Methods and apparatus for determining transport block size in wireless communication
Apparatuses and methods are disclosed for determining a transport block size (TBS) as a function of various parameters without cyclic dependencies between the parameters and TBS. The disclosed function can determine a TBS in a single pass, and the determined TBS allows the use of code blocks with equal code block size (CBS) in a transport block segmentation process. The determined TBS can provide byte-aligned code block lengths and require no padding bits in a transport block.
1. A method of transmitting data in a transport block (TB) in wireless communication, comprising:
determining an intermediate value based on a number of resource elements, a modulation order, a code rate, and a number of MIMO layers for transmitting the TB;
selecting a maximum code block size from a plurality of maximum code block sizes;
determining a number of code blocks associated with the TB based on the intermediate value and the selected maximum code block size;
determining a code block size based on the number of code blocks;
determining a transport block size (TBS) for the TB as a function of the code block size, the number of code blocks, and a rate back-off factor; and
transmitting the TB using the determined TBS,
wherein the rate back-off factor has a value dependent at least on Qm, R, and v, where Qm is a modulation order, R is a code rate, and v is a number of multiple-input multiple-output MIMO layers.
2. The method of claim 1 , wherein the determining the code block size comprises determining a code block (CB) level cyclic redundancy check (CRC) size by selecting the CB level CRC size from a plurality of predetermined CRC sizes based on the intermediate value.
3. The method of claim 2 , wherein the determining the code block size further comprises determining a byte-aligned code block size.
4. The method of claim 1 , wherein the determining the TBS further comprises determining a TB level cyclic redundancy check (CRC) size by selecting the TB level CRC size from a plurality of predetermined CRC sizes based on the intermediate value.
5. The method of claim 1 , wherein the determining the TBS further comprises determining the TBS without cyclic dependencies between the TBS, a selected base graph, and the code block size.
6. The method of claim 5 , further comprising:
selecting the base graph based on at least one of the code rate or the intermediate value; and
determining the maximum code block size based on the selected base graph.
7. The method of claim 1 , wherein the transmitting the TB comprises transmitting the TB with no padding bits.
8. The method of claim 1 , wherein the determining the TBS comprises:
determining the TBS using a non-recursive function of the code block size and the number of code blocks.
9. An apparatus of wireless communication, comprising:
a communication interface configured to transmit data in a transport block (TB);
a memory; and
a processor coupled with the communication interface and the memory,
wherein the processor and the memory are configured to:
determine an intermediate value based on a number of resource elements, a modulation order, a code rate, and a number of MIMO layers for transmitting the TB;
select a maximum code block size from a plurality of maximum code block sizes;
determine a number of code blocks associated with the TB based on the intermediate value;
determine a code block size based on the number of code blocks;
determine a transport block size (TBS) for the TB as a function of the code block size, the number of code blocks, and a rate back-off factor; and
transmit the TB using the determined TBS,
wherein the rate back-off factor has a value dependent at least on Qm, R, and v, where Qm is a modulation order, R is a code rate, and v is a number of multiple-input multiple-output MIMO lavers.
10. The apparatus of claim 9 , wherein, to determine the code block size, the processor and the memory are further configured to:
determine a code block (CB) level cyclic redundancy check (CRC) size by selecting the CB level CRC size from a plurality of predetermined CRC sizes based on the intermediate value.
11. The apparatus of claim 10 , wherein, to determine the code block size, the processor and the memory are further configured to:
determine a byte-aligned code block size.
12. The apparatus of claim 9 , wherein, to determine the TBS, the processor and the memory are further configured to:
determine a TB level cyclic redundancy check (CRC) size by selecting the TB level CRC size from a plurality of predetermined CRC sizes based on the intermediate value.
13. The apparatus of claim 9 , wherein, to determine the TBS, the processor and the memory are further configured to:
determine the TBS without cyclic dependencies between the TBS, a selected base graph, and the code block size.
14. The apparatus of claim 13 , wherein the processor and the memory are further configured to:
select the base graph based on at least one of the code rate or the intermediate value; and
determine the maximum code block size based on the selected base graph.
15. The apparatus of claim 9 , wherein, to transmit the TB, the processor and the memory are further configured to:
transmit the TB with no padding bits.
16. The apparatus of claim 9 , wherein, to determine the TBS, the processor and the memory are further configured to:
determine the TBS as a non-recursive function of the code block size and the number of code blocks.
17. An apparatus of wireless communication, comprising:
means for determining an intermediate value based on a number of resource elements, a modulation order, a code rate, and a number of MIMO layers for transmitting a transport block (TB);
means for selecting a maximum code block size from a plurality of maximum code block sizes;
means for determining a number of code blocks associated with the TB based on the intermediate value and the selected maximum code block size;
means for determining a code block size based on the number of code blocks;
means for determining a transport block size (TBS) for the TB as a function of the code block size, the number of code blocks, and a rate back-off factor; and
means for transmitting the TB using the determined TBS,
wherein the rate back-off factor has a value dependent at least on Qm, R, and v, where Qm is a modulation order, R is a code rate, and v is a number of multiple-input multiple-output MIMO layers.
18. A non-transitory computer-readable medium comprising executable code stored thereon which, when executed by a processor, causes an apparatus for wireless communication to:
determine an intermediate value based on a number of resource elements, a modulation order, a code rate, and a number of MIMO layers for transmitting a transport block (TB);
selecting a maximum code block size from a plurality of maximum code block sizes;
determine a number of code blocks associated with the TB based on the intermediate value and the selected maximum code block size;
determine a code block size based on the number of code blocks;
determine a transport block size (TBS) for the TB as a function of the code block size, the number of code blocks, and a rate back-off factor; and
transmit the TB using the determined TBS,
wherein the rate back-off factor has a value dependent at least on Qm, R, and v, where Qm is a modulation order, R is a code rate, and v is a number of multiple-input multiple-output MIMO lavers.