Reconfigurable Intelligent Surface: MIMO or radiating sheet?

@article{Droulias2022ReconfigurableIS,
  title={Reconfigurable Intelligent Surface: MIMO or radiating sheet?},
  author={Sotiris Droulias and Angeliki Alexiou},
  journal={ArXiv},
  year={2022},
  volume={abs/2205.08819}
}
A Reconfigurable Intelligent Surface (RIS) redirects and possibly modifies the properties of incident waves, with the aim to restore non-line-of-sight communication links. Composed of elementary scatterers, the RIS has been so far treated as a collection of point scatterers with properties similar to antennas in an equivalent massive MIMO communication link. Despite the discrete nature of the RIS, current design approaches often treat the RIS as a continuous radiating surface, which is… 

Figures from this paper

References

SHOWING 1-10 OF 43 REFERENCES
Analytical Performance Assessment of Beamforming Efficiency in Reconfigurable Intelligent Surface-Aided Links
TLDR
It is shown that, contrary to typical line-of-sight links, the increase of the transmitter gain does not always guarantee power increase at the receiver, even for an infinitely large RIS, and how the RIS size can further affect the received power is explained.
Analytical Modeling of the Path-Loss for Reconfigurable Intelligent Surfaces – Anomalous Mirror or Scatterer ?
TLDR
This work introduces simple formulas for the electric field scattered by an RIS that is modeled as a sheet of electromagnetic material of negligible thickness by leveraging the general scalar theory of diffraction and the Huygens-Fresnel principle.
Path Loss in Reconfigurable Intelligent Surface-Enabled Channels
  • S. Ellingson
  • Computer Science
    2021 IEEE 32nd Annual International Symposium on Personal, Indoor and Mobile Radio Communications (PIMRC)
  • 2021
TLDR
This model is used to further elucidate the matter of path loss of the RIS-enabled channel relative to that of the free space direct and specular reflection channels, which is an important consideration in the design of networks employing RIS technology.
Wireless Communications With Reconfigurable Intelligent Surface: Path Loss Modeling and Experimental Measurement
TLDR
The proposed models, which are first validated through extensive simulation results, reveal the relationships between the free-space path loss of RIS-assisted wireless communications and the distances from the transmitter/receiver to the RIS, the size of the ris, the near-field/far-field effects of the RIS and the radiation patterns of antennas and unit cells.
Smart Radio Environments Empowered by Reconfigurable Intelligent Surfaces: How It Works, State of Research, and The Road Ahead
TLDR
The emerging research field of RIS-empowered SREs is introduced; the most suitable applications of RISs in wireless networks are overviewed; an electromagnetic-based communication-theoretic framework for analyzing and optimizing metamaterial-based RISs is presented; and the most important research issues to tackle are discussed.
Impact of Reconfigurable Intelligent Surface size on beamforming efficiency
TLDR
This paper shows that there is an interplay between the transmitter beamwidth and the RIS size that leads to a maximum power at the receiver.
A Communication Model for Large Intelligent Surfaces
TLDR
The purpose of this paper is to introduce a communication model for Large Intelligent Surfaces (LIS) as a collection of tiny closely spaced antenna elements, and gives the expression of the mutual coupling for two types of planar arrays.
Communication Models for Reconfigurable Intelligent Surfaces: From Surface Electromagnetics to Wireless Networks Optimization
TLDR
This tutorial paper focuses on communication models for RISs that are based on inhomogeneous sheets of surface impedance, and offers a step-by-step tutorial on formulating electromagnetically-consistent analytical models for optimizing the surface impedance.
Reconfigurable Intelligent Surface-Based Wireless Communications: Antenna Design, Prototyping, and Experimental Results
TLDR
A new type of high-gain yet low-cost RIS that bears 256 elements that combines the functions of phase shift and radiation together on an electromagnetic surface, where positive intrinsic-negative (PIN) diodes are used to realize 2-bit phase shifting for beamforming.
Reconfigurable Intelligent Surface Optimal Placement in Millimeter-Wave Networks
TLDR
A novel system model is presented that takes into account the relationship between the transmission beam footprint at the RIS plane and the RIS size and derives the end-to-end expression of the received signal power and approximate closed-form expressions.
...
...