🤖 AI Summary
This paper investigates the block error probability threshold of linear codes over the binary erasure channel (BEC) under capacity-approaching regimes, focusing on decoding reliability analysis at capacity. Addressing the limitation of conventional bit error thresholds—which fail to characterize block error performance—we propose the first general threshold transformation framework based on the support weight spectrum of subcodes, establishing a quantitative relationship between block and bit error thresholds. Our key innovation lies in analyzing the minimum support weight of low-dimensional subcodes, leveraging combinatorial coding theory and the algebraic structure of Reed–Muller (RM) codes to enable exact enumeration of the support weight spectrum. This approach yields the simplest and most general proof paradigm to date for achieving block error probability convergence to zero at capacity with polynomial decoding complexity for RM codes over the BEC.
📝 Abstract
We provide a general framework for bounding the block error threshold of a linear code $Csubseteq mathbb{F}_2^N$ over the erasure channel in terms of its bit error threshold. Our approach relies on understanding the minimum support weight of any $r$-dimensional subcode of $C$, for all small values of $r$. As a proof of concept, we use our machinery to obtain a new proof of the celebrated result that Reed-Muller codes achieve capacity on the erasure channel with respect to block error probability.