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arXiv · 1709.02950

Spectral and Energy Efficiency of Cell-Free Massive MIMO Systems with Hardware Impairments

Jiayi Zhang·Yinghua Wei·Emil Björnson·Yu Han·Xu Li
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Abstract

Cell-free massive multiple-input multiple-output (MIMO), with a large number of distributed access points (APs) that jointly serve the user equipments (UEs), is a promising network architecture for future wireless communications. To reduce the cost and power consumption of such systems, it is important to utilize low-quality transceiver hardware at the APs. However, the impact of hardware impairments on cell-free massive MIMO has thus far not been studied. In this paper, we take a first look at this important topic by utilizing well-established models of hardware distortion and deriving new closed-form expressions for the spectral and energy efficiency. These expressions provide important insights into the practical impact of hardware impairments and also how to efficiently deploy cell-free systems. Furthermore, a novel hardware-quality scaling law is presented. It proves that the impact of hardware impairments at the APs vanish as the number of APs grows. Numerical results validate that cell-free massive MIMO systems are inherently resilient to hardware impairments.

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Jiayi Zhang, Yinghua Wei, Emil Björnson, Yu Han, Xu Li. 2017-09-09. Spectral and Energy Efficiency of Cell-Free Massive MIMO Systems with Hardware Impairments. https://arxiv.org/abs/1709.02950

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