METHODS, APPARATUS, SYSTEMS AND PROCEDURES FOR HYBRID AUTOMATIC REPEAT REQUESTS (HARQs) USING POLAR CODES

A method implemented by a wireless transmit/receive unit (WTRU) or a network entity, as a transmitting node (TN), using a set of input bits, the method comprising:

• determining a shortening number (SN) associated with a shortening operation for generation of a first transmission;
• generating, by the TN from the set of input bits, a first set of polar coded bits (PCBs), the first set of PCBs to provide data or control information;
• sending, by the TN to a receiving node (RN) in the first transmission, the first set of PCBs shortened in accordance with the SN;
• on condition that the SN exceeds a threshold, generating, by the TN from a MCB associated with the set of input bits, a second set of PCBs;
• on condition that the SN does not exceed the threshold, generating, by the TN from a shortened polar code block associated with the set of input bits, the second set of PCBs;
• and
• sending, by the TN to the RN, the generated second set of PCBs in a second transmission.

A Transmitting Node (TN), comprising:

• a processor configured to:
• apply a shortening operation to generate a first set of polar coded bits (PCBs), and
• select one code generating operation of a plurality of code generating operations based on at least a number of shortened bits associated with the shortened polar code block after the shortening operation;
• a circular buffer configured to store a second set of PCBs based on the first set of PCBs or based on the MCB in accordance with the selected code generating operation;
• a wireless transmitter/receiver configured to send the first set of PCBs or an interleaved copy of the first set of PCBs in a first transmission;
• wherein:
• the TN is configured to, on condition that the first transmission was not successful, output from the circular buffer, a copy of a part of the second set of PCBs for transmission;
• and
• the wireless transmitter/receiver is configured to send the copy of the part of the second set of PCBs in a second transmission.