Flexible ARQ for packet data transmission

• US 20050094667A1
• Filed: 11/15/2004
• Published: 05/05/2005
• Est. Priority Date: 07/24/2000
• Status: Abandoned Application

• Current Assignee: Telefonaktiebolaget LM Ericsson
• Original Assignee: Telefonaktiebolaget LM Ericsson
• Inventors: Dahlman, Erik, Parkvall, Stefan
• Application Number:
  US10/986,977
• Publication Number:
  US 20050094667A1
• Time in Patent Office: Days
• US Class Current: 370/473
• CPC Class Codes: H04L 1/1803 Stop-and-wait protocols
• CPC Class Codes: H04L 1/1819 with retransmission of additional or different redundancy
• CPC Class Codes: H04L 1/187 Details of sliding window management
• CPC Class Codes: H04L 1/1874 Buffer management
• CPC Class Codes: H04L 1/188 Time-out mechanisms

Abstract

The present invention provides a flexible ARQ scheme. A communications channel is set up between a transmitter and a receiver. A value is selected for an ARQ parameter for data packets to be transmitted over the communications channel. The ARQ parameter value may be selected in accordance with a trade-off between a desired performance or goal, e.g., a specific throughput of data packets transmitted over the communications channel, and one or more communication resources required to support the desired performance or goal. An example of an ARQ parameter is a number of outstanding data packets to be acknowledged by the receiver before more packets can be sent to the receiver. Another parameter example is a delay associated with the ARQ scheme. In a preferred, non-limiting example embodiment, first and second ARQ parameter values are selected for a desired trade-off Accordingly, a specific number of outstanding data packets to be acknowledged by the receiver and an acknowledgement or retransmission delay can be selected to achieve a desired performance, e.g., a desired throughput of data packets, at a particular resource cost. Because of the flexibility provided by the present invention, a communications device may set its own objectives for a particular connection based upon one or more performance requirements, communication resources, or other requirements.

Claims

1. For use in a wireless communications system, a method for acknowledged packet data communications between a sender and a receiver, comprising:

detecting a request to establish a packet data communication between the transmitter and the receiver where sent data packets are acknowledged when received by the receiver, and

determining a value of a first parameter for a packet data acknowledgment procedure for the packet data communication so that a communication resource is efficiently used in supporting the packet acknowledgment procedure.

3. The method in claim 1, wherein the communication resource includes a data processing speed requirement to support the acknowledgment of sent data packets.

4. The method in claim 1, wherein the communication resource includes a buffering requirement to support the acknowledgment of sent data packets.

6. The method in claim 1, wherein the value of the first parameter is determined when the packet data communication is established.

8. The method in claim 1, wherein the value of the first parameter is determined to achieve a desired, throughput of packet data for the packet data communication.

9. The method in claim 1, wherein the first parameter value is a number of outstanding data packets transmitted to the receiver by the sender to be acknowledged by the receiver.

10. The method in claim 1, wherein the first parameter is a delay time associated with the packet acknowledgement procedure.

11. The method in claim 10, wherein the delay time is an acknowledgement delay denoting a time period between sending a data packet and acknowledgement of receipt of that data packet.

12. The method in claim 11, wherein the acknowledgment delay includes a time to transmit the data packet, process the data packet at the receiver, and receive an acknowledgment.

13. The method in claim 11, wherein the sender resends the data packet if the acknowledgment is not received within the acknowledgment delay.

14. The method in claim 10, wherein the delay time is a retransmission delay denoting a time period between sending a data packet and retransmission of that data packet if that data packet needs to be retransmitted.

15. The method in claim 14, wherein the acknowledgment delay includes a time to transmit the data packet, process the data packet at the receiver, and receive an acknowledgment.

16. The method in claim 14, wherein the sender resends the data packet if the packet to be retransmitted is not retransmitted within the retransmission delay.

17. The method in claim 10, further comprising:

storing in the transmitter n transmitted data packets, and resending the n transmitted data packets if the acknowledgment is not received within the delay period.

19. The method in claim 10, further comprising:

selecting a smaller number of outstanding packets and a larger delay to reduce buffering requirements and required data processing speed in the receiver.

