HARQ systems and methods for grant-free uplink transmissions

Patent metadata

Field	Value
Publication number	US-10868640-B2
Application number	US-201916533994-A
Country	US
Kind code	B2
Filing date	Aug 7, 2019
Priority date	Apr 1, 2016
Publication date	Dec 15, 2020
Grant date	Dec 15, 2020

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 for transmitting uplink data, comprising:
receiving, by a user equipment (UE), a resource configuration for K grant-free uplink transmissions of a data packet, wherein the resource configuration configures K uplink time-frequency resources for the K grant-free uplink transmissions;
performing, by the UE, an initial grant-free transmission of a data packet on one of the K uplink time-frequency resources; and
performing, by the UE, at least one grant-free retransmission of the data packet on at least one uplink time-frequency resource among the K uplink time-frequency resources, until a scheduling grant for a retransmission of the data packet is received before an end of a time domain location of a last uplink time-frequency resource of the K uplink time-frequency resources for the K grant-free uplink transmissions;
in response to receiving the scheduling grant, performing a retransmission of the data packet according to the scheduling grant.

2. The method of claim 1 , wherein a grant-free retransmission is performed without waiting for acknowledgement/negative acknowledgement (ACK/NACK) feedback for a transmission of the data packet.

3. The method of claim 1 , wherein the scheduling grant indicates resources for the retransmission of the data packet.

4. The method of claim 1 , wherein the scheduling grant indicates a modulation and coding scheme (MCS) for the retransmission of the data packet.

5. The method of claim 1 , wherein the scheduling grant indicates a power parameter for the retransmission of the data packet.

6. A user equipment (UE) comprising:
at least one antenna; and
a grant-free transmission module configured to:
receive, via the at least one antenna, a resource configuration for K grant-free uplink transmissions of a data packet, wherein the resource configuration configures K uplink time-frequency resources for the K grant-free uplink transmissions;
perform an initial grant-free transmission of a data packet on one of the K uplink time-frequency resources; and
perform at least one grant-free retransmission of the data packet on at least one uplink time-frequency resource among the K uplink time-frequency resources, until a scheduling grant for a retransmission of the data packet is received before an end of a time domain location of a last uplink time-frequency resource of the K uplink time-frequency resources for the K grant-free uplink transmissions;
in response to receiving the scheduling grant, perform a retransmission of the data packet according to the scheduling grant.

7. The UE of claim 6 , wherein the grant-free transmission module is configured to perform a grant-free retransmission without waiting for acknowledgement/negative acknowledgement (ACK/NACK) feedback for a transmission of the data packet.

8. The UE of claim 6 , wherein the scheduling grant indicates resources for the retransmission of the data packet.

9. The UE of claim 6 , wherein the scheduling grant indicates a modulation and coding scheme (MCS) for the retransmission of the data packet.

10. The UE of claim 6 , wherein the scheduling grant indicates a power parameter for the retransmission of the data packet.

11. A method, comprising:
transmitting, by a base station to a user equipment (UE), a resource configuration for K grant-free uplink transmissions of a data packet, wherein the resource configuration configures K uplink time-frequency resources for the K grant-free uplink transmissions;
receiving, by the base station, an initial grant-free transmission of a data packet on one of the K uplink time-frequency resources; and
receiving, by the base station, at least one grant-free retransmission of the data packet on at least one uplink time-frequency resource among the K uplink time-frequency resources, until a scheduling grant for a retransmission of the data packet is sent by the base station before an end of a time domain location of a last uplink time-frequency resource of the K uplink time-frequency resources for the K grant-free uplink transmissions;
receiving, by the base station, a retransmission of the data packet according to the scheduling grant.

12. The method of claim 11 , wherein a grant-free retransmission is received without the base station transmitting acknowledgement/negative acknowledgement (ACK/NACK) feedback for the data packet.

13. The method of claim 11 , wherein the scheduling grant indicates resources for the retransmission of the data packet.

14. The method of claim 11 , wherein the scheduling grant indicates a modulation and coding scheme (MCS) for the retransmission of the data packet.

15. The method of claim 11 , wherein the scheduling grant indicates a power parameter for the retransmission of the data packet.

16. A base station, comprising:
at least one antenna; and
a grant-free transmission module configured to:
transmit, to a user equipment (UE) via the at least one antenna, a resource configuration for K grant-free uplink transmissions of a data packet, wherein the resource configuration configures K uplink time-frequency resources for the K grant-free uplink transmissions;
receive an initial grant-free transmission of a data packet on one of the K uplink time-frequency resources; and
receive at least one grant-free retransmission of the data packet on at least one uplink time-frequency resource among the K uplink time-frequency resources, until a scheduling grant for a retransmission of the data packet is sent by the base station before an end of a time domain location of a last uplink time-frequency resource of the K uplink time-frequency resources for the K grant-free uplink transmissions;
receive a retransmission of the data packet according to the scheduling grant.

17. The base station of claim 16 , wherein the grant-free transmission module is configured to receive the grant-free retransmission without transmitting acknowledgement/negative acknowledgement (ACK/NACK) feedback for the data packet.

18. The base station of claim 16 , wherein the scheduling grant indicates resources for the retransmission of the data packet.

19. The base station of claim 16 , wherein the scheduling grant indicates a modulation and coding scheme (MCS) for the retransmission of the data packet.

20. The base station of claim 16 , wherein the scheduling grant indicates a power parameter for the retransmission of the data packet.

Assignees

• Cao Yu
• Zhang Liqing
• Huawei Tech Co Ltd

Inventors

• Cao Yu
• Zhang Liqing

Classifications

• 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

• H04L1/1887

  Scheduling and prioritising arrangements · CPC title

• H04L1/1819

  with retransmission of additional or different redundancy · CPC title

• H04L1/1812 Primary

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