AUTOMATIC REPEAT REQUEST (ARQ) SCHEME

• US 20070250751A1
• Filed: 04/19/2006
• Published: 10/25/2007
• Est. Priority Date: 04/19/2006
• Status: Active Grant

• Current Assignee: Google Technology Holdings LLC (Alphabet Inc.)
• Original Assignee: Motorola, Inc. (Motorola Solutions, Inc.)
• Inventors: Cai, Zhijun, Ahmed, Mansoor, Reed, John
• Granted Patent: US 7,502,981 B2
• Time in Patent Office: Days
• US Class Current: 714/748
• CPC Class Codes: H04L 1/008 where the control data relates to payload of a different packet
• CPC Class Codes: H04L 1/08 by repeating transmission, e.g. Verdan system H04L1/1858 and H04L1/189 take precedence
• CPC Class Codes: H04L 1/1607 Details of the supervisory signal
• CPC Class Codes: H04L 2001/125 Arrangements for preventing errors in the return channel

Abstract

During operation each ACK/NAK feedback (200) comprises two fields (201-204). Each field corresponds to the status of previously-received data (e.g., slot, frame, TTI, . . . , etc.). In a first embodiment, field 1 corresponds to the current received data status, while field 2 corresponds to the previous received data status if a NAK misinterpretation error occurs. If the receiver detects no misinterpretation error, the second field is simply left blank. Because each ACK/NAK feedback will comprise the reception status of currently received data, and prior-received data, a transmitter has two chances to receive the NAK/ACK if a NAK misinterpretation error occurs.

Claims

1. A method for performing ARQ, the method comprising the steps of:

transmitting a current block of data;

receiving an ACK/NAK feedback, the ACK/NAK feedback comprising at least a first and a second field, wherein the first field represents an ACK/NAK status of the current block of data, and the second field represents an ACK/NAK status of a previous block of data; and

retransmitting the current block of data or the previous block of data based on the first and the second fields.

2. The method of claim 1 wherein the current block of data comprises a current TTI, the previous block of data comprises a previous TTI.

3. The method of claim 1 wherein the current block of data and the previous block of data comprises encoded data.

4. The method of claim 1 further comprising the step of:

transmitting new-data indicator (NDI) bits on the status of the current block of data, the NDI bits indicating whether the current block of data comprises new data, the retransmission of the last TTI, or the retransmissions of the one before the last.

5. A method for performing ARQ, the method comprising the steps of:

receiving a current block of data;

determining if the current block of data is received in error;

determining if the current block of data is new;

determining if a previously-received block of data was received in error; and

transmitting an ACK/NAK feedback comprising at least a first and a second field, wherein the first field represents an ACK/NAK status of the current block of data, and the second field represents an ACK/NAK status of a previous block of data.

6. The method of claim 5 wherein a NAK is transmitted in the second field if the current block of data is new and the previously-received block of data was received in error.

7. The method of claim 5 wherein transmitting an ACK/NAK feedback in the second field comprises transmitting an On-Off-Keying (OOK) transmission in the second field.

8. The method of claim 5 wherein the current block of data comprises a current TTI, and the previously-received block of data comprises a previously-received TTI.

9. The method of claim 5 wherein the current block of data and the previously-received block of data comprises encoded data.

10. The method of claim 5 further comprising the step of:

receiving a new-data indicator (NDI); and

wherein the step of determining if the current block of data is new comprises the step of determining if the current block of data is new, or the retransmission of the last TTI, or the retransmissions of the one before the last, based on the NDI.

11. An apparatus comprising:

a transmitter transmitting an ACK/NAK feedback comprising at least a first and a second field, wherein the first field represents an ACK/NAK status of the current block of data, and the second field represents an ACK/NAK status of a previous block of data.

12. The apparatus of claim 11 further comprising:

a receiver receiving a current block of data; and

logic circuitry determining if the current block of data is received in error, determining if the current block of data is new, and determining if a previously-received block of data was received in error.

13. The apparatus of claim 12 wherein a NAK is transmitted in the second field if the current block of data is new and the previously-received block of data was received in error.

14. The apparatus of claim 12 wherein the current block of data comprises a current TTI, and the previously-received block of data comprises a previously-received TTI.

15. The apparatus of claim 12 wherein the current block of data and the previously-received block of data comprises encoded data.

16. The apparatus of claim 12 wherein the receiver additionally receives a new-data indicator (NDI), and the logic circuitry determines if the current block of data is new, the retransmission of the last TTI, or the retransmissions of the one before the last, based on the NDI.

17. An apparatus comprising:

a receiver receiving an ACK/NAK feedback, the ACK/NAK feedback comprising at least a first and a second field, wherein the first field represents an ACK/NAK status of a current block of data, and the second field represents an ACK/NAK status of a previous block of data; and

a transmitter retransmitting the current block of data or the previous block of data or a new block of data based on the first and the second fields.

18. The apparatus of claim 17 wherein the current block of data comprises a current TTI, the previous block of data comprises a previous TTI, and the new block of data comprises a new TTI.

19. The apparatus of claim 17 wherein the block of data comprises encoded data.

20. The apparatus of claim 17 wherein the transmitter additionally transmits a new-data indicator (NDI) if the current block of data is new data, the retransmission of the last TTI, or the retransmissions of the one before the last.