Diversity versus Channel Knowledge at Finite Block-Length

Wei Yang; Giuseppe Durisi; Tobias Koch; Yury Polyanskiy

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arXiv · 1204.2927

Diversity versus Channel Knowledge at Finite Block-Length

Wei Yang·Giuseppe Durisi·Tobias Koch·Yury Polyanskiy

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Abstract

We study the maximal achievable rate R*(n, \epsilon) for a given block-length n and block error probability \epsilon over Rayleigh block-fading channels in the noncoherent setting and in the finite block-length regime. Our results show that for a given block-length and error probability, R*(n, \epsilon) is not monotonic in the channel's coherence time, but there exists a rate maximizing coherence time that optimally trades between diversity and cost of estimating the channel.

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Wei Yang, Giuseppe Durisi, Tobias Koch, Yury Polyanskiy. 2012-04-13. Diversity versus Channel Knowledge at Finite Block-Length. https://arxiv.org/abs/1204.2927

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