Methods and apparatus for controlling a base stations's transmission power

• US 20070253385A1
• Filed: 10/13/2006
• Published: 11/01/2007
• Est. Priority Date: 10/14/2005
• Status: Active Grant

• Current Assignee: Qualcomm, Inc.
• Original Assignee: Qualcomm, Inc.
• Inventors: Das, Arnab, Li, Junyi, Wu, Xinzhou
• Granted Patent: US 8,694,042 B2
• Time in Patent Office: Days
• US Class Current: 370/338
• CPC Class Codes: H04B 17/24 with feedback of measurements to the transmitter
• CPC Class Codes: H04B 17/382 for resource allocation, admission control or handover
• CPC Class Codes: H04W 16/06 Hybrid resource partitioning, e.g. channel borrowing
• CPC Class Codes: H04W 16/08 Load shedding arrangements
• CPC Class Codes: H04W 24/10 Scheduling measurement reports ; Arrangements for measurement reports
• CPC Class Codes: H04W 36/20 for optimising the interference level
• CPC Class Codes: H04W 4/06 Selective distribution of broadcast services, e.g. multimedia broadcast multicast service [MBMS]; Services to user groups; One-way selective calling services
• CPC Class Codes: H04W 52/143 Downlink power control
• CPC Class Codes: H04W 52/343 taking into account loading or congestion level
• CPC Class Codes: H04W 52/40 during macro-diversity or soft handoff
• CPC Class Codes: H04W 72/541 using the level of interference

Abstract

A base station receives loading information indicative of the loading of other base stations and determines a downlink transmission power budget as a function of the received loading factor information. The base station may decrease/increase a current power budget dedicated to downlink traffic channel segments in response to detecting an increase/decrease in loading at an adjacent base station. Thus, base stations operate in a cooperative manner reducing power output, in at least some cases, where loading at a neighboring base station increases thereby reducing the interference to the base station with the increased load. A base station can consider possible alternative transmission power levels, estimated levels of interference, and/or possible alternative data rates in making trade-off decisions regarding downlink power budget.

Claims

1. A method of operating a first base station in a multiple access wireless communications system including a plurality of base stations, each of said plurality of base stations including at least one base station attachment point, the method comprising:

receiving second base station loading factor information indicative of loading of a second base station attachment point corresponding to a second base station; and

determining a downlink transmission power budget as a function of said received second base station loading factor information.

2. The method of claim 1, wherein determining a downlink transmission power budget is further performed as a function of additional loading factor information corresponding to another base station attachment point.

3. The method of claim 2,

wherein said another base station attachment point corresponds to said first base station, and

wherein said determining a downlink transmission power budget includes comparing said additional loading factor information to said second base station loading factor information.

4. The method of claim 2, wherein said determined downlink transmission power budget is a power budget for a set of downlink communications channels including at least a pilot channel and a data traffic channel;

and

wherein a portion of said determined downlink transmission power budget for the pilot channel is independent of said additional and second loading factor information and wherein a portion of the determined downlink transmission power budget corresponding to said data traffic channel depends on the second base loading factor information and said additional loading factor information.

5. The method of claim 3, wherein determining said power budget includes:

determining said power budget to correspond to a first value indicative of said budget when said comparing indicates said second base station loading is greater than said first base station loading; and

determining said power budge to correspond to a second value indicative of a power budget greater than the power budget indicated by said first value when said comparing indicates said second base station loading is less than said first base station loading.

6. The method of claim 2, wherein determining said power budget includes:

decreasing a current power budget in response to detecting an increase in loading at said second base station.

7. The method of claim 2, wherein determining said power budget includes:

increasing a current power budget in response to detecting an decrease in loading at said second base station.

8. The method of claim 2, wherein determining said power budget includes:

increasing a current power budget in response to detecting an increase in loading at said first base station.

9. The method of claim 2, wherein determining said power budget includes:

decreasing a current power budget in response to detecting an decrease in loading at said first base station.

10. A base station comprising:

means for receiving base station loading factor information indicative of loading of a base station attachment point corresponding to another base station; and

means for determining a downlink transmission power budget, wherein said means for determining a downlink transmission power budget determines the downlink transmission power budget as a function of said received base station loading factor information.

11. The base station of claim 10, wherein said means for determining a downlink transmission power budget determines said downlink transmission power budget as a function of additional loading factor information corresponding to an additional base station attachment point.

12. The base station of claim 11,

wherein said additional base station attachment point corresponds to said base station, and

wherein said means for determining a downlink transmission power budget includes means for comparing said additional loading factor information to said other base station loading factor information.

13. The base station of claim 11, wherein said determined downlink transmission power budget is a power budget for a set of downlink communications channels including at least a pilot channel and a data traffic channel;

and

wherein a portion of said determined power budget for the pilot channel is independent of said other and additional loading factor information and wherein a portion of the determined downlink transmission power budget corresponding to said data traffic channel depends on the other base loading factor information and said additional loading factor information.

14. The base station of claim 12, wherein said means for determining a downlink transmission power budget determines said downlink transmission power budget to correspond to a first value indicative of said budget when said comparing indicates said other base station loading is greater than said base station loading;

and determines said downlink transmission power budge to correspond to a second value indicative of a power budget greater than the power budget indicated by said first value when said comparing indicates said other base station loading is less than said base station loading.

