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arXiv · 2302.10587

LSFD for Rician-Faded Cell-Free mMIMO Systems With Channel Aging and Hardware Impairments

Anish Chattopadhyay·Venkatesh Tentu·Dheeraj Naidu Amudala·Rohit Budhiraja
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Abstract

We study the impact of channel aging on the uplink of a cell-free massive multiple-input multiple-output system with hardware impairments. We consider a dynamic analog-to-digital converter architecture at the access points (APs), and low-resolution digital-to-analog converters at the user equipments (UEs). We derive a closed-form spectral efficiency expression by considering i) practical spatially-correlated Rician channels; ii) hardware impairments at the APs and the UEs; iii) channel aging; and iv) large-scale fading decoding (LSFD). We show that LSFD can effectively mitigate the detrimental effects of i) channel aging for both low and high UE velocities; and ii) inter-user interference for low-velocity UEs but not for high-velocity UEs.

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Anish Chattopadhyay, Venkatesh Tentu, Dheeraj Naidu Amudala, Rohit Budhiraja. 2023-02-21. LSFD for Rician-Faded Cell-Free mMIMO Systems With Channel Aging and Hardware Impairments. https://doi.org/10.1109/icc45041.2023.10278616

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