METHOD AND APPARATUS FOR OPTIMIZING A RETRY LIMIT FOR MULTIMEDIA SYSTEMS THAT ARE PRONE TO ERRORS

• US 20100162070A1
• Filed: 12/19/2008
• Published: 06/24/2010
• Est. Priority Date: 12/19/2008
• Status: Abandoned Application

• Current Assignee: Qualcomm, Inc.
• Original Assignee: Qualcomm, Inc.
• Inventors: Rajamani, Krishnan, Das, Soumya
• Application Number:
  US12/340,249
• Publication Number:
  US 20100162070A1
• Time in Patent Office: Days
• US Class Current: 714/751
• CPC Class Codes: H04L 1/0018 based on latency requirement
• CPC Class Codes: H04L 1/1825 Adaptation of specific ARQ protocol parameters according to transmission conditions
• CPC Class Codes: H04L 1/1877 for semi-reliable protocols, e.g. for less sensitive applications like streaming video buffer level management for video bitstream control arrangements H04N21/44004

Abstract

Devices, systems and methods for optimizing a number of retransmission attempts in a multimedia environment and managing delays in a host MAC layer. In its various aspects, the presently claimed invention includes several methodologies and systems that are configured for determining an optimal retry limit in response to one or both of a packet error rate bound and a latency bound. To the extent that the retry limit is determined with respect to one of the aforementioned boundaries, the presently claimed invention may include determining a confidence level that the non-selected bound will also be met by the selected retry limit. The presently claimed invention details devices, systems and methods optimizing the number of retransmission attempts to ensure delivery of the selected data packets while guarding against undue delays and application disruptions.

Claims

1. A method of optimizing a retry limit for retransmitted packets in a medium access control (MAC) layer defining a latency bound and a packet error rate (PER) bound for an application, the method comprising the steps of:

setting the retry limit in response to one of the latency bound or the PER bound;

estimating a confidence level for achieving a bound for a nonselected one of the latency bound or the PER bound; and

retransmitting the packets in accordance with the retry limit.

2. The method of claim 1, further comprising the step comparing the confidence level to a CL threshold value.

3. The method of claim 2, further comprising the steps of computing an aggregate latency across one or more preceding application frames and comparing the aggregate latency to an aggregate latency threshold value.

4. The method of claim 3, further comprising the step of adjusting one or more transmission parameters in response to one of the confidence level decreasing below the CL threshold value or the aggregate latency exceeding the aggregate latency threshold value.

5. The method of claim 4, wherein the one or more transmission parameters comprise:

a MAC reservation capacity, a MAC fragmentation threshold, an application bit rate, an application frame rate, a PHY rate and a PHY transmission power.

6. A method of optimizing a retry limit for retransmitted packets in a medium access control (MAC) layer, the method comprising the steps of:

setting a packet error rate (PER) bound;

setting the retry limit in response to the PER bound;

estimating a confidence level of a latency bound in response to the retry limit and the PER bound; and

retransmitting the packets in response to the retry limit and the confidence level.

7. The method of claim 6, further comprising the step of comparing the confidence level to a CL threshold value.

8. The method of claim 7, further comprising the steps of computing an aggregate latency across one or more preceding application frames and comparing the aggregate latency to an aggregate latency threshold value.

9. The method of claim 8, further comprising the step of adjusting one or more transmission parameters in response to one of the confidence level decreasing below the CL threshold value or the aggregate latency exceeding the aggregate latency threshold value.

10. The method of claim 9, wherein the one or more transmission parameters comprise:

a MAC reservation capacity, a MAC fragmentation threshold, an application bit rate, an application frame rate, a PHY rate and a PHY transmission power.

