An Analysis of RPA Decoding of Reed-Muller Codes Over the BSC

V. Arvind Rameshwar; V. Lalitha

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arXiv · 2412.08129

An Analysis of RPA Decoding of Reed-Muller Codes Over the BSC

V. Arvind Rameshwar·V. Lalitha

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Abstract

In this paper, we revisit the Recursive Projection-Aggregation (RPA) decoder, of Ye and Abbe (2020), for Reed-Muller (RM) codes. Our main contribution is an explicit upper bound on the probability of incorrect decoding, using the RPA decoder, over a binary symmetric channel (BSC). Importantly, we focus on the events where a \emph{single} iteration of the RPA decoder, in each recursive call, is sufficient for convergence. Key components of our analysis are explicit estimates of the probability of incorrect decoding of first-order RM codes using a maximum likelihood (ML) decoder, and estimates of the error probabilities during the aggregation phase of the RPA decoder. Our results allow us to show that for RM codes with blocklength $N = 2^m$, the RPA decoder can achieve vanishing error probabilities, in the large blocklength limit, for RM orders that grow roughly logarithmically in $m$.

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V. Arvind Rameshwar, V. Lalitha. 2024-12-11. An Analysis of RPA Decoding of Reed-Muller Codes Over the BSC. https://arxiv.org/abs/2412.08129

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