English

Using Intelligent Reflecting Surfaces for Rank Improvement in MIMO Communications

Signal Processing 2020-02-07 v1 Information Theory math.IT

Abstract

An intelligent reflecting surface (IRS), consisting of reconfigurable metamaterials, can be used to partially control the radio environment and thereby bring new features to wireless communications. Previous works on IRS have particularly studied the range extension use case and under what circumstances the new technology can beat relays. In this paper, we study another use case that might have a larger impact on the channel capacity: rank improvement. One of the classical bottlenecks of point-to-point MIMO communications is that the capacity gains provided by spatial multiplexing are only large at high SNR, and high SNR channels are mainly appearing in line-of-sight (LoS) scenarios where the channel matrix has low rank and therefore does not support spatial multiplexing. We demonstrate how an IRS can be used and optimized in such scenarios to increase the rank of the channel matrix, leading to substantial capacity gains.

Keywords

Cite

@article{arxiv.2002.02182,
  title  = {Using Intelligent Reflecting Surfaces for Rank Improvement in MIMO Communications},
  author = {Özgecan Özdogan and Emil Björnson and Erik G. Larsson},
  journal= {arXiv preprint arXiv:2002.02182},
  year   = {2020}
}

Comments

To appear at the 45th International Conference on Acoustics, Speech, and Signal Processing (ICASSP 2020), 5 pages, 5 figures

R2 v1 2026-06-23T13:32:51.493Z