An efficient length- and rate-preserving concatenation of polar and repetition codes

TL;DR

This paper presents an improved method for enhancing polar codes' finite-length performance by concatenating them with repetition codes, maintaining rate and length while only modestly increasing decoding complexity.

Contribution

It introduces a rate- and length-preserving concatenation scheme that integrates seamlessly with existing polar decoding algorithms, offering performance gains with minimal complexity increase.

Findings

Decoding complexity at most doubles.

Performance improvement over previous methods.

Compatible with existing polar decoding algorithms.

Abstract

We improve the method in \cite{Seidl:10} for increasing the finite-lengh performance of polar codes by protecting specific, less reliable symbols with simple outer repetition codes. Decoding of the scheme integrates easily in the known successive decoding algorithms for polar codes. Overall rate and block length remain unchanged, the decoding complexity is at most doubled. A comparison to related methods for performance improvement of polar codes is drawn.