Method of packet data transfer with hybrid ARQ

• US 20020053058A1
• Filed: 07/09/2001
• Published: 05/02/2002
• Est. Priority Date: 10/31/2000
• Status: Active Grant

• Current Assignee: LG Electronics, Inc. (LG Corporation)
• Original Assignee: LG Electronics, Inc. (LG Corporation)
• Inventors: Lee, Young Jo, Kim, Ki Jun, Kyung, Chan Ho
• Granted Patent: US 6,697,987 B2
• Time in Patent Office: Days
• US Class Current: 714/748
• CPC Class Codes: H04L 1/0013 Rate matching, e.g. puncturing or repetition of code symbols
• CPC Class Codes: H04L 1/0068 by puncturing
• CPC Class Codes: H04L 1/1671 the supervisory signal being transmitted together with control information
• CPC Class Codes: H04L 1/1816 with retransmission of the same, encoded, message
• CPC Class Codes: H04L 1/1819 with retransmission of additional or different redundancy
• CPC Class Codes: H04L 1/1825 Adaptation of specific ARQ protocol parameters according to transmission conditions
• CPC Class Codes: H04L 1/1845 Combining techniques, e.g. code combining

Abstract

A method of transmitting packet data to a receiver in a communication system using a Hybrid ARQ technique is disclosed. In accordance with one illustrative embodiment of the present invention, an index representative of how much the first packet being transmitted such as a signal-to-noise (Eb/No) ratio is compared to a predetermined threshold value when an error is occurred during the step of decoding the packet. If the index is greater than or equal to the threshold value, the first packet transmitted is stored in a buffer and a receiver requests to transmit a second additional packet encoded with a lower code rate. On the other hand, if the index is less than the threshold value, the receiver requests to re-transmit the first packet encoded with the same code rate.

Claims

1. A method of transmitting packet data to a receiver in a communication system using a Hybrid ARQ technique, the method comprising the steps of:

(a) transmitting a first packet encoded with a first code rate to a receiver;

(b) decoding said first packet in said receiver if a buffer used in said receiver is empty;

(c) comparing an index representative of how much said first packet is damaged to a predetermined threshold value if a first error is occurred during the step (b);

(d) storing said first packet in said buffer and requesting to transmit a second additional packet encoded with a second code rate if said index is greater than or equal to said threshold value, said second code rate being lower than said first code rate; and

(e) requesting to re-transmit said first packet if said index is less than said threshold value.

2. The method of claim 1, further comprising the steps of emptying said buffer and being ready for the next packet transmission if no error is occurred during the step (b).

3. The step of claim 1, wherein said first packet is self-decodable if said buffer is empty and is not self-decodable if said buffer is not empty.

4. The step of claim 1, wherein said second packet includes an error correction code.

5. The step of claim 1, wherein said index is a signal-to-noise (Eb/No) ratio of said first packet.

6. The method of claim 1, further comprising the steps of:

(f) combining said first packet with an original packet already stored in said buffer and decoding said combined packet if said buffer is not empty; and

(g) requesting to transmit said second additional packet encoded with said second code rate if a second error is occurred in the step (f).

7. The step of claim 6, further comprising the step of emptying said buffer and being ready for the next packet transmission if no error is occurred during the step (f).