Fast-SSC-Flip Decoding of Polar Codes

TL;DR

This paper introduces a modified fast-SSC-flip decoding algorithm for polar codes that significantly improves decoding speed while maintaining comparable error-correction performance, making it suitable for high-speed hardware applications.

Contribution

It presents a novel modification of the fast-SSC decoding algorithm to incorporate SC-flip ideas, achieving faster decoding with similar error correction.

Findings

Decoding speed improved by nearly an order of magnitude.

Error-correction performance remains comparable to existing methods.

Algorithm is tailored for efficient hardware implementation.

Abstract

Polar codes are widely considered as one of the most exciting recent discoveries in channel coding. For short to moderate block lengths, their error-correction performance under list decoding can outperform that of other modern error-correcting codes. However, high-speed list-based decoders with moderate complexity are challenging to implement. Successive-cancellation (SC)-flip decoding was shown to be capable of a competitive error-correction performance compared to that of list decoding with a small list size, at a fraction of the complexity, but suffers from a variable execution time and a higher worst-case latency. In this work, we show how to modify the state-of-the-art high-speed SC decoding algorithm to incorporate the SC-flip ideas. The algorithmic improvements are presented as well as average execution-time results tailored to a hardware implementation. The results show that the proposed fast-SSC-flip algorithm has a decoding speed close to an order of magnitude better than the previous works while retaining a comparable error-correction performance.