On the Capacity of Fading MIMO Broadcast Channels with Imperfect Transmitter Side-Information

Amos Lapidoth; Shlomo Shamai; Michele Wigger

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On the Capacity of Fading MIMO Broadcast Channels with Imperfect Transmitter Side-Information

Amos Lapidoth·Shlomo Shamai·Michele Wigger

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Abstract

A fading broadcast channel is considered where the transmitter employs two antennas and each of the two receivers employs a single receive antenna. It is demonstrated that even if the realization of the fading is precisely known to the receivers, the high signal-to-noise (SNR) throughput is greatly reduced if, rather than knowing the fading realization \emph{precisely}, the trasmitter only knows the fading realization \emph{approximately}. The results are general and are not limited to memoryless Gaussian fading.

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Amos Lapidoth, Shlomo Shamai, Michele Wigger. 2006-05-17. On the Capacity of Fading MIMO Broadcast Channels with Imperfect Transmitter Side-Information. https://arxiv.org/abs/cs/0605079

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