Vanadium Dioxide-Based Ultra-reconfigurable Intelligent Reflective Surfaces

Authors

Randy Matos, Florida International UniversityFollow

Document Type

Dissertation

Degree

Doctor of Philosophy (PhD)

Major/Program

Electrical and Computer Engineering

First Advisor's Name

Nezih Pala

First Advisor's Committee Title

Committee Chair

Second Advisor's Name

Stavros Georgakopoulos

Second Advisor's Committee Title

Committee member

Third Advisor's Name

Chunlei Wang

Third Advisor's Committee Title

Committee member

Fourth Advisor's Name

Deidra Hodges

Fourth Advisor's Committee Title

Committee member

Fifth Advisor's Name

Oscar Ares Muzio

Fifth Advisor's Committee Title

Committee member

Sixth Advisor's Name

Shubhendu Bhardwaj

Sixth Advisor's Committee Title

Committee member

Keywords

electrical and electronics, electronics and photonics, other materials science and engineering, systems and communications

Date of Defense

6-30-2023

Abstract

5G technologies are the current state of the art in wireless telecommunications and operate within the 450 MHz and 52 GHz range. However, ever increasing demands for data rates in wireless communications have placed tremendous burden on existing technologies and system designers. Recent advancements in reconfigurable intelligent surfaces (RIS) have introduced the possibility of controlling the scattering and reflection of wireless signals, thereby mitigating the negative effects of the propagation medium. RIS technology enables effective control of the wavefront by manipulating the phase, amplitude, frequency, and even polarization of the impinging signals, eliminating the need for complex decoding, encoding, and radio frequency processing operations. In this thesis, a VO₂-based intelligent reflective surface is proposed and studied both theoretically and experimentally.

First, we performed a detailed study on the viability of the VO₂-based device. Thermal and electromagnetic properties were rigorously studied to determine material limits and device performance. For the first time, a VO₂-based device using a continuous film was demonstrated that could be used as an intelligent reflective surface. The reflection properties of VO₂ thin films on sapphire was experimentally verified. Then, by adapting this device to standard reflectarray technologies, we showed EM wave reflection and beam steering with the possibility of real-time reconfiguration of the reflection surface.

Here we present the fundamental work to enable a VO₂-based ultra-reconfigurable intelligent surface used to manipulate electromagnetic waves in the 5G spectrum. The experimentally verified VO₂ thin films showcased reflection bandwidth of >300º. This bandwidth is achievable without being beholden to one, or very few limited reflection states, which is a common limitation of current reflectarray systems. It has no need for mechanical intervention and can achieve reconfigurability using only electrical stimulation. This device would be a first of its kind in the field and could enable smart radio environments for the increasing demand in telecommunications.

Identifier

FIDC011164

ORCID

0000-0003-2942-8628

Recommended Citation

Matos, Randy, "Vanadium Dioxide-Based Ultra-reconfigurable Intelligent Reflective Surfaces" (2023). FIU Electronic Theses and Dissertations. 5411.
https://digitalcommons.fiu.edu/etd/5411