Method and arrangement in a telecommunication system

• US 10,433,321 B2
• Filed: 02/05/2018
• Issued: 10/01/2019
• Est. Priority Date: 09/19/2008
• Status: Active Grant

• Current Assignee: Telefonaktiebolaget LM Ericsson
• Original Assignee: Telefonaktiebolaget LM Ericsson
• Inventors: Meyer, Michael, Torsner, Johan, Wiemann, Henning, Stattin, Magnus
• Primary Examiner(s): Towfighi, Afshawn M
• Application Number:
  US15/888,393
• Publication Number:
  US 20180160438A1
• Time in Patent Office: 603 Days
• CPC Class Codes: H04L 1/1812 Hybrid protocols; Hybrid automatic repeat request [HARQ]
• CPC Class Codes: H04L 1/1854 Scheduling and prioritising arrangements
• CPC Class Codes: H04L 1/1887 Scheduling and prioritising arrangements
• CPC Class Codes: H04L 5/003 Arrangements for allocating sub-channels of the transmission path
• CPC Class Codes: H04W 72/12 Wireless traffic scheduling
• CPC Class Codes: H04W 72/20 Control channels or signalling for resource management
• CPC Class Codes: H04W 72/23 in the downlink direction of a wireless link, i.e. towards a terminal

Abstract

The present invention relates to a method in a cellular communication system, for avoiding errors in a HARQ process, wherein an NDI flag is used both for indicating either semi-persistent scheduling, SPS activation or SPS retransmissions, and also for indicating, by toggling of the flag, a new transmission in dynamic scheduling mode. The method comprises the steps of receiving, in a scheduling message, an indication that dynamically scheduled transmission will take place; if a semi persistent resource has occurred for the same HARQ process since a previously received indication for dynamically scheduled transmission, then considering the NDI flag to be toggled regardless of the value of the NDI flag. Thus, if the condition is fulfilled, a UE will always regard the NDI flag as indicating or requesting a new data transmission.

Claims

1. A method for processing scheduling information in a cellular communication system, the method comprising:

receiving, at a user equipment (UE), a scheduling message indicating an allocation of transmission resources for a downlink transmission associated with a first Hybrid Automatic Repeat reQuest (HARQ) process of the UE;

determining whether a new data indicator (NDI) flag in the scheduling message has been toggled, wherein determining whether the NDI flag has been toggled comprises considering the NDI flag to have been toggled regardless of a value of the NDI flag if the scheduling message is addressed to an identifier that is associated with dynamic scheduling for the UE and a most recent previous transmission for the first HARQ process occurred on a semi-persistent scheduled resource;

storing the value of the NDI flag; and

receiving either a new data transmission or a retransmission for the first HARQ process in accordance with the determination of whether the NDI flag has been toggled.

2. The method of claim 1, further comprising determining whether the scheduling message is addressed to an identifier that is associated with dynamic scheduling by determining if the scheduling message is addressed to a Cell Radio Network Temporary Identifier (C-RNTI) or a Temporary C-RNTI of the UE.

3. The method of claim 1, wherein receiving either a new data transmission or a retransmission for the first HARQ process in accordance with the determination comprises receiving a first data transmission on the dynamically-scheduled resource, and further comprising, after receiving the first data transmission on the dynamically-scheduled resource, determining whether a second scheduling message received for the dynamically-scheduled transmission resource and associated with the first HARQ process relates to a new transmission or a re-transmission based on whether a value of the NDI flag in the second scheduling message is toggled.

4. The method of claim 3, wherein determining whether the second scheduling message relates to a new transmission or a re-transmission comprises determining whether the NDI flag has been toggled by comparing the stored value of the NDI flag with the current value of the NDI flag.

5. A method for processing scheduling information in a cellular communication system, the method comprising:

receiving, at a user equipment (UE), scheduling messages for dynamically-scheduled downlink transmissions associated with a first Hybrid Automatic Repeat reQuest (HARQ) process of the UE, wherein each of the scheduling messages includes a new data indicator (NDI) flag;

when a most recent previous transmission for the first HARQ process occurred on a dynamically-scheduled resource, determining whether scheduling messages received for the first HARQ process relate to a new transmission or a re-transmission based on whether a respective value of the NDI flag for that scheduling message has been toggled;

when the most recent previous transmission for the first HARQ process occurred on a semi-persistent scheduling (SPS) resource, determining whether scheduling messages received for the first HARQ process relate to a new transmission or a re-transmission regardless of the value of the NDI flag for that scheduling message;

storing the value of the NDI flag; and

receiving either a new transmission or a re-transmission in accordance with each scheduling message.

