Diversity-Multiplexing Tradeoff in Selective-Fading MIMO Channels

Pedro Coronel; Helmut Bölcskei

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arXiv · 0704.3402

Diversity-Multiplexing Tradeoff in Selective-Fading MIMO Channels

Pedro Coronel·Helmut Bölcskei

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Abstract

We establish the optimal diversity-multiplexing (DM) tradeoff of coherent time, frequency and time-frequency selective-fading MIMO channels and provide a code design criterion for DM-tradeoff optimality. Our results are based on the analysis of the "Jensen channel" associated to a given selective-fading MIMO channel. While the original problem seems analytically intractable due to the mutual information being a sum of correlated random variables, the Jensen channel is equivalent to the original channel in the sense of the DM-tradeoff and lends itself nicely to analytical treatment. Finally, as a consequence of our results, we find that the classical rank criterion for space-time code design (in selective-fading MIMO channels) ensures optimality in the sense of the DM-tradeoff.

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Pedro Coronel, Helmut Bölcskei. 2007-04-25. Diversity-Multiplexing Tradeoff in Selective-Fading MIMO Channels. https://arxiv.org/abs/0704.3402

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