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arXiv · 2106.04280

Optimizing a Binary Intelligent Reflecting Surface for OFDM Communications under Mutual Coupling

Abstract

An intelligent reflecting surface (IRS) can greatly improve the channel quality over a frequency-flat channel, if it is configured to reflect the incident signal as a beam towards the receiver. However, the fundamental limitations of the IRS technology become apparent over practical frequency-selective channels, where the same configuration must be used over the entire bandwidth. In this paper, we consider a wideband orthogonal frequency-division multiplexing (OFDM) system that is supported by a fairly realistic IRS setup with two unbalanced states per element and also mutual coupling. We describe the simulation setup considered in the IEEE Signal Processing Cup 2021, propose a low-complexity solution for channel estimation and IRS configuration, and evaluate it on that setup.

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Emil Björnson. 2021-09-14. Optimizing a Binary Intelligent Reflecting Surface for OFDM Communications under Mutual Coupling. https://arxiv.org/abs/2106.04280

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