Adapting transmission parameters in a transmitting node of a data communication system to the current link quality of a data communication channel

• US 7,512,097 B2
• Filed: 12/01/2004
• Issued: 03/31/2009
• Est. Priority Date: 12/05/2003
• Status: Expired due to Fees

• Current Assignee: International Business Machines Corporation
• Original Assignee: International Business Machines Corporation
• Inventors: Jelitto, Jens, Truong, Hong Linh
• Primary Examiner(s): Duong; Frank
• Application Number:
  US11/000,842
• Publication Number:
  US 20050128998A1
• Time in Patent Office: 1,581 Days
• Field of Search: None
• US Class Current: 370/329
• 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 1/1867 Arrangements specially adapted for the transmitter end

Abstract

Provides apparatus, systems and methods for adapting a first and second transmission parameter R, P in a transmitting node of a data communication system to the current link quality of a data communication channel. A method comprises in the transmitting node counting the number of successful transmissions s, each successful transmission bases on a receipt of an acknowledgment “ACK”, and comparing the number of successful transmissions s against a threshold value S_max. In the event of reaching the threshold value S_max and operating with the first and second transmission parameter R, P in a predetermined parameter space, the method further comprises adapting at least one of the first and second transmission parameters R, P in dependence on a critical value that due to the current link quality corresponds to a temporarily unsupported value of one of the first and second transmission parameters R, P.

Claims

1. A method for adapting first and second transmission parameters in a transmitting node of a data communication system to the current link quality of a data communication channel, the method comprising in the transmitting node the steps of:

counting the number of successful transmissions, each successful transmission bases on a receipt of an acknowledgement;

comparing the number of successful transmission against a threshold value; and

in the event of achieving the number of successful transmissions with the threshold value and operating with the first and second transmission parameters in a predetermined parameter space,

jointly adapting both of the first and second transmission parameters in dependence on a critical value that due to the current link quality corresponds to a temporarily unsupported rate and power value of one of the first and second transmission parameters, wherein said jointly adapting includes one of;

supporting a highest possible data rate by increasing a data rate transmission until a maximum rate is found, and if said rate cannot be increased further, reducing said transmit power level;

or, supporting a lowest possible transmit power level by decreasing a power transmission level until a power level can not be further reduced and to increase the transmit rate when the transmit power level can not be further decreased.

2. A method according to claim 1, wherein the step of adapting further comprises adapting the at least one of the first and second transmission parameters in dependence on a delay value.

3. A method according to claim 2, wherein in the event of equating the delay value to a maximum transmission value, the critical value is adjusted.

4. A method according to claim 2, wherein in the event of equating the delay value to a maximum success transmission value, the critical value is set to nil.

5. A method according to claim 1, further comprising operating in one of a throughput performance mode and a power saving mode.

6. A method according to claim 5, wherein each of the first and second transmission parameters is associated with a data rate and a power level in dependence of the mode.

7. A program storage device readable by computer, tangibly embodying a program of instructions executable by the computer to perform method steps for adapting first and second transmission parameters in a transmitting node of data communication system to the current link quality of a data communication channel, said method steps comprising the steps of claim 5.

8. A computer program product comprising a computer usable medium having computer readable program code means embodied therein for execution by a processor to perform method steps for adapting first and second transmission parameters in a transmitting node of a data communication system to a current link quality of a data communication channel, according to method steps of claim 1.

9. A program storage device readable by computer, tangibly embodying a program of instructions executable by the computer to perform method steps for adapting a first and second transmission parameters in a transmitting node of a data communication system to the current link quality of a data communication channel, said method steps comprising the steps of claim 1.

10. A program storage device readable by the computer, tangibly embodying a program of instructions executable by the computer to perform method steps for adapting a first and second transmission parameters in a transmitting node of a data communication system to the current link quality of a data communication channel, said method steps comprising the steps of claim 2.

11. A program storage device readable by computer, tangibly embodying a program of instructions executable by the computer to perform method steps for adapting a first and second transmission parameters in a transmitting node of a data communication system to the current link quality of a data communication channel, said method steps comprising the steps of claim 3.

12. A program storage device readable by computer, tangibly embodying a program of instructions executable by the computer to perform method steps for adapting a first and second transmission parameters in a transmitting node of a data communication system to the current link quality of a data communication channel, said method steps comprising the steps of claim 4.

13. An apparatus for adapting a first and second transmission parameters in a transmitting node of a data communication system to the current link quality of a data communication channel, the apparatus comprising:

a success counter for counting the number of successful transmissions, each successful transmission bases on a receipt of an acknowledgment;

a comparison unit for comparing the number of successful transmissions against a threshold value;

a critical mode register for storing a critical value that due to the current link quality corresponds to a temporarily unsupported rate and power value of one of the first and second transmission parameters; and

a decision unit for jointly adapting both of the first and second transmission parameters in dependence on the critical value stored in the critical mode register, wherein said jointly adapting includes one of;

supporting a highest possible data rate by increasing a data rate transmission until a maximum rate is found, and if said rate cannot be increased further, reducing said transmit power level;

or, supporting a lowest possible transmit power level by decreasing a power transmission level until a power level can not be further reduced and to increase the transmit rate when the transmit power level can not be further decreased.

14. An apparatus according to claim 13, further comprising a delay value counter for counting a number of faulty transmissions.

15. An apparatus according to claim 13, further comprising a delay value counter for counting a delay value.

16. A computer program product comprising a computer usable medium having computer readable program code means embodied therein for causing adaptation of a first and second transmission parameters in a transmitting node of a data communication system to the current link quality of a data communication channel, the computer readable program code means in said computer program product comprising computer readable program code means for causing a computer to effect the functions of claim 15.

17. An article of manufacture comprising a computer usable medium having computer readable program code means embodied therein for causing adaptation of first and second transmission parameters in a transmitting node of a data communication system to the current link quality of a data communication channel, the computer readable program code means in said article of manufacture comprising computer readable program code means for causing a computer to effect in the transmitting node the steps of:

counting the number of successful transmissions, each successful transmission bases on a receipt of an acknowledgment;

comparing the number of successful transmissions against a threshold value; and

in the event of achieving the number of successful transmissions with the threshold value and operating with the first and second transmission parameter in a predetermined parameter space,

jointly adapting both of the first and second transmission parameters in dependence on a critical value that due to the current link quality corresponds to a temporarily unsupported rate and power value of one of the first and second transmission parameters, wherein said jointly adapting includes one of supporting a highest possible data rate by increasing a data rate transmission until a maximum rate is found, and if said rate cannot be increased further, reducing said transmit power level;

or, supporting a lowest possible transmit power level by decreasing a power transmission level until a power level can not be further reduced and to increase the transmit rate when the transmit power level can not be further decreased.