Code block grouping and feedback that support efficient retransmissions
Methods, systems, and devices for wireless communication are described. A wireless device may transmit feedback, such as hybrid automatic repeat request (HARD) feedback for groups of code blocks rather than for an entire transport block or individual code blocks. The wireless device may transmit an acknowledgement (ACK) or negative-acknowledgement (NACK) to provide feedback for each code block group of a set of code block groups. An ACK may indicate that code blocks in a code block group were successfully decoded, and a NACK may indicate that at least one code block in a code block group was not successfully decoded. Wireless devices may support several techniques for grouping code blocks for feedback reporting to allow for efficient retransmissions and limited overhead. Different grouping schemes may be employed depending on system constraints, device capability, link conditions, or the like.
1. A method for wireless communication, comprising:
receiving a transport block that comprises a plurality of code blocks;
receiving an indication to group code blocks of the plurality of code blocks of the transport block for feedback reporting, wherein:
a first set of code blocks of the plurality of code blocks are grouped into one or more code block groups comprising a first quantity of code blocks,
the one or more code block groups of the first quantity of code blocks comprise a first plurality of code block groups of the first quantity of code blocks,
a second set of code blocks of the plurality of code blocks are grouped into one or more code block groups comprising a second quantity of code blocks,
the one or more code block groups of the second quantity of code blocks comprise a second plurality of code block groups of the second quantity of code blocks,
the first quantity of code blocks is different from the second quantity of code blocks, and
each code block group comprises a distinct subset of code blocks of the plurality of code blocks and each code block group of the one or more code block groups comprising the first quantity of code blocks comprises a same number of code blocks; and
transmitting an acknowledgement or negative-acknowledgement for each code block group based at least in part on the indication.
2. The method of claim 1 , wherein:
the acknowledgement indicates that code blocks within a code block group were successfully decoded; and
the negative-acknowledgement indicates that at least one code block in a code block group was not successfully decoded.
3. The method of claim 1 , further comprising:
receiving an indication of a number of code block groups to be formed, wherein code blocks of the plurality of code blocks are grouped based at least in part on the indication of the number of code block groups to be formed.
4. The method of claim 1 , wherein adjacent sets of two or more code blocks of the plurality of code blocks are within a same code block group.
5. The method of claim 4 , wherein the adjacent sets of two or more code blocks of the plurality of code blocks are adjacent in a time domain or a frequency domain.
6. The method of claim 1 , wherein a code block group comprises multiple code block groups.
7. The method of claim 1 , further comprising:
identifying a grouping of the code blocks of the plurality of code blocks based at least in part on a type of service associated with the transport block, or a modulation and coding scheme (MCS) used to transmit the transport block, or any combination thereof.
8. The method of claim 1 , wherein the second set of code blocks comprises a remaining set of code blocks that are distributed to one code block group comprising the second quantity of code blocks.
9. The method of claim 1 , wherein at least one of the code blocks of the plurality of code blocks is included in two or more code block groups of a plurality of code block groups.
10. The method of claim 1 , wherein the plurality of code blocks are grouped into a first plurality of code block groups and a second plurality of code block groups, wherein each code block group of the second plurality of code block groups comprises a code block from each of the first plurality of code block groups.
11. The method of claim 1 , wherein each code block of the plurality of code blocks is distributed to a different combination of code block groups.
12. An apparatus for wireless communication, comprising:
a processor; and
memory coupled with the processor, with instructions stored in the memory, the instructions being executable by the processor to cause the apparatus to:
receive a transport block that comprises a plurality of code blocks;
receive an indication to group code blocks of the plurality of code blocks of the transport block for feedback reporting, wherein:
a first set of code blocks of the plurality of code blocks are grouped into one or more code block groups comprising a first quantity of code blocks,
the one or more code block groups of the first quantity of code blocks comprise a first plurality of code block groups of the first quantity of code blocks,
a second set of code blocks of the plurality of code blocks are grouped into one or more code block groups comprising a second quantity of code blocks,
the one or more code block groups of the second quantity of code blocks comprise a second plurality of code block groups of the second quantity of code blocks,
the first quantity of code blocks is different from the second quantity of code blocks, and
each code block group comprises a distinct subset of code blocks of the plurality of code blocks and each code block group of the one or more code block groups comprising the first quantity of code blocks comprises a same number of code blocks; and
transmit an acknowledgement or negative-acknowledgement for each code block group based at least in part on the indication.
