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arXiv · 2606.12839

The Capacity Region for Classes of Sum-Broadcast Channels

Amin Gohari·Yi Liu·Chandra Nair
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Abstract

We compute the capacity region of a sum of broadcast channels whose components are degraded, less-noisy, more-capable, deterministic, or semi-deterministic. We achieve this by showing that an auxiliary-receiver outer bound, previously introduced by some of the authors, matches Marton's inner bound. This result generalizes a previously known result for the sum of two reversely degraded broadcast channels due to El Gamal (1980). Moreover, we define a class of primary broadcast channels and show an analogous result for the sum of primary broadcast channels.

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Amin Gohari, Yi Liu, Chandra Nair. 2026-06-11. The Capacity Region for Classes of Sum-Broadcast Channels. https://arxiv.org/abs/2606.12839

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