Selection from multiple transport blocks in uplink configuration grant (UL-CG) based on uplink buffer data
A method of wireless communication by a user equipment (UE) includes receiving a configured grant for an uplink transmission occasion including a number of transport blocks (TBs). The configured grant indicates a first modulation and coding scheme (MCS) and a first quantity of layers for a first of the TBs, and a second MCS and a second quantity of layers for a second of the TBs. The method also includes selecting the first TB and/or the second TB for an uplink transmission based on an amount of data stored in an uplink buffer. The method further includes transmitting the data in the first TB and/or the second TB that was selected.
1. A method of wireless communication by a user equipment (UE), comprising:
receiving a configured grant for an uplink transmission occasion including a plurality of transport blocks (TBs), the configured grant indicating a first modulation and coding scheme (MCS) and a first quantity of layers for a first TB of the plurality of TBs, and a second MCS and a second quantity of layers for a second TB of the plurality of TBs;
selecting at least one of the first TB or the second TB, from the plurality of TBs, for an uplink transmission based on an amount of data stored in an uplink buffer;
selecting the first TB associated with the first MCS when the amount of data in the uplink buffer exceeds a first threshold indicating enough data to transmit on the first TB associated with the first MCS, but is less than a second threshold indicating not enough data to transmit on the plurality of TBs, the first MCS being higher than the second MCS;
selecting the second TB associated with the second MCS when the amount of data in the uplink buffer exceeds a third threshold indicating enough data to transmit on the second TB associated with the second MCS but is less than a fourth threshold indicating not enough data to transmit on the first TB with the first MCS;
transmitting the data in the at least one the first TB or the second TB that was selected; and
skipping transmission during the transmission occasion when the uplink buffer does not contain enough data to transmit on the second TB with the second MCS.
2. The method of claim 1 , further comprising receiving a configuration indicating a TB to select when the uplink buffer does not contain enough data to transmit on the plurality of TBs.
3. The method of claim 1 , further comprising repeating transmission on layers of the second TB of the plurality of TBs in response to selecting the first TB of the plurality of TBs for uplink transmission, the first TB and the second TB having a same quantity of layers.
4. The method of claim 1 , further comprising repeating transmission of the data a plurality of times on layers of the second TB of the plurality of TBs in response to selecting the first TB of the plurality of TBs for uplink transmission, the first TB having a smaller quantity of layers than the second TB.
5. The method of claim 1 , further comprising transmitting information related to the data transmitted on the first TB of the plurality of TBs selected for the uplink transmission, the information being transmitted on layers of the second TB of the plurality of TBs, the first TB having a larger quantity of layers than the second TB.
6. The method of claim 5 , in which the information related to the data comprises additional parity bits for the data.
7. The method of claim 5 , in which the information related to the data comprises selected layers for the data.
8. The method of claim 1 , further comprising remapping layers for transmitting data on the first TB to include layers of the second TB of the plurality of TBs in response to the first TB having a larger quantity of layers than the second TB.
9. The method of claim 1 , further comprising indicating to a network whether the UE is transmitting on the first TB or the plurality of TBs.
10. The method of claim 9 , in which the indicating is implicit based on a dedicated demodulation reference signal (DMRS) sequence.
11. The method of claim 9 , in which the indicating is via uplink control information (UCI).
12. The method of claim 9 , in which the indicating is via a payload of a most recent physical uplink shared channel (PUSCH) transmitted before the uplink transmission occasion.
13. An apparatus for wireless communication by a user equipment (UE), comprising:
a memory; and
at least one processor coupled to the memory, the at least one processor configured:
to receive a configured grant for an uplink transmission occasion including a plurality of transport blocks (TBs), the configured grant indicating a first modulation and coding scheme (MCS) and a first quantity of layers for a first TB of the plurality of TBs, and a second MCS and a second quantity of layers for a second TB of the plurality of TBs;
to select at least one of the first TB or the second TB, from the plurality of TBs, for an uplink transmission based on an amount of data stored in an uplink buffer;
to select the first TB associated with the first MCS when the amount of data in the uplink buffer exceeds a first threshold indicating enough data to transmit on the first TB associated with the first MCS, but is less than a second threshold indicating not enough data to transmit on the plurality of TBs, the first MCS being higher than the second MCS;
to select the second TB associated with the second MCS when the amount of data in the uplink buffer exceeds a third threshold indicating enough data to transmit on the second TB associated with the second MCS but is less than a fourth threshold indicating not enough data to transmit on the first TB with the first MCS;
to transmit the data in the at least one the first TB or the second TB that was selected; and
to skip transmission during the transmission occasion when the uplink buffer does not contain enough data to transmit on the second TB with the second MCS.
14. The apparatus of claim 13 , in which the at least one processor is further configured to indicate a TB to select when the uplink buffer does not contain enough data to transmit on the plurality of TBs.
15. The apparatus of claim 13 , in which the at least one processor is further configured to repeat transmission on layers of the second TB of the plurality of TBs in response to selecting the first TB of the plurality of TBs for uplink transmission, the first TB and the second TB having a same quantity of layers.
16. The apparatus of claim 13 , in which the at least one processor is further configured to repeat transmission of the data a plurality of times on layers of the second TB of the plurality of TBs in response to selecting the first TB of the plurality of TBs for uplink transmission, the first TB having a smaller quantity of layers than the second TB.
17. The apparatus of claim 13 , in which the at least one processor is further configured to transmit information related to the data transmitted on the first TB of the plurality of TBs selected for the uplink transmission, the information being transmitted on layers of the second TB of the plurality of TBs, the first TB having a larger quantity of layers than the second TB.
18. The apparatus of claim 17 , in which the information related to the data comprises additional parity bits for the data.
19. The apparatus of claim 17 , in which the information related to the data comprises selected layers for the data.
20. The apparatus of claim 13 , in which the at least one processor is further configured to transmit data on the first TB to include layers of the second TB of the plurality of TBs in response to the first TB having a larger quantity of layers than the second TB.
21. The apparatus of claim 13 , in which the at least one processor is further configured to indicate to a network whether the UE is transmitting on the first TB or the plurality of TBs.
22. The apparatus of claim 21 , in which the at least one processor indicates implicitly based on a dedicated demodulation reference signal (DMRS) sequence.
23. The apparatus of claim 21 , in which the at least one processor indicates via uplink control information (UCI).
24. The apparatus of claim 21 , in which the at least one processor indicates to the network via a payload of a most recent physical uplink shared channel (PUSCH) transmitted before the uplink transmission occasion.