell i, and maintains data A_ij^k in the base station.

12. The method of claim 11, wherein the base station located in the cell i further maintains a base station NRT generated from a plurality of data A_ij^k received from a plurality of UEs located in the cell i.

13. The method of claim 12, wherein the base station located in the cell i further reports the base station NRT to a network management system which generates the network NRT for the network.

14. The method of claim 13, wherein the network management system determines when to trigger the coloring decision based on the generated network NRT for the network and a predetermined threshold for the network NRT.

15. A method of resource allocation for use in a wireless network, the method comprising:

selecting a first cell among a plurality of cells and assigning a first resource block to the first cell;

determining which cell among the plurality of cells that have not been assigned a resource block is a first most sensitive cell, the first most sensitive cell being most sensitive to interference caused by the first resource block assigned to the first cell;

assigning a most favorite resource block to the first most sensitive cell, wherein the first most sensitive cell and the most favorite resource block are determined by measurement of a network performance metric;

determining a most sensitive cell remaining from cells that have not been assigned a resource block, the most sensitive cell remaining being most sensitive to interference caused by previously assigned resource blocks;

assigning a next most favorite resource block to the most sensitive cell remaining, wherein the most sensitive cell remaining and the next most favorite resource block are determined by measurement of the network performance metric; and

repeating the steps of determining a most sensitive cell remaining and assigning a next most favorite resource block until each of the plurality of cells has been assigned a resource block .

16. The method of claim 15, further comprising:

informing a plurality of base stations, each base station located in an associated cell of the plurality of cells; and

configuring each base station to operate with the resource block assigned to the associated cell.

17. The method of claim 15, wherein a resource block comprises a frequency bandwidth, a time slot, or a power level of a signal.

18. The method of claim 15, wherein the network event comprises a cell addition, a cell deletion, a network change, a frequency band change, a periodic trigger, or a change in the network performance metric.

19. The method of claim 15, wherein an effect of interference among adjacent cells with a same resource block assignment is reduced as measured by a network performance metric related to a number of resource block assignment conflicts over the plurality of cells.

20. The method of claim 15, wherein the network performance metric comprises a measurement of cell loading, cell edge loading, cell sizes, number of users, handover success rate, or user equipment (UE) signal to interference and noise ratio (SINR).

21. The method of claim 15, wherein the network performance metric is based on a network neighboring relation table (NRT) maintained for the network, and the network NRT comprises a matrix of size of n*n, wherein n is a number of the plurality of cells,

wherein an element B_ij of the matrix is B_ij=A_ij+A_ji,

wherein

22. An apparatus to manage resource allocation in a wireless network, the apparatus comprising:

a decision unit configured to receive notice of a network event and cause triggering of a coloring decision to assign a plurality of resource blocks to a plurality of cells within the network based on the network event; and

an assignment unit configured to receive a network performance metric and perform a network coloring by assigning each cell among the plurality of cells an associated resource block, wherein an effect of interference among adjacent cells with a same resource block assignment is reduced measured by the network performance metric related to a number of resource block assignment conflicts over the plurality of cells.

23. The apparatus of claim 22, further comprising:

a storage unit configured to store a network neighboring relation table (NRT) maintained for the network, and the network NRT comprising a matrix of size of n*n, wherein n is a number of cells,

wherein an element B_ij of the matrix is B_ij=A_ij+A_ij,

wherein

24. The apparatus of claim 23, wherein the A_ij^k is a relative measurement of a reference signal receive power (RSRP) caused by the assigned resource block of the cell j measured by an UE in the cell i, and A_ji^k is a measurement of a RSRP caused by the assigned resource block of the cell i measured by an UE in a cell j.

25. The apparatus of claim 24, wherein the network NRT for the network is generated from a plurality of base station NRTs received from a plurality of base stations located in the plurality of cells, and a base station NRT for the base station located in the cell i is generated from a plurality of data A_ij^k received from a plurality of UEs located in the cell i.

26. An apparatus located in a cell of a wireless network, comprising:

a collection unit configured to receive a plurality of data A_ij^k measured by a plurality of User Equipments (UE) in the cell, wherein an A_ij^k is a relative measurement of a reference signal receive power (RSRP) caused by an assigned resource block of an adjacent cell j measured by an UE in the cell, wherein the assigned resource block comprises a frequency bandwidth, a time slot, or a power level of a signal;

a storage unit configured to store a base station neighboring relation table (NRT) generated from the plurality of data A_ij^k; and

a reporting unit configured to report the base station NRT to a network management system.

27. The apparatus of claim 26, wherein the base station NRT comprises:

a matrix of size of s*s, wherein s is a number of adjacent cells around the cell the apparatus is located,

wherein an element B_ij of the matrix is B_ij=A_ij+A_ji,

where

28. The apparatus of claim 26, further comprising:

a receiver configured to receive an assigned resource block; and

a mode configuration unit configured to perform a configuration of the assigned resource block so that a UE can communicate with the apparatus using the assigned resource block.