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arXiv · 2205.15642

How Should IRSs Scale to Harden Multi-Antenna Channels?

Ali Bereyhi·Saba Asaad·Chongjun Ouyang·Ralf R. Müller·Rafael F. Schaefer·H. Vincent Poor
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Abstract

This work extends the concept of channel hardening to multi-antenna systems that are aided by intelligent reflecting surfaces (IRSs). For fading links between a multi-antenna transmitter and a single-antenna receiver, we derive an accurate approximation for the distribution of the input-output mutual information when the number of reflecting elements grows large. The asymptotic results demonstrate that by increasing the number of elements on the IRS, the end-to-end channel hardens as long as the physical dimensions of the IRS grow as well. The growth rate however need not to be of a specific order and can be significantly sub-linear. The validity of the analytical result is confirmed by numerical experiments.

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Ali Bereyhi, Saba Asaad, Chongjun Ouyang, Ralf R. Müller, Rafael F. Schaefer, H. Vincent Poor. 2022-05-31. How Should IRSs Scale to Harden Multi-Antenna Channels?. https://arxiv.org/abs/2205.15642

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