Harq signaling for grant-free uplink transmissions

Patent metadata

Field	Value
Publication number	US-2018123765-A1
Application number	US-201715799157-A
Country	US
Kind code	A1
Filing date	Oct 31, 2017
Priority date	Nov 3, 2016
Publication date	May 3, 2018
Grant date	—

Abstract

In a wireless communication system, a grant-free uplink transmission is an uplink transmission sent from a user equipment (UE) to a base station that does not need a dynamic and explicit scheduling grant from the base station. Systems and methods are disclosed for performing hybrid automatic repeat request (HARQ) for grant-free uplink transmissions. Signaling relating to the ACK/NACK for the HARQ, as well as signaling relating to configuring the UE for grant-free uplink transmission, is also disclosed.

First claim

1 . A method performed by a base station comprising:
receiving a first grant-free uplink transmission from a first user equipment (UE); receiving a second grant-free uplink transmission from a second UE; transmitting, to the first UE and to the second UE, a group ACK/NACK message indicating an ACK or a NACK corresponding to the first grant-free uplink transmission and an ACK or a NACK corresponding to the second grant-free uplink transmission.

2 . The method of claim 1 , wherein the first UE and the second UE are in a group having a group identifier (ID), wherein the group ACK/NACK is associated with the group ID, and wherein the group ID is a function of grant-free resources at which the first grant-free uplink transmission was sent.

3 . The method of claim 1 , wherein the first UE and the second UE are in a group having a group ID, wherein the group ACK/NACK is associated with the group ID, wherein the group ACK/NACK is transmitted in group-common downlink control information (DCI), and wherein a cyclic redundancy check (CRC) of the group-common DCI is masked by the group ID.

4 . The method of claim 3 , wherein the group ID is a function of at least one of a time unit and frequency location at which the first grant-free uplink transmission was sent.

5 . The method of claim 3 , wherein the group ID is a radio network temporary identifier (RNTI) and is signaled to the first UE in radio resource control (RRC) signaling.

6 . The method of claim 1 , wherein the group ACK/NACK message has a payload that indicates the ACK or NACK, wherein the payload comprises a first bit corresponding to the first grant-free uplink transmission and a second bit corresponding to the second grant-free uplink transmission, wherein each bit indicates whether activity detection was successful or whether data decoding was successful.

7 . The method of claim 6 , wherein a position of the first and second bits in the payload corresponds to at least one of an MA signature and a HARQ process ID of the first and second grant-free uplink transmissions.

8 . The method of claim 6 , wherein a position of the first bit in the payload is signalled to the first UE, using radio resource control (RRC) signaling, prior to the first UE sending the first grant-free uplink transmission.

9 . A base station comprising:
a receiver to receive a first grant-free uplink transmission from a first user equipment (UE), and to receive a second grant-free uplink transmission from a second UE; a grant-free transmission module to generate a group ACK/NACK message that indicates an ACK or a NACK corresponding to the first grant-free uplink transmission and an ACK or a NACK corresponding to the second grant-free uplink transmission.

10 . The base station of claim 9 , wherein the first UE and the second UE are in a group having a group identifier (ID), wherein the group ACK/NACK is associated with the group ID, and wherein the group ID is a function of grant-free resources at which the first grant-free uplink transmission was sent.

11 . The base station of claim 9 , wherein the first UE and the second UE are in a group having a group ID, wherein the group ACK/NACK is associated with the group ID, wherein the base station is to transmit the group ACK/NACK in group-common downlink control information (DCI) and to mask a cyclic redundancy check (CRC) of the group-common DCI by the group ID.

12 . The base station of claim 11 , wherein the group ID is a function of at least one of a time unit and frequency location at which the first grant-free uplink transmission was sent.

13 . The base station of claim 9 , wherein the group ACK/NACK message has a payload that indicates the ACK or NACK, wherein the payload comprises a first bit corresponding to the first grant-free uplink transmission and a second bit corresponding to the second grant-free uplink transmission, wherein each bit indicates whether activity detection was successful or whether data decoding was successful.

14 . The base station of claim 13 , wherein a position of the first and second bits in the payload corresponds to at least one of an MA signature and a HARQ process ID of the first and second grant-free uplink transmissions.

15 . The base station of claim 13 , wherein the base station is to signal, to the first UE, a position of the first bit in the payload, using radio resource control (RRC) signaling, prior to the first UE sending the first grant-free uplink transmission.

16 . A method performed by a first user equipment (UE) comprising:
transmitting a first grant-free uplink transmission to a base station; receiving a group ACK/NACK message indicating an ACK or a NACK corresponding to the first grant-free uplink transmission and an ACK or a NACK corresponding to a second grant-free uplink transmission from a second UE.

17 . The method of claim 16 , wherein the first UE and the second UE are in a group having a group identifier (ID), wherein the group ACK/NACK is associated with the group ID, and wherein the group ID is a function of grant-free resources at which the first grant-free uplink transmission is sent.

18 . The method of claim 16 , wherein the first UE and the second UE are in a group having a group ID, wherein the group ACK/NACK is associated with the group ID, wherein the group ACK/NACK is received in group-common downlink control information (DCI), and wherein a cyclic redundancy check (CRC) of the group-common DCI is masked by the group ID.

19 . The method of claim 18 , wherein the group ID is a function of at least one of a time unit and frequency location at which the first grant-free uplink transmission is sent.

20 . The method of claim 18 , wherein the group ID is a radio network temporary identifier (RNTI) and is signaled to the first UE in radio resource control (RRC) signaling.

21 . The method of claim 16 , wherein the group ACK/NACK message has a payload that indicates the ACK or NACK, wherein the payload comprises a first bit corresponding to the first grant-free uplink transmission and a second bit corresponding to the second grant-free uplink transmission, wherein each bit indicates whether activity detection was successful or whether data decoding was successful.

22 . The method of claim 21 , wherein a position of the first and second bits in the payload corresponds to at least one of an MA signature and a HARQ process ID of the first and second grant-free uplink transmissions.

23 . The method of claim 21 , wherein a position of the first bit in the payload is signalled to the first UE, using radio resource control (RRC) signaling, prior to the first UE sending the first grant-free uplink transmission.

24 . A first user equipment (UE) comprising:
a transmitter to transmit a first grant-free uplink transmission to a base station; a receiver to receive a group ACK/NACK message that indicates an ACK or a NACK corresponding to the first grant-free uplink transmission and an ACK or a NACK corresponding to a second grant-free uplink transmission from a second UE.

25 . The first UE of claim 24 , wherein the first UE and the second UE are in a group having a group identifier (ID), wherein the group ACK/NACK is associated with the group ID, and wherein the group ID is a function of grant-free resources at which the first grant-free uplink transmission is sent.

26 . The first UE of claim 24 , wherein the first UE and the second UE are in a group ha

Assignees

• Cao Yu
• Zhang Liqing
• Ma Jianglei
• Huawei Tech Co Ltd

Inventors

• Cao Yu
• Zhang Liqing
• Ma Jianglei

Classifications

• H04W72/21

  in the uplink direction of a wireless link, i.e. towards the network · CPC title

• H04L1/1614 Primary

  using bitmaps · CPC title

• H04L1/1819 Primary

  with retransmission of additional or different redundancy · CPC title

• H04L5/0048

  Allocation of pilot signals, i.e. of signals known to the receiver (allocation of control signalling H04L5/0053; use of control signalling H04L5/0091) · CPC title

• H04L5/0055 Primary

  Physical resource allocation for ACK/NACK (for physical mapping arrangements in ARQ protocols H04L1/1861) · CPC title