20. The method in claim 10, further comprising:

selecting a larger number of outstanding packets and a smaller delay to increase throughput for the packet data communication.

21. The method in claim 10, further comprising:

selecting a larger number of outstanding packets and a larger delay to increase throughput for the packet data communication.

22. The method in claim 10, further comprising:

selecting a larger delay when communicating over a larger distance as compared to communicating over a smaller distance.

23. The method in claim 22, wherein the larger distance corresponds to a macrocell and the smaller distance corresponds to a microcell.

58. The method in claim 1, wherein the wireless communications system is a radio communications system.

2. (canceled)

24. The method in claim 2, further comprising:

changing only the first parameter or the second parameter while keeping the other parameter constant.

5. (canceled)

7. (canceled)

18. (canceled)

25. A method for reliable wireless data communications between a transmitter and a receiver comprising:

setting up a wireless communication channel between the transmitter and the receiver;

selecting a value of a first parameter of a reliable data packet delivery procedure (RDPDP) for data packets transmitted over the wireless communication channel,

wherein the first parameter value is selected for a desired tradeoff between a performance associated with the communication and one or more RDPDP resources required to support the performance.

26. The method in claim 25, wherein the first parameter is a number of outstanding data packets to be acknowledged by the receiver.

27. The method in claim 25, wherein the first parameter is a delay associated with the RDPDP.

30. The method in claim 25, wherein the one or more RDPDP resources includes an RDPDP buffering requirement.

31. The method in claim 25, wherein the one or more RDPDP resources includes an RDPDP data processing speed.

33. The method in claim 25, wherein the performance is a specific throughput of data packets transmitted over the communications channel.

59. The method in claim 25, wherein the wireless communications system is a radio communications system.

28. (canceled)

29. (canceled)

32. (canceled)

34. For use in a wireless communications system where a packet communication is requested between a transmitter and a receiver of the wireless communications system, apparatus for use in the receiver, comprising:

a buffer storing data packets received from the transmitter, and

a controller processing received packets stored in the buffer and sending an acknowledgement signal for each received packet in accordance with a data packet acknowledgement procedure,

wherein for a particular communication with a transmitter, the controller determines a value of a first parameter affecting a performance of the data packet acknowledgement procedure.

36. The apparatus in claim 34, wherein a characteristic of the performance is a buffering capacity required for the controller to process and acknowledge received packets.

37. The apparatus in claim 34, wherein a characteristic of the performance is a processing speed required for the controller to process and acknowledge received packets.

38. The apparatus in claim 34, wherein a characteristic of the performance is a data throughput desired for the data packet communication with the receiver.

39. The apparatus in claim 34, wherein the first parameter value is a number of outstanding data packets transmitted to the receiver by the transmitter to be acknowledged by the receiver.

40. The apparatus in claim 34, wherein the first parameter is a delay associated with a data packet acknowledgement procedure.

41. The apparatus in claim 40, wherein the delay is an acknowledgment delay denoting a time period between sending a data packet and acknowledgment of receipt of that data packet.

42. The apparatus in claim 41, wherein the acknowledgment delay includes a time to transmit the data packet, process the data packet at the receiver, and receive an acknowledgment.

43. The apparatus in claim 40, wherein the delay is a retransmission delay denoting a time period between sending a data packet and retransmission of that data packet if that data packet requires retransmission.

44. The apparatus in claim 34, wherein the value of the first parameter is determined when the data packet communication is established.

46. The apparatus in claim 34, wherein the value of the first parameter is negotiated by the receiver with the transmitter.

53. The apparatus in claim 34, wherein the receiver is a wireless user equipment.

54. The apparatus in claim 34, wherein the receiver is a radio base station.

55. The apparatus in claim 34, wherein the receiver is coupled to the transmitter by way of a wire or optical fiber link.

56. A receiver with the apparatus claimed in any of claims 34, 39, or 40.

57. A transmitter configured to communicate with the receiver including the apparatus as claimed in any of claims 34, 39, or 40.

60. The apparatus in claim 34, wherein the wireless communications system is a radio communications system.

35. (canceled)

45. (canceled)

47-52. -52. (canceled)