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arXiv · 2410.17872

A Method to Reduce the Complexity of Computing the Complete Weight Distribution of Polar Codes

Zhichao Liu·Zhiming Ma·Guiying Yan
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Abstract

The code spectrum of polar codes is crucial to the performance of polar codes. Based on the lower-triangular affine group (LTA) of decreasing monomial codes and the one-variable descendance (ovd) relation, we define a new subgroup of LTA which can find more cosets with the same weight distribution. Using this algebraic structure, we further reduce the complexity by proofing the group action on a coset set is transitive. Our method is an enhanced version of previous research, and the complexity of most cases can be reduced exceeding several times.

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Zhichao Liu, Zhiming Ma, Guiying Yan. 2024-10-23. A Method to Reduce the Complexity of Computing the Complete Weight Distribution of Polar Codes. https://arxiv.org/abs/2410.17872

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