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arXiv · 1705.06804

Antenna Arrays for Line-of-Sight Massive MIMO: Half Wavelength is not Enough

Daniele Pinchera·Marco Donald Migliore·Fulvio Schettino·Gaetano Panariello
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Abstract

The aim of this paper is to analyze the array synthesis for 5 G massive MIMO systems in the line-of-sight working condition. The main result of the numerical investigation performed is that non-uniform arrays are the natural choice in this kind of application. In particular, by using non-equispaced arrays, we show that it is possible to achieve a better average condition number of the channel matrix and a significantly higher spectral efficiency. Furthermore, we verify that increasing the array size is beneficial also for circular arrays, and we provide some useful rules-of-thumb for antenna array design for massive MIMO applications. These results are in contrast to the widely-accepted idea in the 5 G massive MIMO literature, in which the half-wavelength linear uniform array is universally adopted.

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Daniele Pinchera, Marco Donald Migliore, Fulvio Schettino, Gaetano Panariello. 2017-09-01. Antenna Arrays for Line-of-Sight Massive MIMO: Half Wavelength is not Enough. https://doi.org/10.3390/electronics6030057

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