Detection and recovery of HARQ NAK-TO-ACK feedback error in wireless communications systems

• US 20100005354A1
• Filed: 12/22/2008
• Published: 01/07/2010
• Est. Priority Date: 07/07/2008
• Status: Active Grant

• Current Assignee: Intel Corporation
• Original Assignee: Intel Corporation
• Inventors: Yang, Xiangying, Yin, Hujun, Zhu, Yuan
• Granted Patent: US 8,959,409 B2
• Time in Patent Office: Days
• US Class Current: 714/749
• CPC Class Codes: H04L 1/08 by repeating transmission, e.g. Verdan system H04L1/1858 and H04L1/189 take precedence
• CPC Class Codes: H04L 1/14 in which the signals are sent back to the transmitter to be checked ; echo systems
• CPC Class Codes: H04L 1/1812 Hybrid protocols; Hybrid automatic repeat request [HARQ]
• CPC Class Codes: H04L 1/1825 Adaptation of specific ARQ protocol parameters according to transmission conditions
• CPC Class Codes: H04L 1/1864 ARQ related signaling H04L1/1607 takes precedence
• CPC Class Codes: H04L 1/1887 Scheduling and prioritising arrangements
• CPC Class Codes: H04L 1/1896 ARQ related signaling
• CPC Class Codes: H04W 52/0229 where the received signal is a wanted signal
• CPC Class Codes: H04W 52/0248 dependent on the time of the day, e.g. according to expected transmission activity
• CPC Class Codes: Y02D 30/70 in wireless communication networks

Abstract

In wireless communication networks that use ARQ/HARQ feedback protocols, when a first device receives an apparent HARQ ACK from a second device, the first device may make a new transmission using a HARQ Channel ID whose previous usage was under conditions indicating a likelihood of error in the ACK. When the second device receives the new transmission, the reuse of that HARQ Channel ID in a new transmission rather than a retransmission lets the second device know that its previous NAK transmission was incorrectly received as an ACK.

Claims

1. A method, comprising:

transmitting a first transmission to a first wireless communications device, the first transmission containing a first HARQ Channel ID (ACID) and a HARQ Sequence Number (AI_SN) indicating a new transmission;

wherein the first ACID was chosen from a group of ACID'"'"'s, each of which received an ACK to its most recent transmission to the first wireless communications device;

wherein the ACK was received under conditions indicating a likelihood of error in the ACK.

2. The method of claim 1, wherein the conditions comprise a low signal-to-noise ratio for the ACK.

3. The method of claim 1, wherein the conditions comprise a low signal level for the ACK.

4. The method of claim 1, further comprising:

receiving, after transmitting the first transmission, a NAK for a previous transmission; and

retransmitting the previous transmission;

wherein the NAK conforms to Automatic Repeat Request protocols.

5. An apparatus, comprising:

a first communications device for a wireless communications network, the first device comprising a processor, a memory, and a radio, the first device to;

transmit a first transmission to a second communications device, the first transmission containing a first HARQ Channel ID (ACID) and a HARQ Sequence Number (AI_SN) indicating a new transmission;

wherein the first ACID was chosen from a group of ACID'"'"'s, each of which received an ACK to its most recent transmission to the second communications device;

wherein the ACK was received under conditions indicating a likelihood of error in the ACK.

6. The apparatus of claim 5, wherein the conditions comprise a low signal-to-noise ratio for the ACK.

7. The apparatus of claim 5, wherein the conditions comprise a low signal level for the ACK.

8. The apparatus of claim 5, wherein the first communications device is to:

receive, after transmitting the first transmission, a NAK for a previous transmission; and

retransmit the previous transmission;

wherein the NAK conforms to Automatic Repeat Request protocols.

