Diversity-Multiplexing Tradeoff in the Low-SNR Regime

Sergey Loyka; Georgy Levin

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arXiv · 1102.5365

Diversity-Multiplexing Tradeoff in the Low-SNR Regime

Sergey Loyka·Georgy Levin

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Abstract

An extension of the popular diversity-multiplexing tradeoff framework to the low-SNR (or wideband) regime is proposed. The concept of diversity gain is shown to be redundant in this regime since the outage probability is SNR-independent and depends on the multiplexing gain and the channel power gain statistics only. The outage probability under the DMT framework is obtained in an explicit, closed form for a broad class of channels. The low and high-SNR regime boundaries are explicitly determined for the scalar Rayleigh-fading channel, indicating a significant limitation of the SNR-asymptotic DMT when the multiplexing gain is small.

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Sergey Loyka, Georgy Levin. 2011-02-25. Diversity-Multiplexing Tradeoff in the Low-SNR Regime. https://arxiv.org/abs/1102.5365

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