Polar coding systems, procedures, and signaling
Systems, methods, and instrumentalities are disclosed for interleaving coded bits. A wireless transmit/receive unit (WTRU) may generate a plurality of polar encoded bits using polar encoding. The WTRU may divide the plurality of polar encoded bits into sub-blocks of equal size in a sequential manner. The WTRU may apply sub-block wise interleaving to the sub-blocks using an interleaver pattern. The sub-blocks associated with a subset of the sub-blocks may be interleaved, and sub-blocks associated with another subset of the sub-blocks may not be interleaved. The sub-block wise interleaving may include applying interleaving across the sub-blocks without interleaving bits associated with each of the sub-blocks. The WTRU may concatenate bits from each of the interleaved sub-blocks to generate interleaved bits, and store the interleaved bits associated with the interleaved sub-blocks in a circular buffer. The WTRU may select a plurality of bits for transmission from the interleaved bits.
1. A method implemented by a wireless transmit/receive unit (WTRU), the method comprising:
generating a plurality of uplink control information (UCI) bits to be transmitted in a codeword;
applying a polar code to the UCI bits, wherein a mother code length associated with the polar code is determined based on a codeword length for transmission of the UCI;
performing rate matching on the polar coded UCI bits, wherein performing the rate matching comprises performing one of:
a repetition scheme if the mother code length is less than the codeword length,
a puncturing scheme if a code rate for the codeword is less than a threshold, or
a shortening scheme if the code rate for the codeword is greater than the threshold; and
transmitting the rate matched, polar coded UCI bits.
2. The method of claim 1 , wherein the mother code length is determined based on the code rate.
3. The method of claim 1 , wherein the codeword further includes a plurality of cyclic redundancy check (CRC) bits.
4. The method of claim 1 , wherein the code rate corresponds to a number of UCI bits and cyclic redundancy check (CRC) bits in the codeword divided by a number of coded bits in the codeword.
5. The method of claim 1 , wherein the puncturing scheme or the shortening scheme is performed if the mother code length is greater than the codeword length.
6. The method of claim 1 , wherein performing the rate matching further comprises:
selecting the repetition scheme if the mother code length is less than the codeword length, or
if the repetition scheme is not selected, selecting one of the puncturing scheme or the shortening scheme.
7. The method of claim 1 , wherein the polar code comprises a concatenated polar code.
8. The method of claim 7 , further comprising performing one of the repetition scheme, the puncturing scheme, or the shortening scheme to the concatenated polar code.
9. A wireless transmit/receive unit (WTRU) comprising:
a transceiver; and
a processor configured to:
generate a plurality of uplink control information (UCI) bits to be transmitted in a codeword;
apply a polar code to the UCI bits, wherein a mother code length associated with the polar code is determined based on a codeword length for transmission of the UCI;
perform rate matching on the polar coded UCI bits, wherein the rate matching is performed using one of:
a repetition scheme if the mother code length is less than the codeword length,
a puncturing scheme if a code rate for the codeword is less than a threshold, or
a shortening scheme if the code rate for the codeword is greater than the threshold; and
transmit the rate matched, polar coded UCI bits.
10. The WTRU of claim 9 , wherein the mother code length is determined based on the code rate.
11. The WTRU of claim 9 , wherein the codeword further includes a plurality of cyclic redundancy check (CRC) bits.
12. The WTRU of claim 9 , wherein the code rate corresponds to a number of UCI bits and cyclic redundancy check (CRC) bits in the codewords divided by a number of coded bits in the codeword.
13. The WTRU of claim 9 , wherein the puncturing scheme or the shortening scheme is performed if the mother code length is greater than the codeword length.
14. The WTRU of claim 9 , wherein the processor is further configured to perform rate matching by:
selecting the repetition scheme if the mother code length is less than the codeword length, or
if the repetition scheme is not selected, selecting one of the puncturing scheme or the shortening scheme.
15. The WTRU of claim 9 , wherein the polar code comprises a concatenated polar code.
16. The WTRU of claim 15 , wherein the processor is further configured to perform one of the repetition scheme, the puncturing scheme, or the shortening scheme to the concatenated polar code.