Patent ID: 10312948

Abstract:
A hybrid automatic repeat request (HARQ) transmitter in a communications system employing a HARQ process, wherein a primary codeword from an arbitrary forward error correction (FEC) code is sent over a communications channel and negatively acknowledged by a HARQ receiver, includes a polar code retransmission apparatus. A primary codeword buffer stores the primary codeword, and a systematic incremental redundancy (IR) encoder receives a first segment of the primary codeword and encodes the first segment into a first IR codeword. The first segment of the primary codeword excludes at least one symbol of the primary codeword, and the systematic IR encoder comprises a systematic polar encoder. Primary codeword segments, received in response to decoding errors, are encoded into IR codewords, with a kth segment xSof the primary codeword is excluded from retransmission of the kth IR codeword and the IR codewords may be permuted before transmission.