Flexible and Simplified Multi-bit Successive-Cancellation List Decoding for Polar Codes

Abstract

Polar codes, as the first channel code that can provably achieve the channel capacity, have received increasing attention these years. However, in practical application, the decoding of polar codes still has many aspects that need improvement. One of the key bottlenecks of polar codes decoding is the high latency of SC (Successive Cancellation) -based decoding algorithms. As one of the solutions to this problem, many SCL (Successive Cancellation List) decoding algorithms with the multi-bit decision are proposed. Despite of the reduction of decoding latency, the complexity spent for computation and sort of path candidates of these algorithms has significantly increased in contrast with the conventional SCL algorithm. In this paper, we propose a novel SCL decoding algorithm with multi-bit decision for polar codes, named as Flexible and Simplified Multi-bit Successive Cancellation List (FSMSCL) decoding. The proposed algorithm further reduces the latency compared to other existing multi-bit decoding algorithms. On the other hand, we provide different path-splitting schemes for different code blocks to control the complexity of computation and sort of path metrics. In the analysis, the experiment results show that the proposed algorithm has similar FER performance compared to the conventional SCL algorithm but its decoding latency outperforms other peer decoding algorithms with multi-bit decision.