Scheduling of multiple transport blocks for grant-free uplink transmission
Various aspects of the present disclosure generally relate to wireless communication. In some aspects, a user equipment may receive configuration information that indicates a maximum number of transport blocks permitted to be transmitted in one or more transmission occasions in a transmission period of a configured grant for an uplink (UL) transmission; transmit, based at least in part on a set of transport blocks to be transmitted in the transmission period including fewer transport blocks than the maximum number of transport blocks, an indication to suppress communication of one or more remaining transport blocks of the transmission period other than the set of transport blocks; and perform the UL transmission of the set of transport blocks in the transmission period based at least in part on the configuration information. Numerous other aspects are provided.
1 . A method of wireless communication performed by a user equipment (UE), comprising:
receiving radio resource control (RRC) configuration information that indicates a resource allocation of a maximum number of transport blocks permitted to be transmitted in one or more transmission occasions in a transmission period corresponding to a grant-free uplink (UL) transmission;
transmitting, based at least in part on a set of transport blocks to be transmitted in the transmission period including fewer transport blocks than the maximum number of transport blocks, an indication that one or more remaining transport blocks of the transmission period, other than the set of transport blocks, are not to be transmitted from the UE, wherein the indication is a one-bit indication in one or more starting symbols of the set of transport blocks, and the indication comprises a front-loaded demodulation reference signal (DMRS), and wherein a DMRS pattern of the DMRS indicates that the one or more remaining transport blocks are not to be transmitted in the transmission period after a transport block associated with the front-loaded DMRS; and
performing the grant-free UL transmission of the set of transport blocks in the transmission period in accordance with the indication and based at least in part on the configuration information.
2 . The method of claim 1 ,
wherein the one or more transmission occasions include a non-continuous group of slots or a non-continuous group of mini-slots.
3 . The method of claim 2 ,
wherein a time gap between two transmission occasions is based at least in part on a processing time for receiving the indication.
4 . The method of claim 1 ,
wherein the DMRS pattern includes at least one of:
a DMRS sequence,
a cyclic shift, or
a transmission comb value.
5 . The method of claim 1 ,
wherein transmitting the indication comprises:
encoding the indication and the set of transport blocks using different encoding schemes; and
mapping the indication and the set of transport blocks to different resource elements.
6 . The method of claim 1 ,
wherein respective hybrid automatic repeat request (HARQ) process numbers of the set of transport blocks are continuous.
7 . The method of claim 6 ,
wherein a starting HARQ process number of the set of transport blocks is determined based at least in part on one or more of:
a periodicity of the one or more transmission occasions,
the maximum number of transport blocks, or
an absolute time index of the transmission.
8 . The method of claim 7 ,
wherein the starting HARQ process number is based at least in part on an actual number of transport blocks included in the set of transport blocks.
9 . The method of claim 1 , further comprising:
performing a retransmission of the set of transport blocks based at least in part on an uplink grant, wherein the uplink grant includes a code block group (CBG) transmission information field.
10 . The method of claim 9 ,
wherein the retransmission of the set of transport blocks is based at least in part on a CBG based configuration, wherein each bit in the CBG transmission information field indicates a respective subset of transport blocks for retransmission.
11 . The method of claim 9 , wherein, when a CBG based configuration is not supported by the UE, the uplink grant comprises downlink control information for retransmission of a single transport block of the set of transport blocks.
12 . The method of claim 1 ,
wherein the indication is transmitted in an earliest available resource after determining that the set of transport blocks includes fewer transport blocks than the maximum number of transport blocks.
13 . The method of claim 1 ,
wherein the UE is permitted to transmit fewer than the maximum number of transport blocks.
14 . The method of claim 1 ,
wherein the indication identifies the one or more remaining transport blocks or the set of transport blocks.