11. A method of optimizing the retry limit for retransmitted packets in a wireless communications system, the method comprising the steps of:

providing a media access control layer;

transmitting data packets from a wireless modem to a display;

calculating a retry limit range from a first retry limit derived from a packet error rate (PER) bound and a second retry limit derived from a latency bound;

in response to the first retry limit being less than or equal to the second retry limit, retransmitting non-acknowledged data packets; and

in response to the first retry limit being greater than the second retry limit, adjusting one or more transmission parameters.

12. The method of claim 11, wherein the one or transmission parameters comprise:

a MAC reservation capacity, a MAC fragmentation threshold, an application bit rate, an application frame rate, a PHY rate and a PHY transmission power.

13. A method of partitioning a total delay budget for MAC transmissions comprising:

calculating a total delay budget for a single transmission delay portion for any single application frame, an aggregate delay portion for a predetermined number of preceding application frames, and a processing delay portion;

calculating a retry limit bound for the single transmission delay portion as a function of one or more of a packet error rate (PER) bound or a latency bound;

transmitting one or more frames in accordance with the retry limit bound and the aggregate delay portion; and

prospectively adjusting one or more transmission parameters in response the retry limit exceeding the retry limit bound or the aggregate delay portion exceeding an aggregate delay threshold.

14. The method of claim 13, wherein the step of calculating a retry limit bound comprises setting the retry limit in response to one of the latency bound or the PER bound, estimating a confidence level for achieving a bound for a nonselected one of the latency bound or the PER bound, and retransmitting the packets in accordance with the retry limit.

15. The method of claim 13, wherein the step of calculating a retry limit bound comprises setting a packet error rate (PER) bound, setting the retry limit in response to the PER bound, estimating a confidence level of a latency bound in response to the retry limit and the PER bound, and retransmitting the packets in response to the retry limit.

16. The method of claim 13, wherein the step of calculating a retry limit bound comprises calculating a retry limit range from a first retry limit derived from a packet error rate (PER) bound and a second retry limit derived from latency bound.

17. The method of claim 13, wherein the one or more transmission parameters comprise:

a MAC reservation capacity, a MAC fragmentation threshold, an application bit rate, an application frame rate, a PHY rate and a PHY transmission power.

18. A storage media comprising program instructions which are computer-executable to implement optimization of a retry limit for retransmitted packets in a medium access control (MAC) layer defining a latency bound and a packet error rate (PER) bound for an application, the storage media comprising:

program instructions that cause a retry limit to be set in response to one of the latency bound or the PER bound;

program instructions that cause a confidence level to be estimated for achieving a bound for a nonselected one of the latency bound or the PER bound; and

program instructions that cause the packets to be retransmitted in accordance with the retry limit.

19. The storage media of claim 18, further comprising program instructions to compare the confidence level to a CL threshold value.

20. The storage media of claim 19, further comprising program instructions to compute an aggregate latency across one or more preceding application frames and compare the aggregate latency to an aggregate latency threshold value

21. The storage media of claim 20, further comprising program instructions to adjust one or more transmission parameters in response to one of the confidence level decreasing below the CL threshold value or the aggregate latency exceeding the aggregate latency threshold value.

22. The storage media of claim 21, wherein the one or more transmission parameters comprise:

a MAC reservation capacity, a MAC fragmentation threshold, an application bit rate, an application frame rate, a PHY rate and a PHY transmission power.

23. A storage media comprising program instructions which are computer-executable to implement optimization of a retry limit for retransmitted packets in a medium access control (MAC) layer, the storage media comprising:

program instructions to set a packet error rate (PER) bound;

program instructions to set the retry limit in response to the PER bound;

program instructions to estimate a confidence level of a latency bound in response to the retry limit and the PER bound; and

program instructions to retransmit the packets in response to the retry limit and the confidence level.

24. The storage media of claim 23, further comprising program instructions to compare the confidence level to a CL threshold value.

25. The storage media of claim 24, further comprising program instructions to compute an aggregate latency across a predetermined number of frames and compare the aggregate latency to an aggregate latency threshold value.

