Apparatus, and associated method, for operating upon packet data communicated in a packet communication system utilizing a packet retransmission scheme

• US 7,209,483 B2
• Filed: 02/19/2002
• Issued: 04/24/2007
• Est. Priority Date: 02/19/2002
• Status: Expired due to Fees

• Current Assignee: Nokia Technologies Oy (Nokia Corporation)
• Original Assignee: Nokia Corporation
• Inventors: Tran, Jean-Marie, Kenney, Thomas
• Primary Examiner(s): Chan; Wing
• Assistant Examiner(s): Haliyur; Venkatesh
• Application Number:
  US10/078,139
• Publication Number:
  US 20030156573A1
• Time in Patent Office: 1,890 Days
• Field of Search: 370/394, 370/474, 370/338, 370/349, 370/332, 370/333, 714/746, 714/748, 714/749
• US Class Current: 370/394
• 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 1/005 Iterative decoding, including iteration between signal detection and decoding operation
• CPC Class Codes: H04L 1/16 in which the return channel carries supervisory signals, e.g. repetition request signals
• CPC Class Codes: H04L 1/1816 with retransmission of the same, encoded, message
• CPC Class Codes: H04L 1/1845 Combining techniques, e.g. code combining

Abstract

Apparatus, and an associated method, for a packet radio communication system that utilizes a packet retransmission scheme. A data packet, together with a selected number of retransmissions thereof are sent to a mobile station, or other receiving station. A channel condition estimator estimates channel conditions on the communication channel and, responsive to the channel condition estimates, selection is made of the number of packet data retransmissions that are to be effectuated prior to performing decoding operations to recover the informational content of the data packet.

Claims

1. In a packet communication system in which packet data is communicated to a first communication station pursuant to an ARQ retransmission scheme upon a communication channel by a second communication station, an improvement of apparatus for the first communication station for facilitating recovery of values of a data packet communicated to the first communication station, said apparatus comprising:

a data packet combiner block coupled to receive at least a selected data packet of the packet data together with at least a selected number of retransmissions of the selected data packet, said data packet combiner at least for buffering the selected data packet and the selected number of retransmissions thereof;

a decoder coupled to said data packet combiner, said decoder selectably for recovering values of the selected data packet and the selected number of retransmissions thereof, said decoder for selectably decoding the values provided thereto to form a decoded representation of the selected data packet; and

a controller coupled to receive indications of channel conditions of the communication channel, said controller operable responsive to the indications of the channel conditions for selecting the selected number of retransmissions buffered at said packet data combiner, together to be provided to said decoder prior to decoding.

2. The apparatus of claim 1 wherein said controller further indicates generation of NAK (negative acknowledgment) messages for return to the second communication station until the selected number of retransmissions of the selected data packet are buffered at said data packet combiner.

3. The apparatus of claim 1 wherein said controller further initiates generation of ACK (acknowledgment) messages for return to the second communication station when the selected number of retransmissions of the selected data packet are buffered at said packet data combiner.

4. The apparatus of claim 1 wherein the selected number of retransmissions of the selected data packet selected by said controller to be at least buffered at said data packet combiner comprises a fixed number.

5. The apparatus of claim 1 wherein the selected number of retransmissions of the selected data packet selected by said controller to be at least buffered at said data packet combiner comprises an adaptively-determined number.

6. The apparatus of claim 5 wherein the adaptively-determined number selected by said controller is selected responsive to values of the indications of the channel conditions.

7. The apparatus of claim 6 wherein the adaptively-determined number selected by said controller is selected responsive to a cumulative value of the indications of the channel conditions.

8. The apparatus of claim 7 wherein the cumulative value of the indications of the channel conditions responsive to which said controller selects the adaptively-determined number comprises a summation of successive values determined at successive deliveries to the first communication station of retransmissions of the selected data packet.

9. The apparatus of claim 8 wherein said controller selects the selected number of retransmissions buffered at said packet data combiner by comparing the cumulative value subsequent to each retransmission of the selected data packet with a threshold value.

10. The apparatus of claim 9 wherein said controller further initiates decoding by said decoder of the selected data packet together with the selected number of retransmissions thereof when the cumulative value is at least as great as the threshold value.

11. The apparatus of claim 6 wherein said controller selects the selected number of retransmissions buffered at said packet data responsive to a noncumulative value of the indications of the channel conditions.

12. The apparatus of claim 11 wherein said controller further initiates decoding by said decoder of the selected data packet together with the selected number of retransmissions thereof when the cumulative value is at least as great as a selected threshold value.

13. The apparatus of claim 1 wherein said controller selectably further initiates generation of an ACK (acknowledgment) message upon successful decoding operations performed by said decoder.

14. The apparatus of claim 11 wherein selection by said controller to initiate the generation of the ACK message is made responsive to a redundancy code check made with part of the decoded representation formed by said decoder.

15. The apparatus of claim 1 wherein the packet communication system comprises a packet radio communication system, wherein the first communication station comprises a mobile station, and wherein said packet data combiner, said decoder, and said controller comprise portions of the mobile station.

16. In a method for communicating in a packet communication system in which packet data is communicated to a first communication station pursuant to an ARQ retransmission scheme upon a communication channel by a second communication station, an improvement of a method for the first communication station for facilitating recovery of values of a data packet communicated to the first communication station, said method comprising:

buffering a selected data packet of the packet data transmitted to the first communication station;

selecting a selected number of retransmissions of the selected data packet to be transmitted to the first communication station responsive to indications of channel conditions of the communication channel prior to decoding;

further buffering the retransmissions of the selected data packet;

selectably decoding the selected data packet together with the selected number of retransmissions thereof.

17. The method of claim 16 wherein the selected number of retransmissions selected during said operation of selecting the selected number of retransmissions is an adaptively determined value.

18. The method of claim 17 wherein the adaptively-determined value is selected responsive to a cumulative value of the indications of the channel conditions.

19. The method of claim 18 wherein the selected number of retransmissions selected during said operation of selecting comprises a single retransmission set and wherein said operations of selecting and further buffering are iteratively performed.

20. The method of claim 19 wherein said operation of decoding is performed subsequent to selection during said operation of selecting not to retransmit an additional retransmission of the selected data packet.