Method for reducing delay in a communication system employing HARQ

• US 8,325,650 B2
• Filed: 11/01/2006
• Issued: 12/04/2012
• Est. Priority Date: 11/01/2006
• Status: Active Grant

• Current Assignee: Optis Cellular Technology LLC (Brevet Capital)
• Original Assignee: Telefonaktiebolaget LM Ericsson
• Inventors: Hu, Rong, Wang, Hai
• Primary Examiner(s): SCHEIBEL, ROBERT C
• Application Number:
  US12/447,844
• Publication Number:
  US 20100067460A1
• Time in Patent Office: 2,225 Days
• Field of Search: None
• US Class Current: 370/328
• CPC Class Codes: H04L 1/1607 Details of the supervisory signal
• CPC Class Codes: H04L 1/1812 Hybrid protocols; Hybrid automatic repeat request [HARQ]
• CPC Class Codes: H04L 1/1845 Combining techniques, e.g. code combining

Abstract

The invention relates to a method and an arrangement for reducing transmission delay on a radio interface in a communication network, comprising a communication network node (15) transmitting packet data to one or more user equipments (18) over said radio interface. A number of transmission attempts needed for transmitting said packet data estimating, based on which a number of re-transmissions of said first packet data to perform is determined. The determined number of re-transmission is proactively transmitted before an ACK or NACK message is received from the user equipments.

Claims

1. A method of reducing transmission delay on downlink channels over a radio interface in a communication network, comprising a communication network node transmitting packet data to one or more user equipments over said radio interface, the method comprising:

estimating a number of transmission attempts needed for transmitting said packet data based on a ratio of the signal-to-interference ratio that is required to meet the certain quality-of-service requirement and a signal-to-interference ratio that is achievable;

transmitting a first packet data; and

re-transmitting said first packet data said estimated number of transmission attempts without waiting for a feedback message from a user equipment between each re-transmission of said first packet data.

2. A method according to claim 1, where the method further comprises:

continuing retransmission of said first packet data until the earlier of reaching said estimated number of transmission attempts or receiving a feedback message containing an acknowledgement from the user equipment for said first transmitted packet data.

3. A method according to claim 2, where the method further comprises:

continuing retransmission of said first packet data in response to receiving a feedback message containing a negative acknowledgement from the user equipment for said first transmitted packet data.

4. A communication network node arranged to transmit packet data to one or more receivers on downlink channels over a radio interface in a communication network and to reduce transmission delay on said radio interface, where said communication network node comprising:

circuitry that is configured to;

estimate a number of transmission attempts needed for transmitting said packet data based on a ratio of the signal-to-interference ratio that is required to meet the certain quality-of-service requirement and a signal-to-interference ratio that is achievable;

transmit a first packet data; and

re-transmit said first packet data said estimated number of transmission attempts without waiting for a feedback message from a user equipment between each re-transmission of said first packet data.

5. A communication network node according to claim 4, where the communication network node further comprising:

circuitry that is configured to;

interrupt said re-transmissions in response to receiving a feedback message containing an acknowledgement from the user equipment for said first transmitted packet data.

6. A communication network node according to claim 4, where the communication network node further comprising:

circuitry that is further configured to;

continue retransmission of said first packet data until said estimated number of transmission attempts is reached, in response to the receiver block receiving the feedback message containing a negative acknowledgement from the user equipment for said first transmitted packet data.

7. A communication network node according to claim 4, where the communication network node is a radio base station.

8. A non-transitory computer-readable medium containing a computer program for reducing transmission delay on downlink channels over a radio interface in a communication network, comprising a communication network node transmitting packet data to one or more user equipments over said radio interface, where the computer program, when executed by a processor, cause the processor to perform a method comprising:

estimating a number of transmission attempts needed for transmitting said packet data based on a ratio of the signal-to-interference ratio that is required to meet the certain quality-of-service requirement and a signal-to-interference ratio that is achievable;

transmitting a first packet data;

re-transmitting said first packet data said estimated number of transmission attempts without waiting for a feedback message from a user equipment between each re-transmission of said first packet data.