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arXiv · 2608.19869

Sub-optimality of Marton's Inner Bound for the Two-Receiver Broadcast Channel

Mian Huang·Yanxiao Liu·Yi Liu
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Abstract

Marton's inner bound, the best-known achievable region for a general discrete memoryless broadcast channel, was proposed by Katalin Marton in 1979, and whether it always achieves the capacity region has remained open since then. In this paper, we establish its strict sub-optimality: we show that the capacity region of some discrete memoryless broadcast channels can be strictly larger than Marton's inner bound.

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Mian Huang, Yanxiao Liu, Yi Liu. 2026-08-20. Sub-optimality of Marton's Inner Bound for the Two-Receiver Broadcast Channel. https://arxiv.org/abs/2608.19869

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