15 . A method of wireless communication performed by a base station, comprising:
transmitting, to a user equipment (UE), radio resource control (RRC) configuration information that indicates a resource allocation of a maximum number of transport blocks permitted to be transmitted in one or more transmission occasions in a transmission period corresponding to a grant-free uplink (UL) transmission;
receiving an indication that one or more remaining transport blocks of the transmission period, other than a set of transport blocks, are not to be transmitted from the UE, wherein the set of transport blocks includes fewer transport blocks than the maximum number of transport blocks, wherein the indication is a one-bit indication in one or more starting symbols of the set of transport blocks, and the indication comprises a front-loaded demodulation reference signal (DMRS), and wherein a DMRS pattern of the DMRS indicates that the one or more remaining transport blocks are not to be transmitted in the transmission period after a transport block associated with the front-loaded DMRS; and
receiving the grant-free UL transmission of the set of transport blocks in the transmission period in accordance with the indication.
16 . The method of claim 15 ,
wherein the one or more transmission occasions include a non-continuous group of slots or a non-continuous group of mini-slots, and wherein a time gap between two transmission occasions is based at least in part on a processing time of the base station for receiving the indication.
17 . The method of claim 15 ,
wherein the indication is encoded with the set of transport blocks using different encoding schemes and wherein the indication and the set of transport blocks are mapped to different resource elements.
18 . The method of claim 17 ,
wherein respective hybrid automatic repeat request (HARQ) process numbers of the set of transport blocks are continuous, and wherein a starting HARQ process number of the set of transport blocks is determined based at least in part on one or more of:
a periodicity of the one or more transmission occasions,
the maximum number of transport blocks, or
an absolute time index of the transmission.
19 . The method of claim 15 , further comprising:
transmitting an uplink grant that includes a code block group (CBG) transmission information field; and
receiving a retransmission of the set of transport blocks based at least in part on the uplink grant.
20 . The method of claim 19 ,
wherein the retransmission of the set of transport blocks is based at least in part on a CBG based configuration, wherein each bit in the CBG transmission information field indicates a respective subset of transport blocks for retransmission.
21 . The method of claim 19 , wherein, when a CBG based configuration is not supported by the UE, the uplink grant comprises downlink control information for retransmission of a single transport block of the set of transport blocks.
22 . A user equipment (UE) for wireless communication, comprising:
one or more memories; and
one or more processors, coupled to the one or more memories, which are configured, individually or in any combination, to:
receive radio resource control (RRC) configuration information that indicates a resource allocation of a maximum number of transport blocks permitted to be transmitted in one or more transmission occasions in a transmission period corresponding to a grant-free uplink (UL) transmission;
transmit, based at least in part on a set of transport blocks to be transmitted in the transmission period including fewer transport blocks than the maximum number of transport blocks, an indication that one or more remaining transport blocks of the transmission period, other than the set of transport blocks, are not to be transmitted from the UE, wherein the indication is a one-bit indication in one or more starting symbols of the set of transport blocks, and the indication comprises a front-loaded demodulation reference signal (DMRS), and wherein a DMRS pattern of the DMRS indicates that the one or more remaining transport blocks are not to be transmitted in the transmission period after a transport block associated with the front-loaded DMRS; and
perform the grant-free UL transmission of the set of transport blocks in the transmission period in accordance with the indication and based at least in part on the configuration information.
23 . A base station for wireless communication, comprising:
one or more memories; and
one or more processors, coupled to the one or more memories, which are configured, individually or in any combination, to:
transmit, to a user equipment (UE), radio resource control (RRC) configuration information that indicates a resource allocation of a maximum number of transport blocks permitted to be transmitted in one or more transmission occasions in a transmission period corresponding to a grant-free uplink (UL) transmission;
receive an indication that one or more remaining transport blocks of the transmission period, other than a set of transport blocks, are not to be transmitted from the UE, wherein the set of transport blocks includes fewer transport blocks than the maximum number of transport blocks, wherein the indication is a one-bit indication in one or more starting symbols of the set of transport blocks, and the indication comprises a front-loaded demodulation reference signal (DMRS), and wherein a DMRS pattern of the DMRS indicates that the one or more remaining transport blocks are not to be transmitted in the transmission period after a transport block associated with the front-loaded DMRS; and
receive the grant-free UL transmission of the set of transport blocks in the transmission period in accordance with the indication.
24 . The method of claim 1 , further comprising:
receiving physical downlink control channel (PDCCH) communication indicating a second maximum number of transport blocks, wherein the second maximum number of transport block is less than the maximum number of transport blocks.