6. The method of claim 5, wherein receiving scheduling messages for dynamically-scheduled downlink transmissions comprises receiving scheduling messages addressed to a Cell Radio Network Temporary Identifier (C-RNTI) or a Temporary C-RNTI of the UE.

7. The method of claim 5, wherein receiving either a new data transmission or a retransmission in accordance with each scheduling message comprises receiving a first data transmission on the dynamically-scheduled resource;

and further comprising, after receiving the first data transmission on the dynamically-scheduled resource, determining whether a second scheduling message received for the dynamically-scheduled transmission resource and associated with the first HARQ process relates to a new transmission or a re-transmission based on whether a value of the NDI flag in the second scheduling message has been toggled.

8. The method of claim 7, wherein determining whether the second scheduling message relates to a new transmission or a re-transmission based on whether the value of the NDI flag in the second scheduling message has been toggled comprises determining whether the NDI flag has been toggled by comparing the stored value of the NDI flag with the current value of the NDI flag.

9. An apparatus for processing scheduling information in a cellular communication system, the method comprising:

a receiver, at a user equipment (UE), receiving a scheduling message indicating an allocation of transmission resources for a downlink transmission associated with a first Hybrid Automatic Repeat reQuest (HARQ) process of the UE;

a processor determining whether a new data indicator (NDI) flag in the scheduling message has been toggled, wherein determining whether the NDI flag has been toggled comprises considering the NDI flag to have been toggled regardless of a value of the NDI flag if the scheduling message is addressed to an identifier that is associated with dynamic scheduling for the UE and a most recent previous transmission for the first HARQ process occurred on a semi-persistent scheduled resource; and

a memory storing the value of the NDI flag, wherein

either a new data transmission or a retransmission is received for the first HARQ process in accordance with the determination of whether the NDI flag has been toggled.

10. The apparatus of claim 9, wherein the processor further determines whether the scheduling message is addressed to an identifier that is associated with dynamic scheduling by determining if the scheduling message is addressed to a Cell Radio Network Temporary Identifier (C-RNTI) or a Temporary C-RNTI of the UE.

11. The apparatus of claim 9, wherein receiving either a new data transmission or a retransmission for the first HARQ process in accordance with the determination comprises receiving a first data transmission on the dynamically-scheduled resource, and further comprising, after receiving the first data transmission on the dynamically-scheduled resource, determining whether a second scheduling message received for the dynamically-scheduled transmission resource and associated with the first HARQ process relates to a new transmission or a re-transmission based on whether a value of the NDI flag in the second scheduling message is toggled.

12. The apparatus of claim 11 wherein determining whether the second scheduling message relates to a new transmission or a re-transmission comprises determining whether the NDI flag has been toggled by comparing the stored value of the NDI flag with the current value of the NDI flag.

13. An apparatus for processing scheduling information in a cellular communication system, the method comprising:

a receiver, at a user equipment (UE), receiving scheduling messages for dynamically-scheduled downlink transmissions associated with a first Hybrid Automatic Repeat reQuest (HARQ) process of the UE, wherein each of the scheduling messages includes a new data indicator (NDI) flag;

when a most recent previous transmission for the first HARQ process occurred on a dynamically-scheduled resource, a processor configured for determining whether scheduling messages received for the first HARQ process relate to a new transmission or a re-transmission based on whether a respective value of the NDI flag for that scheduling message has been toggled;

when the most recent previous transmission for the first HARQ process occurred on a semi-persistent scheduling (SPS) resource, a processor configured for determining whether scheduling messages received for the first HARQ process relate to a new transmission or a re-transmission regardless of the value of the NDI flag for that scheduling message; and

a memory storing the value of the NDI flag, wherein

either a new transmission or a re-transmission is received in accordance with each scheduling message.

14. The method of claim 13, wherein receiving scheduling messages for dynamically-scheduled downlink transmissions comprises receiving scheduling messages addressed to a Cell Radio Network Temporary Identifier (C-RNTI) or a Temporary C-RNTI of the UE.

15. The method of claim 13, wherein receiving either a new data transmission or a retransmission in accordance with each scheduling message comprises receiving a first data transmission on the dynamically-scheduled resource;

and further comprising, after receiving the first data transmission on the dynamically-scheduled resource, determining whether a second scheduling message received for the dynamically-scheduled transmission resource and associated with the first HARQ process relates to a new transmission or a re-transmission based on whether a value of the NDI flag in the second scheduling message has been toggled.

16. The method of claim 15, wherein determining whether the second scheduling message relates to a new transmission or a re-transmission based on whether the value of the NDI flag in the second scheduling message has been toggled comprises determining whether the NDI flag has been toggled by comparing the stored value of the NDI flag with the current value of the NDI flag.