Queue based power control scheduling

• US 6,374,117 B1
• Filed: 12/22/1999
• Issued: 04/16/2002
• Est. Priority Date: 12/22/1999
• Status: Expired due to Term

• Current Assignee: Telefonaktiebolaget LM Ericsson
• Original Assignee: Telefonaktiebolaget LM Ericsson
• Inventors: Denkert, Niklas, Lundborg, Tomas
• Primary Examiner(s): LE, THANH C
• Application Number:
  US09/468,882
• Time in Patent Office: 846 Days
• Field of Search: 455/517, 455/522, 455/69, 455/70, 455/73, 455/422, 455/450, 455/455, 370/327, 370/330, 370/331, 370/332, 370/341
• US Class Current: 455/522
• CPC Class Codes: H04L 1/0001 Systems modifying transmission characteristics according to link quality, e.g. power backoff adaptive data allocation for multicarrier modulation H04L5/0044; controlling transmission power for radio systems H04W52/04
• CPC Class Codes: H04L 1/0003 by switching between different modulation schemes
• CPC Class Codes: H04L 1/0009 by adapting the channel coding H04L1/1812 takes precedence
• CPC Class Codes: H04L 1/0017 where the mode-switching is based on Quality of Service requirement
• CPC Class Codes: H04L 1/0018 based on latency requirement
• CPC Class Codes: H04W 52/265 taking into account the quality of service QoS
• CPC Class Codes: H04W 52/267 taking into account the information rate
• CPC Class Codes: H04W 52/281 taking into account user or data type priority
• CPC Class Codes: H04W 52/286 during data packet transmission, e.g. high speed packet access [HSPA]
• CPC Class Codes: H04W 52/36 with a discrete range or set of values, e.g. step size, ramping or offsets
• CPC Class Codes: H04W 72/0473 the resource being transmission power
• CPC Class Codes: H04W 72/1221 based on age of data to be sent

Abstract

A method and system for controlling a transmit power level based upon queue delay for packets in a wireless packet data system is described. Packet data throughput can be improved for selected links based upon queue delay, e.g., those data packets which have experienced a lengthy queue delay can be provided with a higher quality link by increasing their transmit power. The determination of whether or not to prioritize data packets through increased transmit power can be made based upon, for example, a subscriber'"'"'s QoS profile.

Claims

1. A wireless packet data system comprising:

a buffer for storing a data packet to be transmitted;

a processor for monitoring a length of time during which said data packet has been stored in said buffer and selectively adjusting a transmit power based on said length of time;

a transceiver for transmitting said data packet at said adjusted transmit power.

2. The system of claim 1, wherein said processor initially determines said transmit power based upon a power control algorithm using measurement data associated with a radio link over which said data packet is to be transmitted.

3. The system of claim 2, wherein said processor compares said length of time with a threshold time and selects one of said initially determined transmit power and an increased transmit power based on a result of said comparison.

4. The system of claim 2, wherein said threshold time is determined based upon a user'"'"'s subscription profile.

5. The system of claim 1, wherein said processor compares said length of time with a threshold time and selects one of an initial transmit power and an increased transmit power based on a result of said comparison.

6. The system of claim 5, wherein said threshold time is determined based upon a user'"'"'s subscription profile.

7. The system of claim 1, wherein said processor also adjusts a modulation used to process said data packet based upon said adjusted transmit power.

8. The system of claim 1, wherein said processor also adjusts an error correction coding used to process said data packet based upon said adjusted transmit power.

9. The system of claim 1, wherein said buffer is disposed in a switch.

10. The system of claim 1, wherein said processor adjusts said transmit power for every burst.

11. The system of claim 1, wherein said buffer is disposed in a base station.

12. A method for controlling transmit power in a wireless packet data communication system comprising the steps of:

determining a transmission delay associated with communication of a data packet between a remote station and said system; and

selectively adjusting a transmit power associated with transmitting said data packet based on said determined delay.

13. The method of claim 12, further comprising the steps of:

identifying a delay threshold associated with a particular connection between a remote station and said system;

comparing said determined transmission delay with said delay threshold; and

increasing said transmit power if said determined delay exceeds said delay threshold.

14. The method of claim 13, wherein said step of identifying further comprises the step of:

retrieving a delay parameter from a user'"'"'s subscription profile; and

calculating said delay threshold based on said delay parameter.

15. The method of claim 12, further comprising the step of:

selecting a modulation scheme based on said adjusted transmit power.

16. The method of claim 12 further comprising the step of:

selecting an error correction coding level based on said adjusted transmit power.

17. The method of claim 12, wherein said step of selectively adjusting occurs for every transmit burst.

18. A system for controlling throughput in a packet radiocommunication system comprising:

means for evaluating a delay-based parameter associated with transmitting a data packet;

means for selectively increasing a transmit power responsive to an output of said means for evaluating; and

means for changing at least one of a modulation and an error correction coding scheme when said transmit power is increased.

19. The system of claim 18, wherein said means for changing at least one of a modulation and an error correction coding scheme changes a type of modulation used to process said data packet to a higher level modulation.

20. The system of claim 18, wherein said means for changing at least one of a modulation and an error correction coding scheme changes a type of error correction coding scheme used to process said data packet to a type of error correction coding employing less redundancy.

21. The system of claim 18, wherein said means for evaluating a delay-based parameter compares a queue delay associated with said data packet to a delay threshold.

22. The system of claim 18, wherein said means for evaluating a delay-based parameter takes into account a number of packets to be transmitted.

23. The system of claim 18, wherein said means for evaluating a delay-based parameter takes into account a delay class associated with a quality-of-service profile.