Many-Broadcast Channels: Definition and Capacity in the Degraded Case

Tsung-Yi Chen; Xu Chen; Dongning Guo

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arXiv · 1405.0963

Many-Broadcast Channels: Definition and Capacity in the Degraded Case

Tsung-Yi Chen·Xu Chen·Dongning Guo

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Abstract

Classical multiuser information theory studies the fundamental limits of models with a fixed (often small) number of users as the coding blocklength goes to infinity. Motivated by emerging systems with a massive number of users, this paper studies the new {\em many-user paradigm}, where the number of users is allowed to grow with the blocklength. The focus of this paper is the degraded many-broadcast channel model, whose number of users may grow as fast as linearly with the blocklength. A notion of capacity in terms of message length is defined and an example of Gaussian degraded many-broadcast channel is studied. In addition, a numerical example for the Gaussian degraded many-broadcast channel with fixed transmit power constraint is solved, where every user achieves strictly positive message length asymptotically.

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BibTeX RIS

Tsung-Yi Chen, Xu Chen, Dongning Guo. 2014-05-05. Many-Broadcast Channels: Definition and Capacity in the Degraded Case. https://arxiv.org/abs/1405.0963

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