Decoding Golay Codes and their Related Lattices: A PAC Code Perspective
Yujun Ji, Ling Liu, Shanxiang Lyu, Chao Chen, Tao Dai, Baoming Bai
TL;DR
The paper addresses decoding Golay codes by recasting them through PAC codes, leveraging Forney's cubing construction to build equivalent Golay generators and enabling a parallel list-decoding framework that achieves near-ML performance with small list sizes. It presents three distinct 3×3 kernel-based PAC constructions, each producing a Golay realization without index permutation or puncturing, and combines them into a unified parallel decoding scheme that selects the best result. Beyond Golay codes, the approach extends to multilevel decoding of the Leech lattice’s binary relatives, specifically $\\\\\\\\\\\\\\\\\\\\\\Lambda_{24}$ and $H_{24}$, via a lattice-structured, level-wise decoding pipeline. The results show near-ML performance with modest complexity and demonstrate practical pathways for efficient decoding of related lattice codes with potential applications in higher-dimensional modulation and post-quantum contexts.
Abstract
In this work, we propose a decoding method of Golay codes from the perspective of Polarization Adjusted Convolutional (PAC) codes. By invoking Forney's cubing construction of Golay codes and their generators $G^*(8,7)/(8,4)$, we found different construction methods of Golay codes from PAC codes, which result in an efficient parallel list decoding algorithm with near-maximum likelihood performance. Compared with existing methods, our method can get rid of index permutation and codeword puncturing. Using the new decoding method, some related lattices, such as Leech lattice $Λ_{24}$ and its principal sublattice $H_{24}$, can be also decoded efficiently.
