A novel puncturing pattern selection with feedback values for polar code

Abstract

Polar codes are proven as the first codes to achieve the limit of channel capacity and have been adopted in 5G. Due to their construction characteristics and performance, they are expected to be utilized for flexible scenarios in 6G. For a given length of information, various code rates can be achieved by changing the number of frozen bits and by puncturing techniques. However, the arbitrary code rate is limited due to the core matrix, and the decoding performance is degraded resulting from the puncturing techniques. In order to improve the performance, this paper proposes a novel puncturing pattern selection scheme using an additional encoding process based on feedback values at the transmitter. The proposed scheme guarantees the punctured codeword bits to be definitely known by the receiver. As a consequence, the log-likelihood ratio (LLR) of the punctured codeword bits can be accordingly set to infinity at the decoder, resulting in the performance improvement. Simulation results demonstrate that the proposed puncturing scheme outperforms the existing schemes with a slightly increased complexity.