On Decoding First- and Second-Order BiD Codes

Devansh Jain; Lakshmi Prasad Natarajan

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arXiv · 2601.09390

On Decoding First- and Second-Order BiD Codes

Devansh Jain·Lakshmi Prasad Natarajan

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Abstract

BiD codes, which are a new family of algebraic codes of length $3^m$, achieve the erasure channel capacity under bit-MAP decoding and offer asymptotically larger minimum distance than Reed-Muller (RM) codes. In this paper we propose fast maximum-likelihood (ML) and max-log-MAP decoders for first-order BiD codes. For second-order codes, we identify their minimum-weight parity checks and ascertain a code property known as 'projection' in the RM coding literature. We use these results to design a belief propagation decoder that performs within 1 dB of ML decoder for block lengths 81 and 243.

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Devansh Jain, Lakshmi Prasad Natarajan. 2026-01-14. On Decoding First- and Second-Order BiD Codes. https://arxiv.org/abs/2601.09390

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