Techniques and apparatuses for hybrid automatic repeat request acknowledgement (HARQ-ACK) feedback for carrier aggregation in new radio
Various aspects of the present disclosure generally relate to wireless communication. In some aspects, a user equipment (UE) may determine a first hybrid automatic repeat request acknowledgement (HARQ-ACK) payload for a first component carrier (CC) set based at least in part on a first downlink assignment index (DAI). The UE may determine a second HARQ-ACK payload for a second CC set based at least in part on a second DAI. The UE may transmit the first HARQ-ACK payload for the first CC set and the second HARQ-ACK payload for the second CC set. Numerous other aspects are provided.
1. A method of wireless communication performed by a user equipment (UE), comprising:
determining a first hybrid automatic repeat request acknowledgement (HARQ-ACK) payload of a first size, for a first component carrier (CC) set, based at least on a first downlink assignment index (DAI);
determining a second HARQ-ACK payload of a second size, for a second CC set, based at least on a second DAI, wherein the second size is different from the first size;
transmitting a first size indicator that indicates the first size of the first HARQ-ACK payload and a second size indicator that indicates the second size of the second HARQ-ACK payload; and
transmitting the first HARQ-ACK payload for the first CC set and the second HARQ-ACK payload for the second CC set, wherein the first HARQ-ACK payload is concatenated in a first HARQ-ACK payload group and the second HARQ-ACK payload is concatenated in a second HARQ-ACK payload group.
2. The method of claim 1 , wherein one or more first CCs included in the first CC set are associated with a first code block group (CBG) configuration, and wherein one or more second CCs included in the second CC set are associated with a second CBG configuration that is different from the first CBG configuration.
3. The method of claim 2 , wherein the first CBG configuration is a configuration where CBGs are enabled and the second CBG configuration is a configuration where CBGs are disabled.
4. The method of claim 1 , wherein at least one CC is assigned to the first CC set or the second CC set based at least on a semi-static code block group configuration for the at least one CC.
5. The method of claim 1 , wherein at least one CC is assigned to the first CC set or the second CC set based at least on a dynamic code block group configuration, for the at least one CC, indicated in fallback downlink control information that overrides a default or semi-static code block group configuration.
6. The method of claim 1 , wherein one or more first CCs are assigned to the first CC set and one or more second CCs are assigned to the second CC set for a particular transmission time interval.
7. The method of claim 1 , wherein one or more first CCs are assigned to the first CC set and one or more second CCs are assigned to the second CC based at least on a determination that code block groups are enabled for at least one CC of the UE.
8. The method of claim 1 , wherein the first DAI is a first cumulative DAI and the second DAI is a second cumulative DAI.
9. The method of claim 1 , wherein the first DAI is a first total DAI and the second DAI is a second total DAI.
10. The method of claim 1 , wherein the first HARQ-ACK payload group and the second HARQ-ACK payload group are concatenated with one another for transmission.
11. The method of claim 10 , wherein at least one of the first HARQ-ACK payload group or the second HARQ-ACK payload group is padded with DAI padding prior to concatenation with one another.
12. The method of claim 1 , wherein the first size is one of 2 bits, 8 bits, or 16 bits.
13. The method of claim 1 , where the first size is based on a code block group (CBG) configuration for the first CC set.
14. A user equipment (UE) for wireless communication, comprising:
memory; and
one or more processors, operatively coupled to the memory, configured to:
determine a first hybrid automatic repeat request acknowledgement (HARQ-ACK) payload of a first size, for a first component carrier (CC) set, based at least on a first downlink assignment index (DAI);
determine a second HARQ-ACK payload of a second size, for a second CC set, based at least on a second DAI, wherein the second size is different from the first size;
transmit a first size indicator that indicates the first size of the first HARQ-ACK payload and a second size indicator that indicates the second size of the second HARQ-ACK payload; and
transmit the first HARQ-ACK payload for the first CC set and the second HARQ-ACK payload for the second CC set, wherein the first HARQ-ACK payload is concatenated in a first HARQ-ACK payload group and the second HARQ-ACK payload is concatenated in a second HARQ-ACK payload group.
15. The UE of claim 14 , wherein one or more first CCs included in the first CC set are associated with a first code block group (CBG) configuration, and wherein one or more second CCs included in the second CC set are associated with a second CBG configuration that is different from the first CBG configuration.
16. The UE of claim 15 , wherein the first CBG configuration is a configuration where CBGs are enabled and the second CBG configuration is a configuration where CBGs are disabled.
17. The UE of claim 14 , wherein at least one CC is assigned to the first CC set or the second CC set based at least on at least one of:
a semi-static code block group configuration for the at least one CC,
a dynamic code block group configuration, for the at least one CC, indicated in fallback downlink control information that overrides the semi-static code block group configuration, or
a combination thereof.
18. The UE of claim 14 , wherein one or more first CCs are assigned to the first CC set and one or more second CCs are assigned to the second CC set for a particular transmission time interval.
19. The UE of claim 14 , wherein one or more first CCs are assigned to the first CC set and one or more second CCs are assigned to the second CC set based at least on a determination that code block groups are enabled for at least one CC of the UE.
20. The UE of claim 14 , wherein the first DAI includes at least one of a first cumulative DAI or a first total DAI, and wherein the second DAI includes at least one of a second cumulative DAI or a second total DAI.
21. The UE of claim 14 , wherein the first HARQ-ACK payload group and the second HARQ-ACK payload group are concatenated with one another for transmission.
22. The UE of claim 21 , wherein at least one of the first HARQ-ACK payload group or the second HARQ-ACK payload group is padded with DAI padding prior to concatenation with one another.
23. The UE of claim 14 , wherein the first size is one of 2 bits, 8 bits, or 16 bits.
24. The UE of claim 14 , where the first size is based on a code block group (CBG) configuration for the first CC set.