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arXiv · 2103.00971

Low-Complexity Zero-Forcing Precoding for XL-MIMO Transmissions

Lucas N. Ribeiro·Stefan Schwarz·Martin Haardt
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Abstract

Deploying antenna arrays with an asymptotically large aperture will be central to achieving the theoretical gains of massive MIMO in beyond-5G systems. Such extra-large MIMO (XL-MIMO) systems experience propagation conditions which are not typically observed in conventional massive MIMO systems, such as spatial non-stationarities and near-field propagation. Moreover, standard precoding schemes, such as zero-forcing (ZF), may not apply to XL-MIMO transmissions due to the prohibitive complexity associated with such a large-scale scenario. We propose two novel precoding schemes that aim at reducing the complexity without losing much performance. The proposed schemes leverage a plane-wave approximation and user grouping to obtain a low-complexity approximation of the ZF precoder. Our simulation results show that the proposed schemes offer a possibility for a performance and complexity trade-off compared to the benchmark schemes.

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Lucas N. Ribeiro, Stefan Schwarz, Martin Haardt. 2021-03-01. Low-Complexity Zero-Forcing Precoding for XL-MIMO Transmissions. https://arxiv.org/abs/2103.00971

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