The Capacity Region of the Broadcast Channel with Non-Signaling Assistance

Yuhang Yao; Syed A. Jafar

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arXiv · 2607.27434

The Capacity Region of the Broadcast Channel with Non-Signaling Assistance

Yuhang Yao·Syed A. Jafar

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Abstract

The capacity region of the $K$-user discrete memoryless broadcast channel is fully characterized when non-signaling (NS) assistance is available to the transmitter and all $K$ receivers. The NS-assisted capacity region is shown to coincide with Sato's region, i.e., the region defined by sum-rate bounds over all subsets of messages, where each bound corresponds to full cooperation among that subset of receivers under a worst-case joint channel law consistent with the marginal channels.

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Yuhang Yao, Syed A. Jafar. 2026-07-29. The Capacity Region of the Broadcast Channel with Non-Signaling Assistance. https://arxiv.org/abs/2607.27434

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