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arXiv · 1903.03085

Non-Stationarities in Extra-Large Scale Massive MIMO

Elisabeth De Carvalho·Anum Ali·Abolfazl Amiri·Marko Angjelichinoski·Robert W. Heath Jr
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Abstract

Massive MIMO, a key technology for increasing area spectral efficiency in cellular systems, was developed assuming moderately sized apertures. In this paper, we argue that massive MIMO systems behave differently in large-scale regimes due to spatial non-stationarity. In the large-scale regime, with arrays of around fifty wavelengths, the terminals see the whole array but non-stationarities occur because different regions of the array see different propagation paths. At even larger dimensions, which we call the extra-large scale regime, terminals see a portion of the array and inside the first type of non-stationarities might occur. We show that the non-stationarity properties of the massive MIMO channel changes several important MIMO design aspects. In simulations, we demonstrate how non-stationarity is a curse when neglected but a blessing when embraced in terms of computational load and multi-user transceiver design.

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Elisabeth De Carvalho, Anum Ali, Abolfazl Amiri, Marko Angjelichinoski, Robert W. Heath Jr. 2019-03-07. Non-Stationarities in Extra-Large Scale Massive MIMO. https://arxiv.org/abs/1903.03085

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