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arXiv · 1510.06827

Sum-Rate and Power Scaling of Massive MIMO Systems with Channel Aging

Chuili Kong·Caijun Zhong·Anastasios K. Papazafeiropoulos·Michail Matthaiou·Zhaoyang Zhang
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Abstract

This paper investigates the achievable sum-rate of massive multiple-input multiple-output (MIMO) systems in the presence of channel aging. For the uplink, by assuming that the base station (BS) deploys maximum ratio combining (MRC) or zero-forcing (ZF) receivers, we present tight closed-form lower bounds on the achievable sum-rate for both receivers with aged channel state information (CSI). In addition, the benefit of implementing channel prediction methods on the sum-rate is examined, and closed-form sum rate lower bounds are derived. Moreover, the impact of channel aging and channel prediction on the power scaling law is characterized. Extension to the downlink scenario and multi-cell scenario are also considered. It is found that, for a system with/without channel prediction, the transmit power of each user can be scaled down at most by $1/\sqrt{M}$ (where $M$ is the number of BS antennas), which indicates that aged CSI does not degrade the power scaling law, and channel prediction does not enhance the power scaling law; instead, these phenomena affect the achievable sum-rate by degrading or enhancing the effective signal to interference and noise ratio, respectively.

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Chuili Kong, Caijun Zhong, Anastasios K. Papazafeiropoulos, Michail Matthaiou, Zhaoyang Zhang. 2015-10-23. Sum-Rate and Power Scaling of Massive MIMO Systems with Channel Aging. https://doi.org/10.1109/tcomm.2015.2493998

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