Retransmission of physical uplink control channel (PUCCH) for ultra reliable low latency communications (URLLC)

A method for wireless communication by a Base Station (BS), comprising:

• receiving a transmission of at least one code block of a control channel, the at least one code block including Channel State Information (CSI), wherein:
• bit indices of the at least one code block are assigned to bit channels in a particular order of reliabilities of the bit channels, and
• the at least one code block, including the CSI, is polar encoded based on the bit indices assigned in the particular order of reliabilities of the bit channels;
• receiving a retransmission of at least a portion of the at least one code block including the CSI, wherein:
• bit indices of the portion of the at least one code block, including the CSI, are assigned to the bit channels in a reverse order of reliabilities of the bit channels as compared to the particular order of reliabilities of the bit channels, and
• the portion of the at least one code block, including the CSI, is polar encoded based on the bit indices assigned in the reverse order of reliabilities of the bit channels;
• and
• decoding the at least one code block based on the transmission and the retransmission.

An apparatus for wireless communication by a User Equipment (UE), comprising:

• means for assigning bit indices of at least one code block of a control channel to bit channels in a particular order of reliabilities of the bit channels, the at least one code block including Channel State Information (CSI);
• means for polar encoding the at least one code block, including the CSI, based on the bit indices assigned in the particular order of reliabilities of the bit channels;
• means for transmitting the polar encoded at least one code block, including the CSI;
• means for detecting a trigger;
• means for assigning, in response to the trigger, the bit indices of at least a portion of the at least one code block, including the CSI, to the bit channels in a reverse order of reliabilities of the bit channels as compared to the particular order of reliabilities of the bit channels;
• means for polar encoding the portion of the at least one code block, including the CSI, based on the bit indices assigned in the reverse order of reliabilities of the bit channels;
• and
• means for retransmitting the polar encoded portion of the at least one code block, including the CSI.

An apparatus for wireless communication by a Base Station (BS), comprising:

• means for receiving a transmission of at least one code block of a control channel, the at least one code block including Channel State Information (CSI), wherein:
• bit indices of the at least one code block are assigned to bit channels in a particular order of reliabilities of the bit channels, and
• the at least one code block, including the CSI, is polar encoded based on the bit indices assigned in the particular order of reliabilities of the bit channels;
• means for receiving a retransmission of at least a portion of the at least one code block including the CSI, wherein:
• bit indices of the portion of the at least one code block, including the CSI, are assigned to the bit channels in a reverse order of reliabilities of the bit channels as compared to the particular order of reliabilities of the bit channels, and
• the portion of the at least one code block, including the CSI, is polar encoded based on the bit indices assigned in the reverse order of reliabilities of the bit channels;
• and
• means for decoding the at least one code block based on the transmission and the retransmission.