13. The apparatus of claim 12 , wherein:
the acknowledgement indicates that code blocks within a code block group were successfully decoded; and
the negative-acknowledgement indicates that at least one code block in a code block group was not successfully decoded.
14. The apparatus of claim 12 , wherein the instructions are further executable by the processor to cause the apparatus to:
receive an indication of a number of code block groups to be formed, wherein code blocks of the plurality of code blocks are grouped based at least in part on the indication of the number of code block groups to be formed.
15. The apparatus of claim 12 , wherein adjacent sets of two or more code blocks of the plurality of code blocks are within a same code block group.
16. The apparatus of claim 15 , wherein the adjacent sets of two or more code blocks of the plurality of code blocks are adjacent in a time domain or a frequency domain.
17. The apparatus of claim 12 , wherein a code block group comprises multiple code block groups.
18. The apparatus of claim 12 , wherein the instructions are further executable by the processor to cause the apparatus to:
identify a grouping of the code blocks of the plurality of code blocks based at least in part on a type of service associated with the transport block, or a modulation and coding scheme (MCS) used to transmit the transport block, or any combination thereof.
19. The apparatus of claim 12 , wherein the second set of code blocks comprises a remaining set of code blocks that are distributed to one code block group comprising the second quantity of code blocks.
20. The apparatus of claim 12 , wherein at least one of the code blocks of the plurality of code blocks is included in two or more code block groups of a plurality of code block groups.
21. The apparatus of claim 12 , wherein the plurality of code blocks are grouped into a first plurality of code block groups and a second plurality of code block groups, wherein each code block group of the second plurality of code block groups comprises a code block from each of the first plurality of code block groups.
22. The apparatus of claim 12 , wherein each code block of the plurality of code blocks is distributed to a different combination of code block groups.
23. An apparatus for wireless communication, comprising:
means for receiving a transport block that comprises a plurality of code blocks;
means for receiving an indication to group code blocks of the plurality of code blocks of the transport block for feedback reporting, wherein:
a first set of code blocks of the plurality of code blocks are grouped into one or more code block groups comprising a first quantity of code blocks,
the one or more code block groups of the first quantity of code blocks comprise a first plurality of code block groups of the first quantity of code blocks,
a second set of code blocks of the plurality of code blocks are grouped into one or more code block groups comprising a second quantity of code blocks,
the one or more code block groups of the second quantity of code blocks comprise a second plurality of code block groups of the second quantity of code blocks,
the first quantity of code blocks is different from the second quantity of code blocks, and
each code block group comprises a distinct subset of code blocks of the plurality of code blocks and each code block group of the one or more code block groups comprising the first quantity of code blocks comprises a same number of code blocks; and
means for transmitting an acknowledgement or negative-acknowledgement for each code block group based at least in part on the indication.
24. The apparatus of claim 23 , wherein:
the acknowledgement indicates that code blocks within a code block group were successfully decoded; and
the negative-acknowledgement indicates that at least one code block in a code block group was not successfully decoded.
25. The apparatus of claim 23 , further comprising:
means for receiving an indication of a number of code block groups to be formed, wherein code blocks of the plurality of code blocks are grouped based at least in part on the indication of the number of code block groups to be formed.
26. The apparatus of claim 23 , wherein adjacent sets of two or more code blocks of the plurality of code blocks are within a same code block group.
27. A non-transitory computer-readable medium storing code for wireless communication, the code comprising instructions executable by a processor to:
receive a transport block that comprises a plurality of code blocks;
receive an indication to group code blocks of the plurality of code blocks of the transport block for feedback reporting, wherein:
a first set of code blocks of the plurality of code blocks are grouped into one or more code block groups comprising a first quantity of code blocks,
the one or more code block groups of the first quantity of code blocks comprise a first plurality of code block groups of the first quantity of code blocks,
a second set of code blocks of the plurality of code blocks are grouped into one or more code block groups comprising a second quantity of code blocks,
the one or more code block groups of the second quantity of code blocks comprise a second plurality of code block groups of the second quantity of code blocks,
the first quantity of code blocks is different from the second quantity of code blocks, and
each code block group comprises a distinct subset of code blocks of the plurality of code blocks and each code block group of the one or more code block groups comprising the first quantity of code blocks comprises a same number of code blocks; and
transmit an acknowledgement or negative-acknowledgement for each code block group based at least in part on the indication.