Method and apparatus for configuring PN-offsets for a non-uniform CDMA cellular network

• US 6,317,453 B1
• Filed: 04/07/2000
• Issued: 11/13/2001
• Est. Priority Date: 04/28/1997
• Status: Expired due to Term

• Current Assignee: Ericsson AB (Telefonaktiebolaget LM Ericsson)
• Original Assignee: Nortel Networks Limited (Nortel Networks Corporation)
• Inventors: Chang, Churui
• Primary Examiner(s): Bocure, Tesfaldet
• Application Number:
  US09/544,957
• Time in Patent Office: 585 Days
• Field of Search: 375/130, 375/140, 375/141, 455/446, 455/422, 455/522, 455/429, 455/438, 455/447, 455/448, 370/335, 370/342, 370/328
• US Class Current: 375/140
• CPC Class Codes: H04J 13/0022 PN, e.g. Kronecker
• CPC Class Codes: H04J 13/0074 Code shifting or hopping
• CPC Class Codes: H04J 13/16 Code allocation
• CPC Class Codes: H04W 16/02 Resource partitioning among network components, e.g. reuse partitioning
• CPC Class Codes: H04W 16/12 Fixed resource partitioning

Abstract

A method for configuring a spread spectrum cellular network for small-cell inclusion, by providing a finite series of PN-offsets, each PN-offset is separated by a constant value that is allotted to the spread spectrum cellular network. The finite series is portioned into a first and a second set. The second set subsequent to the first set and having sufficient PN-offset elements for a PN-offset reuse pattern having a plurality of cells, each cell having similar transmission characteristics. The second set is assigned to the PN-offset reuse pattern, deploying the cellular reuse pattern for a cellular network. Small cells are insertable into the spread spectrum cellular network by assigning the first set to a PN-offset reuse pattern having a plurality of small cells arranged in a small-cell reuse pattern, and deploying the small-cell reuse pattern. In another aspect, the method for configuring the spread spectrum cellular network involves sectoring each cell of the plurality of cells into a plurality of sectors. The sectored cells are assigned PN-offsets adjacent in the finite series together in each sector of the sectored cell while maintaining sufficient distance between cells that reuse an assigned PN-offset.

Claims

1. A method for configuring a spread spectrum cellular network, the method comprising the steps of:

providing a finite series of PN-offsets, each of the PN-offsets being separated by a value that is determined for the spread spectrum cellular network;

portioning the finite series of PN-offsets into a first and a second set, the second set subsequent to the first set and having sufficient PN-offset elements for a PN-offset reuse pattern having a plurality of cells;

assigning the first set to a first PN-offset reuse pattern, wherein the first PN-reuse pattern is employed for with a plurality of groups of a plurality of small cells; and

assigning the second set to a second PN-offset muse pattern, the second PN-offset reuse pattern coexistent with the first PN-offset reuse pattern, wherein the second PN-reuse pattern is employed for a plurality of groups of a plurality of large cells sharing a service coverage area with the plurality of groups of a plurality of small cells.

2. The method of claim 1 wherein:

the first PN-reuse pattern has a first spacing between PN-offsets;

the second PN-reuse pattern has a second spacing between PN-offsets; and

the second spacing is greater than the first spacing.

3. The method of claim 1 further comprising:

sectoring each small cell into a plurality of small cell sectors; and

assigning PN-offsets adjacent in the finite series to adjacent small cell sectors while maintaining sufficient distance between cells that reuse an assigned PN-offset.

4. The method of claim 1 further comprising:

sectoring each large cell into a plurality of large cell sectors; and

assigning PN-offsets adjacent in the finite series to adjacent large cell sectors while maintaining sufficient distance between cells that reuse an assigned PN-offset.

5. A spread spectrum cellular communication system comprising:

a first plurality of base stations, each servicing a small cell;

a second plurality of base stations, each servicing a large cell;

wherein each of the first plurality of base stations employs a PN-offset taken from a first PN-offset reuse pattern;

wherein each of the second plurality of base stations employs a PN-offset taken from a second PN-offset reuse pattern;

wherein the first PN-reuse pattern and the second PN-reuse pattern together form a finite series of PN-offsets, wherein the PN-offsets of the finite series of PN-offsets are separated by a value that is determined for the spread spectrum cellular network; and

wherein the plurality of groups of the plurality of large cells share a service coverage area with the plurality of groups of the plurality of small cells.

6. The spread spectrum cellular communication system of claim 5, wherein:

the first PN-reuse pattern has a first spacing between PN-offsets;

the second PN-reuse pattern has a second spacing between PN-offsets; and

the second spacing is greater than the first spacing.

7. The spread spectrum cellular communication system of claim 5, wherein:

some of the small cells are sectored into a plurality of small cell sectors; and

adjacent small cell sectors are assigned PN-offsets that are adjacent in the finite series while sufficient distance between cells that reuse an assigned PN-offset are maintained.

8. The spread spectrum cellular communication system of claim 5, wherein:

some of the large cells are sectored into a plurality of large cell sectors; and

adjacent large cell sectors are assigned PN-offsets that are adjacent in the finite series while sufficient distance between cells that reuse an assigned PN-offset are maintained.