HARQ systems and methods for grant-free uplink transmissions

Patent metadata

Field	Value
Publication number	US-10382169-B2
Application number	US-201715470455-A
Country	US
Kind code	B2
Filing date	Mar 27, 2017
Priority date	Apr 1, 2016
Publication date	Aug 13, 2019
Grant date	Aug 13, 2019

Abstract

Systems and methods are disclosed for performing hybrid automatic repeat request (HARQ) for grant-free uplink transmissions. Some of the systems and methods disclosed herein may address problems such as how to perform acknowledgement (ACK) and/or negative acknowledgement (NACK), how to determine and signal retransmission timing, how to determine the transmission/retransmission attempt and the redundancy version (RV), and/or how to perform the HARQ combining.

First claim

The invention claimed is:

1. A method performed by a user equipment (UE) comprising:
transmitting an initial grant-free uplink transmission of encoded data;
without receiving a negative acknowledgement (NACK) for the encoded data, addressed to the UE, transmitting at least one grant-free uplink retransmission of the encoded data;
wherein the initial grant-free uplink transmission utilizes a first multiple access (MA) signature, and a grant-free uplink retransmission of the encoded data utilizes a second MA signature and carries retransmission data for facilitating decoding of the encoded data.

2. The method of claim 1 , wherein the first MA signature comprises a first reference signal.

3. The method of claim 1 , wherein the second MA signature comprises a second reference signal.

4. The method of claim 1 , wherein the first and second MA signatures are different from one another.

5. The method of claim 1 , wherein the first MA signature and the second MA signature are selected from a pre-defined tuple of MA signatures.

6. The method of claim 1 , wherein the first MA signature indicates a redundancy version (RV) of the encoded data in the initial grant-free uplink transmission.

7. The method of claim 1 , wherein the second MA signature indicates a redundancy version (RV) of the encoded data in the grant-free uplink retransmission.

8. The method of claim 1 , wherein the initial grant-free uplink transmission is transmitted on a first uplink resource and the grant-free uplink retransmission is transmitted on a second uplink resource, wherein the second uplink resource is different from the first uplink resource.

9. The method of claim 8 , wherein the UE selects the first and second uplink resources based on a pre-defined resource hopping pattern.

10. The method of claim 1 , further comprising transmitting grant-free uplink retransmissions until receiving an acknowledgement (ACK) addressed to the UE.

11. The method of claim 10 , wherein the ACK is received on a downlink acknowledgement channel.

12. The method of claim 1 , further comprising:
without receiving the NACK addressed to the UE, transmitting the at least one grant-free uplink retransmission of the encoded data until an acknowledgement (ACK) is received or until a number of grant-free uplink retransmissions reaches a predetermined value.

13. The method of claim 1 , further comprising:
without receiving the NACK addressed to the UE, transmitting k grant-free uplink retransmissions of the encoded data.

14. The method of claim 1 , wherein at least one of the first MA signature and an uplink resource identifies the initial grant-free uplink transmission as the initial transmission of the encoded data.

15. A method performed by a user equipment (UE) comprising:
transmitting an initial grant-free uplink transmission of encoded data;
without receiving a negative acknowledgement (NACK) for the encoded data, addressed to the UE, transmitting at least one grant-free uplink retransmission of the encoded data;

wherein a grant-free uplink transmission from the UE utilizes at least one of a multiple access (M A) signature and an uplink resource that identifies a redundancy version (RV) of the encoded data in the grant-free uplink transmission.

16. The method of claim 1 , wherein transmitting the at least one grant-free uplink retransmission of the encoded data occurs without waiting for receipt of the NACK.

17. A user equipment (UE) comprising:
at least one antenna; and
a grant-free transmission module;
the at least one antenna configured to transmit an initial grant-free uplink transmission of encoded data;
the grant-free transmission module configured to, without receiving a negative acknowledgement (NACK) addressed to the UE for the encoded data, cause the UE to transmit at least one grant-free uplink retransmission of the encoded data;

wherein the initial grant-free uplink transmission utilizes a first multiple access (MA) signature, and a grant-free uplink retransmission of the encoded data utilizes a second MA signature and carries retransmission data for facilitating successful decoding of the encoded data.

18. The UE of claim 17 , wherein the first MA signature comprises a first reference signal.

19. The UE of claim 17 , wherein the second MA signature comprises a second reference signal.

20. The UE of claim 17 , wherein the first and second MA signatures are different from one another.

21. The UE of claim 17 , wherein the first MA signature and the second MA signature are selected from a pre-defined tuple of MA signatures.

22. The UE of claim 17 , wherein the first MA signature indicates a a redundancy version (RV) of the encoded data in the initial grant-free uplink transmission.

23. The UE of claim 17 , wherein the second MA signature indicates an a redundancy version (RV) of the encoded data in the grant-free uplink retransmission.

24. The UE of claim 17 , wherein the initial grant-free uplink transmission is transmitted on a first uplink resource and the grant-free uplink retransmission is transmitted on a second uplink resource, wherein the second uplink resource is different from the first uplink resource.

25. The UE of claim 24 , wherein the grant-free transmission module is configured to select the first and second uplink resources based on a pre-defined resource hopping pattern.

26. The UE of claim 17 , wherein the grant-free transmission module is configured to cause the UE to transmit grant-free uplink retransmissions until receiving an acknowledgement (ACK) addressed to the UE.

27. The UE of claim 26 , wherein the ACK is received on a downlink acknowledgement channel.

28. The UE of claim 17 , wherein the grant-free transmission module is further configured to:
without receiving the NACK addressed to the UE, cause the UE to transmit the at least one grant-free uplink retransmission of the encoded data until an acknowledgement (ACK) is received or until a number of grant-free uplink retransmissions reaches a predetermined value.

29. The UE of claim 17 , wherein the grant-free transmission module is further configured to:
without receiving the NACK addressed to the UE, cause the UE to transmit k grant-free uplink retransmissions of the encoded data.

30. The UE of claim 17 , wherein at least one of the first MA signature and an uplink resource identifies the initial grant-free uplink transmission as the initial transmission of the encoded data.

31. A user equipment (UE) comprising:
at least one antenna; and
a grant-free transmission module;
the at least one antenna configured to transmit an initial grant-free uplink transmission of encoded data;
the grant-free transmission module configured to, without receiving a negative acknowledgement (NACK) addressed to the UE for the encoded data, cause the UE to transmit at least one grant-free uplink retransmission of the encoded data,

wherein a grant-free uplink transmission from the UE utilizes at least one of a multiple access (MA) signature and an uplink resource that identifies a redundancy version (RV) of the encoded data in the grant-free uplink transmission.

32. The UE of claim 17 , wherein the grant-free transmission module is further configured to: transmit the at least one grant-free uplink retransmission of the encoded data

Assignees

• Cao Yu
• Zhang Liqing
• Huawei Tech Co Ltd

Inventors

• Cao Yu
• Zhang Liqing

Classifications

• H04L1/1887

  Scheduling and prioritising arrangements · CPC title

• H04L1/0079 Primary

  Formats for control data (H04L1/16 takes precedence; training sequences H04L25/00 and H04L27/00) · CPC title

• H04L1/1845

  Combining techniques, e.g. code combining · CPC title

• H04L1/1812 Primary

  Hybrid protocols; Hybrid automatic repeat request [HARQ] · CPC title

• H04L1/1819

  with retransmission of additional or different redundancy · CPC title