DISTRIBUTED ALLOCATION OF PHYSICAL CELL IDENTIFIERS

• US 20110038326A1
• Filed: 03/01/2010
• Published: 02/17/2011
• Est. Priority Date: 08/13/2009
• Status: Active Grant

• Current Assignee: Alcatel-Lucent SA (Nokia Corporation)
• Original Assignee: Alcatel-Lucent SA (Nokia Corporation)
• Inventors: Pugeat, Jean-Michel, Deville, Frederic, DAVIES, RICHARD L., Kumar, Gopal N.
• Granted Patent: US 8,265,028 B2
• Time in Patent Office: Days
• US Class Current: 370/329
• CPC Class Codes: H04W 24/02 Arrangements for optimising operational condition
• CPC Class Codes: H04W 8/26 Network addressing or numbering for mobility support

Abstract

The present invention provides a method of assigning cell identifiers to a plurality of cells. The method includes detecting cells within a selected distance from a first cell in the plurality of cells. The distance is selected to encompass portions of neighbor cells of the first cell and neighbor-of-neighbor cells of the first cell. The method also includes assigning a first cell identifier to the first cell. The first cell identifier is different than cell identifiers assigned to the cells detected within the selected distance from the first cell.

Claims

1. A method of assigning cell identifiers to a plurality of cells, the method comprising:

detecting cells within a selected distance from a first cell in the plurality of cells, the distance being selected to encompass portions of neighbor cells of the first cell and neighbor-of-neighbor cells of the first cell; and

assigning a first cell identifier to the first cell, the first cell identifier being different than cell identifiers assigned to the cells detected within the selected distance from the first cell.

2. The method of claim 1, comprising selecting a distance from the first cell based on a maximum allowed path loss associated with the first cell.

3. The method of claim 2, wherein selecting the distance from the first cell comprises selecting a distance of at least twice the maximum allowed path loss associated with the first cell.

4. The method of claim 1, wherein detecting cells within the selected distance from the first cell comprises:

determining a plurality of physical locations of the plurality of cells;

determining a netting circle around the first cell using the selected distance; and

selecting at least one second cell when the physical location of said at least one second cell is within the netting circle.

5. The method of claim 1, wherein assigning the first cell identifier to the first cell comprises assigning a first cell identifier selected from a first subset of identifiers that have not been assigned to any of the cells detected within the selected distance from the first cell.

6. The method of claim 5, comprising determining that the first subset of identifiers have all been assigned to cells detected within the selected distance from the first cell, and wherein assigning the first cell identifier to the first cell comprises assigning a first cell identifier from a second subset of identifiers that are different from the first subset of identifiers and have been reserved for resolving collision and/or confusion between cell identifiers.

7. The method of claim 1, wherein a number of cell identifiers is less than the plurality of cells, and comprising assigning cell identifiers to each cell in the plurality of cells so that the cell identifier assigned to each cell does not collide with any cell identifier assigned to a cell within the selected distance from each cell and comprising assigning the cell identifiers to the plurality of cells so that the cell identifier assigned to each cell is not confused with any cell identifier assigned to a cell within the selected distance from each cell.

8. The method of claim 1, wherein each cell comprises a plurality of sectors and wherein assigning a first cell identifier to the first cell comprises assigning a plurality of first cell identifiers to the plurality of sectors in the first cell.

9. The method of claim 8, wherein assigning the plurality of first cell identifiers to the plurality of sectors in the first cell comprises:

defining a plurality of groups of cell identifiers so that each group of cell identifiers includes a number of mutually exclusive cell identifiers that is the same as the number of sectors in each cell; and

assigning a first group of cell identifiers to the first cell so that the first group of cell identifiers is different than any other group of cell identifiers assigned to cells within the selected distance; and

assigning cell identifiers from the first group of cell identifiers to each sector of the first cell.

10. A method of assigning cell identifiers to a plurality of cells, the method comprising:

selecting a cell from the plurality of cells;

detecting cells within a selected distance from the selected cell, the distance being selected to encompass portions of neighbor cells of the selected cell and neighbor-of-neighbor cells of the selected cell;

assigning a cell identifier to the selected cell, the cell identifier being different than cell identifiers assigned to the cells detected within the selected distance from the selected cell; and

iteratively selecting other cells from the plurality of cells, detecting cells within the selected distance from the other selected cells, and assigning cell identifiers to each other selected cell so that the assigned cell identifiers are different than cell identifiers assigned to the cells within the selected distance from each other selected cell.

11. The method of claim 10, comprising selecting the distances from the selected cells based on a maximum allowed path loss associated with the selected cells.

12. The method of claim 11, wherein selecting the distances from the cells comprises selecting a distance of at least twice the maximum allowed path loss associated with the selected cells.

13. The method of claim 10, wherein detecting cells within the selected distance from the selected cells comprises:

determining a plurality of physical locations of the plurality of cells;

determining a netting circle around the each cell using the selected distance; and

selecting at least one cell when the physical location of said at least one cell is within the netting circle.

14. The method of claim 10, wherein assigning the cell identifiers to the cells comprises assigning cell identifiers selected from a first subset of identifiers.

15. The method of claim 14, comprising determining that the first subset of identifiers have all been assigned to cells detected within the selected distance from the selected cell, and wherein assigning the cell identifier to the selected cell comprises assigning a first cell identifier from a second subset of identifiers that are different from the first subset of identifiers and have been reserved for resolving collision and/or confusion between cell identifiers.

16. The method of claim 10, wherein a number of cell identifiers is less than a number of cells, and comprising assigning cell identifiers to each cell in the plurality of cells so that the cell identifier assigned to each cell does not collide with any cell identifier assigned to a cell within the selected distance from each cell and comprising assigning the cell identifiers to the plurality of cells so that the cell identifier assigned to each cell is not confused with any cell identifier assigned to a cell within the selected distance from each cell.

17. The method of claim 10, wherein each cell comprises a plurality of sectors and wherein assigning a cell identifier to the selected cell comprises assigning a plurality of cell identifiers to the plurality of sectors in the selected cell.

18. The method of claim 17, wherein assigning the plurality of cell identifiers to the plurality of sectors in the selected cell comprises:

defining a plurality of groups of cell identifiers so that each group of cell identifiers includes a number of mutually exclusive cell identifiers that is the same as the number of sectors in each cell; and

assigning a group of cell identifiers to the selected cell so that the group of cell identifiers is different than any other group of cell identifiers assigned to cells within the selected distance; and

assigning cell identifiers from the group of cell identifiers to each sector of the selected cell.