9. An article comprising

a tangible computer-readable medium that contains instructions, which when executed by one or more processors result in performing operations comprising:

transmitting a first transmission to a first wireless communications device, the first transmission containing a first HARQ Channel ID (ACID) and a HARQ Sequence Number (AI_SN) indicating a new transmission;

wherein the first ACID was chosen from a group of ACID'"'"'s, each of which received an ACK to its most recent transmission to the first wireless communications device;

wherein the ACK was received under conditions indicating a likelihood of error in the ACK.

10. The article of claim 9, wherein the conditions comprise a low signal-to-noise ratio for the ACK.

11. The article of claim 9, wherein the conditions comprise a low signal level for the ACK.

12. The article of claim 9, further comprising:

receiving, after transmitting the first transmission, a NAK for a previous transmission; and

retransmitting the previous transmission;

wherein the NAK conforms to Automatic Repeat Request protocols.

13. A method comprising:

receiving a first transmission from a first wireless communications device, the first transmission containing a first HARQ Channel ID (ACID);

transmitting a first NAK to the first device to indicate that the first transmission was received incorrectly;

waiting for a retransmission of the first transmission;

receiving, while waiting for the retransmission, a second transmission from the first device, the second transmission containing the first ACID and an indication that the second transmission is not a retransmission of the first transmission; and

transmitting a second NAK to the first device;

wherein said transmitting the first NAK complies with Hybrid Automatic Repeat Request (HARQ) protocols and said transmitting the second NAK complies with Automatic Repeat Request (ARQ) protocols.

14. The method of claim 13, further comprising:

comparing the ACID contained in the second transmission with the ACID contained in the first transmission; and

determining the ACID in the second transmission is the same as the ACID in the first transmission.

15. The method of claim 13, wherein said determining indicates the first NAK was incorrectly received as an ACK by the first device.

16. The method of claim 13, wherein said indication that the second transmission is not a retransmission of the first transmission comprises a HARQ Sequence Number (AI_SN).

17. An apparatus, comprising:

a first communications device for a wireless communications network, the first device comprising a processor, a memory, and a radio, the first device to;

receive a first transmission from a second communications device, the first transmission containing a first HARQ Channel ID (ACID) and an indication that the first transmission is a new transmission;

compare the first ACID with a second ACID received in a previous transmission from the second communications device, to which the first communications device responded with a first NAK;

determine that the first ACID is the same as the second ACID; and

transmit a second NAK to the second communications device;

wherein the first NAK was transmitted using Hybrid Automatic Repeat Request (HARQ) protocols and the second NAK was transmitted using Automatic Repeat Request (ARQ) protocols.

18. The apparatus of claim 17, wherein the first ACK is to indicate to the second communications device that the previous transmission is to be retransmitted by the second communications device.

19. The apparatus of claim 17, wherein the indication that the first transmission is a new transmission comprises a HARQ Sequence Number (AI_SN).

20. An article comprising

a tangible computer-readable medium that contains instructions, which when executed by one or more processors result in performing operations comprising:

receiving a first transmission from a first wireless communications device, the first transmission containing a first HARQ Channel ID (ACID);

transmitting a first NAK to the first device to indicate that the first transmission was received incorrectly;

waiting for a retransmission of the first transmission;

receiving, while waiting for the retransmission, a second transmission from the first device, the second transmission containing the first ACID and an indication that the second transmission is not a retransmission of the first transmission; and

transmitting a second NAK to the first device;

wherein said transmitting the first NAK complies with Hybrid Automatic Repeat Request (HARQ) protocols and said transmitting the second NAK complies with Automatic Repeat Request (ARQ) protocols.

21. The article of claim 20, wherein the operations further comprise:

comparing the ACID contained in the second transmission with the ACID contained in the first transmission; and

determining the ACID in the second transmission is the same as the ACID in the first transmission.

22. The article of claim 20, wherein the operation of determining indicates the first NAK was incorrectly received as an ACK by the first device.

23. The article of claim 20, wherein the indication that the second transmission is not a retransmission of the first transmission comprises a HARQ Sequence Number (AI_SN).