Frequency reuse scheme for point to multipoint radio communication

• US 6,542,746 B1
• Filed: 10/04/1999
• Issued: 04/01/2003
• Est. Priority Date: 10/09/1998
• Status: Expired due to Term

• Current Assignee: RPX Clearinghouse LLC (RPX Corporation)
• Original Assignee: Nortel Networks Limited (Nortel Networks Corporation)
• Inventors: Dean, Stuart
• Primary Examiner(s): Vo, Nguyen T.
• Assistant Examiner(s): Orgad, Edan
• Application Number:
  US09/411,294
• Time in Patent Office: 1,275 Days
• Field of Search: 455/562, 455/446, 455/447, 455/422, 455/403, 455/561, 370/329, 370/330, 370/331, 370/332
• US Class Current: 455/447
• CPC Class Codes: H01Q 1/246 specially adapted for base stations
• CPC Class Codes: H01Q 3/2611 Means for null steering; Adaptive interference nulling
• 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

The invention provides frequency reuse techniques to enable fractional frequency reuse to be achieved for various cellular radio deployment grids, even for high order modulation such as 16 QAM and 64 QAM by the use of controlled and coordinated notched antenna patterns. The technique allows all frequencies to be used in all cells, thus maximizing system capacity while minimizing and controlling adjacent cell interference by the use of notched antenna patterns.

Claims

1. A method of reusing a set of frequencies throughout a celluar communication network including a plurality of base stations, comprising:

employing at at least two base stations a plurality of notched antenna patterns whose shapes are determined as an inverse function to transmission patterns of remote stations;

positioning each antenna pattern so that each of its notches is aimed at an adjoining base station;

allocating a different one of said set of frequencies to each antenna pattern of a base station; and

transmitting from a base station in a cell to a remote station in said cell on a frequency on which an extension of a path from the base station to the remote station into an adjoining cell passes through a notch of the antenna pattern allocated to the transmitting frequency in said adjoining cell.

2. The method according to claim 1 wherein:

the antenna patterns in any two adjoining cells are substantially the same except for relative angular orientation; and

the allocations of frequencies to antenna patterns in any two adjoining cells are entirely different.

3. The method according to claim 1 wherein:

each base station'"'"'s antenna patterns are positioned so that at least one notch is aimed at each adjoining base station.

4. The method according to claim 1 wherein:

adjoining cells use the same polarization.

5. The method according to claim 1 wherein:

adjoining cells use orthogonal polarizations.

6. The method according to claim 4 wherein:

a cell includes a repeater for transmitting into a portion of a cell; and

the base station and the repeater use orthogonal polarizations.

7. The method according to claim 1 wherein:

a base station has one or more additional antenna patterns with narrow beams aimed at base stations of adjoining cells, each transmitting backhaul data to an adjoining cell on a frequency whose antenna pattern has a notch along a path of backhaul transmission.

8. The method according to claim 7 wherein:

backhaul transmission and transmission to a remote station on the same frequency use orthogonal polarization.

9. A method of reusing a set of frequencies throughout a cellular communication network including a plurality of base stations, comprising:

employing at at least two base stations a plurality of antenna patterns each comprising a number N of lobes (where N is a positive integer greater than

     1) each lobe having a beamwidth substantially equal to 360/N degrees, the lobes being deployed 360/N degrees apart, one or more of the lobes having a notch whose shapes are determined as an inverse function to transmission patterns of remote stations;

positioning each antenna pattern so that each of its notches is aimed at an adjoining base station;

allocating a different one of said set of frequencies to each antenna pattern of each base station; and

transmitting from a base station to a remote station on a frequency on which an extension into an adjoining cell of a path from the base station to the remote station passes through a notch of the antenna pattern allocated to the transmitting frequency in the adjoining cell.

10. The method according to claim 9 wherein:

the antenna patterns in any two adjoining cells are substantially the same except for relative angular orientation; and

the allocations of frequencies to antenna patterns in any two adjoining cells are entirely different.

11. The method according to claim 9 wherein:

each base station'"'"'s antennas are positioned so that at least one notch is aimed at each adjoining base station.

12. The method according to claim 9 wherein:

N is equal to 4.

13. The method according to claim 12 wherein:

the antenna pattern allocated to a frequency in a cell is a mirror image of the antenna patterns allocated to the frequency in each adjoining cell.

14. A cellular communication network including a plurality of base stations, comprising:

at least two base stations having a plurality of notched antenna patterns;

each notch of each antenna pattern aimed at an adjoining base station and having shapes that are determined as an inverse function to transmission patterns of remote stations;

a different one of said set of frequencies allocated to each antenna pattern of a base station; and

wherein transmission from a base station in a cell to a remote station in said cell is on a frequency on which an extension of a path from the base station to the remote station into an adjoining cell passes through a notch of the antenna pattern allocated to the transmitting frequency in said adjoining cell.

15. The network according to claim 14 wherein:

the antenna patterns in any two adjoining cells are substantially the same except for relative angular orientation; and

the allocations of frequencies to antenna patterns in any two adjoining cells are entirely different.

16. The network according to claim 14 wherein:

each base station'"'"'s antenna patterns are positioned so that at least one notch is aimed at each adjoining base station.

17. The network according to claim 14 wherein:

adjoining cells use the same polarization.

18. The network according to claim 14 wherein:

adjoining cells use orthogonal polarizations.

19. The network according to claim 17 wherein:

a cell includes a repeater for transmitting into a portion of a cell; and

the base station and the repeater use orthogonal polarizations.

20. The network according to claim 14 wherein:

a base station has one or more additional antenna patterns with narrow beams aimed at base stations of adjoining cells, each transmitting backhaul data to an adjoining cell on a frequency whose antenna pattern has a notch along a path of backhaul transmission.

21. The network according to claim 20 wherein:

backhaul transmission and transmission to a remote station on the same frequency use orthogonal polarization.

22. A cellular communication network including a plurality of base stations, comprising:

at least two base stations having a plurality of antenna patterns each comprising a number N of lobes (where N is a positive integer greater than

     1) each lobe having a beamwidth substantially equal to 360/N degrees, the lobes being deployed 360/N degrees apart, one or more of the lobes having a notch whose shapes are determined as an inverse function to transmission patterns of remote stations;

each antenna pattern positioned so that each of its notches is aimed at an adjoining base station;

a different one of said set of frequencies allocated to each antenna pattern of a base station; and

wherein transmission from a base station in a cell to a remote station in said cell is on a frequency on which an extension into an adjoining cell of a path from the base station to the remote station passes through a notch of the antenna pattern allocated to the transmitting frequency in the adjoining cell.

23. The network according to claim 22 wherein:

the antenna patterns in any two adjoining cells are substantially the same except for relative angular orientation; and

the allocations of frequencies to antenna patterns in any two adjoining cells are entirely different.

24. The network according to claim 23 wherein:

each base station'"'"'s antennas are positioned so that at least one notch is aimed at each adjoining base station.

25. The network according to claim 23 wherein:

N is equal to 4.

26. The network according to claim 25 wherein:

the antenna pattern allocated to a frequency in a cell is a mirror image of the antenna patterns allocated to the frequency in each adjoining cell.