26. The storage media of claim 24, further comprising program instructions to adjust one or more transmission parameters in response to one of the confidence level decreasing below the CL threshold value or the aggregate latency exceeding the aggregate latency threshold value.

27. The storage media of claim 26, wherein the one or more transmission parameters comprise:

a MAC reservation capacity, a MAC fragmentation threshold, an application bit rate, an application frame rate, a PHY rate and a PHY transmission power.

28. A storage media comprising program instructions which are computer-executable to implement an optimization of a retry limit for retransmitted packets in a wireless communications system, the storage media comprising:

program instructions comprising a provision of a media access control layer;

program instructions to transmit data packets from a wireless modem to a display;

program instructions to calculate a retry limit range from a first retry limit derived from a packet error rate (PER) bound and a second retry limit derived from a latency bound;

program instructions to retransmit non-acknowledged data packets in response to the first retry limit being less than or equal to the second retry limit and adjust one or more transmission parameters in response to the first retry limit being greater than the second retry limit; and

program instructions to adjust one or more transmission parameters in response to the first retry limit being greater than the second retry limit.

29. The storage media of claim 28, wherein the one or more transmission parameters comprise:

a MAC reservation capacity, a MAC fragmentation threshold, an application bit rate, an application frame rate, a PHY rate and a PHY transmission power.

30. A storage media comprising program instructions which are computer-executable to implement partitioning a total delay budget for MAC transmissions, the storage media comprising:

program instructions to calculate a total delay budget for a single transmission delay portion for any single application frame, an aggregate delay portion for a predetermined number of preceding application frames, and a processing delay portion;

program instructions to calculate a retry limit bound for the single transmission delay portion as a function of one or more of a packet error rate (PER) bound or a latency bound;

program instructions to transmit one or more frames in accordance with the retry limit bound and the aggregate delay portion; and

program instructions to prospectively adjust one or more transmission parameters in response the retry limit exceeding the retry limit bound the aggregate delay portion exceeding an aggregate delay threshold.

31. The storage media of claim 30, wherein the program instructions to calculate a retry limit bound comprises program instructions to set the retry limit in response to one of the latency bound or the PER bound, program instructions to estimate a confidence level for achieving a bound for a nonselected one of the latency bound or the PER bound, and program instructions to retransmit the packets in accordance with the retry limit.

32. The storage media of claim 30, wherein the program instructions to calculate a retry limit bound comprises program instructions to set a packet error rate (PER) bound, program instructions to set the retry limit in response to the PER bound, program instructions to estimate a confidence level of a latency bound in response to the retry limit and the PER bound, and program instructions to retransmit the packets in response to the retry limit.

33. The storage media of claim 30, wherein the program instructions to calculate a retry limit bound comprises program instructions to calculate a retry limit range from a first retry limit derived from a packet error rate (PER) bound and a second retry limit derived from a latency bound.

34. The storage media of claim 30, wherein the one or more transmission parameters comprise:

a MAC reservation capacity, a MAC fragmentation threshold, an application bit rate, an application frame rate, a PHY rate and a PHY transmission power.

35. An apparatus operable with a medium access control (MAC) layer, the apparatus comprising:

a wireless modem adapted to transmit a wireless signal comprising a plurality of packets to a display; and

a controller connected to the wireless modem, the controller adapted to set a retry limit in response to one of a latency bound or a PER bound;

estimate a confidence level for achieving a bound for a nonselected one of the latency bound or the PER bound; and

retransmit the packets in accordance with the retry limit.

36. The apparatus of claim 35, wherein the controller is further adapted to compare the confidence level to a CL threshold value.

37. The apparatus of claim 36, wherein the controller is further adapted to compute an aggregate latency across a predetermined number of application frames and compare the aggregate latency to an aggregate latency threshold value.

38. The apparatus of claim 37, wherein the controller is further adapted to adjust one or more transmission parameters in response to one of the confidence level decreasing below the CL threshold value or the aggregate latency exceeding the aggregate latency threshold value.

