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arXiv · 1811.09525

Sum-Rate Capacity for Symmetric Gaussian Multiple Access Channels with Feedback

Erixhen Sula·Michael Gastpar·Gerhard Kramer
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Abstract

The feedback sum-rate capacity is established for the symmetric $J$-user Gaussian multiple-access channel (GMAC). The main contribution is a converse bound that combines the dependence-balance argument of Hekstra and Willems (1989) with a variant of the factorization of a convex envelope of Geng and Nair (2014). The converse bound matches the achievable sum-rate of the Fourier-Modulated Estimate Correction strategy of Kramer (2002).

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Erixhen Sula, Michael Gastpar, Gerhard Kramer. 2018-11-23. Sum-Rate Capacity for Symmetric Gaussian Multiple Access Channels with Feedback. https://arxiv.org/abs/1811.09525

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