15. The base station of claim 11, wherein said means for determining a downlink transmission power budget decreases a current power budget in response to detecting an increase in loading at said other base station.

16. The base station of claim 11, wherein said means for determining a downlink transmission power budget increases a current power budget in response to detecting a decrease in loading at said second base station.

17. The base station of claim 11, wherein said means for determining a downlink transmission power budget includes means for tracking loading changes at said base station, and wherein said means for determining downlink transmission power budget increases a current power budget in response to detecting an increase in loading at said base station.

18. The base station of claim 11, wherein said means for determining a downlink transmission power budget includes means for tracking loading changes at said base station, and wherein said means for determining for a downlink transmission power budget decreases a current power budget in response to detecting an decrease in loading at said base station.

19. A base station comprising:

an interface for receiving signals communicating base station loading factor information indicative of loading of at least one base station attachment point corresponding to at least one other base station;

a loading factor information recovery module for recovering loading factor information corresponding to at least one other base station from said received signals;

a downlink transmission power budget determination module, wherein said downlink transmission power budget determination module determines a downlink transmission power budget for an attachment point of the base station as a function said recovered loading factor information corresponding to at least one other base station.

20. The base station of claim 19, further comprising:

a loading factor determination module for determining a loading factor corresponding to an attachment point of the base station;

a loading factor comparison module for comparing the determined loading factor corresponding to an attachment point of the base station to a recovered loading factor corresponding to an attachment point of another base station, and wherein said downlink transmission power budget determination module uses results of the loading factor comparison module in determining the downlink power budget.

21. The base station of claim 19, wherein said determined power budget is a power budget for a set of downlink communications channels including at least a pilot channel and a data traffic channel;

and

wherein a portion of said determined power budget for the pilot channel is independent of said other and additional loading factor information and wherein a portion of the power budget corresponding to said data traffic channel depends on the other base loading factor information and said additional loading factor information.

22. The base station of claim 21, wherein said downlink transmission power budget determination module determines said power budget to correspond to a first value indicative of said budget when said loading factor comparison module determines said other base station loading is greater than said base station loading;

and determines said power budget to correspond to a second value indicative of a power budget greater than the power budget indicated by said first value when said loading factor comparison module indicates said other base station loading is less than said base station loading.

23. The base station of claim 21, further comprising:

a loading factor tracking module for tracking changes in loading factors at base station attachment points, and wherein said downlink transmission power budget determination module decreases a current power budget in response to detecting an increase in loading at one of said other base stations.

24. The base station of claim 21, further comprising:

a loading factor tracking module for tracking changes in loading factors at base station attachment points, and wherein said downlink transmission power budget determination module increases a current power budget in response to detecting a decrease in loading at one of said other base stations.

25. The base station of claim 21, further comprising:

a loading factor tracking module for tracking changes in loading factors at base station attachment points and, wherein said downlink transmission power budget determination module increases current power budget in response to detecting an increase in loading at an attachment point of said base station.

26. The base station of claim 21, further comprising:

a loading factor tracking module for tracking changes in loading factors at base station attachment points, and wherein said downlink transmission power budget determination module decreases a current power budget in response to detecting a decrease in loading at an attachment point of said base station.

27. A computer readable medium embodying machine executable instructions for controlling a first base station in a multiple access wireless communications system including a plurality of base stations to implement a method, the method comprising:

receiving second base station loading factor information indicative of loading of a second base station attachment point corresponding to a second base station; and

determining a downlink transmission power budget as a function of said received second base station loading factor information.

28. The computer readable medium of claim 27, further embodying machine executable instructions for determining the downlink transmission power budget as a function of additional loading factor information corresponding to another base station attachment point.

29. The computer readable medium of claim 28, wherein said another base station attachment point corresponds to said first base station.

30. The computer readable of claim 29 further embodying machine executable instructions for:

comparing additional loading factor information to said second base station loading factor information as part of determining the downlink transmission power budget.

31. The computer readable medium of claim 30, wherein said determined downlink transmission power budget is a power budget for a set of downlink communications channels including at least a pilot channel and a data traffic channel;

and

wherein a portion of said determined downlink transmission power budget for the pilot channel is independent of said additional and second loading factor information and wherein a portion of the determined downlink transmission power budget corresponding to said data traffic channel depends on the second base loading factor information and said additional loading factor information.

32. A base station operable in a communication system, the base station comprising:

a processor configured to;

receive second base station loading factor information indicative of loading of a second base station attachment point corresponding to a second base station; and

determine a downlink transmission power budget as a function of said received second base station loading factor information.

33. The base station of claim 32, wherein the processor is further configured to:

determine the downlink transmission power budget as a function of additional loading factor information corresponding to another base station attachment point.

34. The base station of claim 33,

wherein said another base station attachment point corresponds to said first base station, and

wherein the processor is further configured to determine the downlink transmission power budget by operations including comparing additional loading factor information to said second base station loading factor information.

35. The base station of claim 34, wherein said determined downlink transmission power budget is a power budget for a set of downlink communications channels including at least a pilot channel and a data traffic channel;

and

wherein a portion of said determined downlink transmission power budget for the pilot channel is independent of said additional and second loading factor information and wherein a portion of the determined downlink transmission power budget corresponding to said data traffic channel depends on the second base loading factor information and said additional loading factor information.