39. The apparatus of claim 38, wherein the one or more transmission parameters comprise:

a MAC reservation capacity, a MAC fragmentation threshold, an application bit rate, an application frame rate, a PHY rate and a PHY transmission power.

40. An apparatus operable with a medium access control (MAC) layer, the apparatus comprising:

a wireless modem adapted to transmit a wireless signal comprising a plurality of packets to a display; and

a controller connected to the wireless modem, the controller adapted to set a packet error rate (PER) bound, set a retry limit in response to the PER bound, estimate a confidence level of a latency bound in response to the retry limit and the PER bound, and retransmit the packets in response to the retry limit and the confidence level.

41. The apparatus of claim 40, wherein the controller is further adapted to compare the confidence level to a CL threshold value.

42. The apparatus of claim 41, wherein the controller is further adapted to compute an aggregate latency across a predetermined number of application frames and compare the aggregate latency to an aggregate latency threshold value.

43. The apparatus of claim 42, wherein the controller is further adapted to adjust one or more transmission parameters in response to one of the confidence level decreasing below the CL threshold value or the aggregate latency exceeding the aggregate latency threshold value.

44. The apparatus of claim 43, wherein the one or more transmission parameters comprise:

a MAC reservation capacity, a MAC fragmentation threshold, an application bit rate, an application frame rate, a PHY rate and a PHY transmission power.

45. A system for optimizing a retry limit for retransmitted packets in a wireless communications network, the system comprising:

a wireless modem configured for operation with a media access control layer and adapted to transmit data packets to a display in accordance with one or more transmission parameters; and

a controller connected to the wireless modem and adapted to calculate a retry limit range from a first retry limit derived from a packet error rate (PER) bound and a second retry limit derived from latency bound;

wherein, in response to the first retry limit being less than or equal to the second retry limit, the controller is adapted to retransmit non-acknowledged data packets; and

in response to the first retry limit being greater than the second retry limit, the controller is adapted to adjust one or more transmission parameters.

46. The system of claim 45, wherein the one or more transmission parameters comprise:

a MAC reservation capacity, a MAC fragmentation threshold, an application bit rate, an application frame rate, a PHY rate and a PHY transmission power.

47. A controller configured for partitioning a total delay budget for MAC transmissions comprising:

means for calculating a total delay budget for a single transmission delay portion for any single application frame, an aggregate delay portion for a predetermined number of preceding application frames, and a processing delay portion;

means for calculating a retry limit bound for the single transmission delay portion as a function of one or more of a packet error rate (PER) bound or a latency bound;

means for transmitting one or more frames in accordance with the retry limit bound and the aggregate delay portion; and

means for prospectively adjusting one or more transmission parameters in response the retry limit exceeding the retry limit bound the aggregate delay portion exceeding an aggregate delay threshold.

48. The controller of claim 47, wherein the means for calculating a retry limit bound comprises means for setting the retry limit in response to one of the latency bound or the PER bound, means for estimating a confidence level for achieving a bound for a nonselected one of the latency bound or the PER bound, and means for retransmitting the packets in accordance with the retry limit.

49. The controller of claim 47, wherein the means for calculating a retry limit bound comprises means for setting a packet error rate (PER) bound, means for setting the retry limit in response to the PER bound, means for estimating a confidence level of a latency bound in response to the retry limit and the PER bound, and means for retransmitting the packets in response to the retry limit.

50. The controller of claim 47, wherein the means for calculating a retry limit bound comprises means for calculating a retry limit range from a first retry limit derived from a packet error rate (PER) bound and a second retry limit derived from latency bound.

51. The controller of claim 47, wherein the one or more transmission parameters comprise:

a MAC reservation capacity, a MAC fragmentation threshold, an application bit rate, an application frame rate, a PHY rate and a PHY transmission power.