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arXiv · 1703.07191

Optimal DoF region of the K-User MISO BC with Partial CSIT

Enrico Piovano·Bruno Clerckx
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Abstract

We consider the $K$-User Multiple-Input-Single-Output (MISO) Broadcast Channel (BC) where the transmitter, equipped with $M$ antennas, serves $K$ users, with $K \leq M$. The transmitter has access to a partial channel state information of the users. This is modelled by letting the variance of the Channel State Information at the Transmitter (CSIT) error of user $i$ scale as $O(P^{-\alpha_i}$) for the Signal-to-Noise Ratio (SNR) $P$ and some constant $\alpha_i \geq 0$. In this work we derive the optimal Degrees-of-Freedom (DoF) region in such setting and we show that Rate-Splitting (RS) is the key scheme to achieve such a region.

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Enrico Piovano, Bruno Clerckx. 2017-03-21. Optimal DoF region of the K-User MISO BC with Partial CSIT. https://arxiv.org/abs/1703.07191

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