Optimal 1-bit Error Exponent for 2-hop Relaying with Binary-Input Channels

Yan Hao Ling; Jonathan Scarlett

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arXiv · 2311.14251

Optimal 1-bit Error Exponent for 2-hop Relaying with Binary-Input Channels

Yan Hao Ling·Jonathan Scarlett

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Abstract

In this paper, we study the problem of relaying a single bit over a tandem of binary-input channels, with the goal of attaining the highest possible error exponent in the exponentially decaying error probability. Our previous work gave an exact characterization of the best possible error exponent in various special cases, including when the two channels are identical, but the general case was left as an open problem. We resolve this open problem by deriving a new converse bound that matches our existing achievability bound.

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Yan Hao Ling, Jonathan Scarlett. 2023-11-24. Optimal 1-bit Error Exponent for 2-hop Relaying with Binary-Input Channels. https://arxiv.org/abs/2311.14251

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