SRE aims at:

  • Deep physical understanding, design tools, implementation and assessment of smart electromagnetic nodes for smart radio environments (SREs). In particular: metamaterials, reconfigurable intelligent surfaces, smart skins, smart antennas, active repeaters, energy harvesting solutions, signal processing algorithms for communication and sensing.
  • Demonstration of lab-scale SREs for well-defined use cases.
  • Meet the KPIs for 6G wireless systems through reduced complexity, cost effective, energy effective, environmentally friendly and green solutions.

SRE is part of Spoke 7 – Green and Smart Environments

Project PIs: Davide Dardari / Daniele Riccio

[M1-M15]

Metasurface Design: Designed fractal-based metasurfaces and a plasma-based reconfigurable intelligent surface (RIS) for beam-steering. Developed a ray-tracing tool for SRE planning and investigated curved passive smart skins for urban infrastructures.

Smart Skins: A smart skin to be mounted on poles using resonant type unit cells has been designed to extend the coverage. 

Energy Harvesting: Designed innovative schemes to achieve energy-autonomous RIS.

RIS-Aided Communications: Developed algorithms for optimal RIS configuration and improved communication performance. Low-complexity channel estimation schemes have been designed. 

RIS-Aided Localization: Exploitation of frequency-selective metasurfaces for localization and sensing in non-line-of-sight conditions, achieving centimeter-level accuracy. We also formulated performance limits for vehicular applications.

Imaging: Explored advanced imaging techniques for customizing electromagnetic field reflection ( “see” beyond the corner”).

[M16-M24]

Metasurface technologies and design:
  • An activity to design efficient methods for computational EM, including novel basis functions for finite-elements and boundary-elements computational methods, is undertaken. In this direction, connection with machine learning has been considered. In addition, an effective and efficient synthesis strategy has been set up. It is based on an accurate radiative model and is able to deal with a large number of reflecting elements, each one characterized by more than one control parameter. The porting on GPU architecture is currently under evaluation. A new research activity started to effectively represent the field radiated/scattered by oblong objects.
  • Significant progress has been obtained in overcoming the key challenges related to the design and optimization of reconfigurable intelligent surfaces (RIS) and the accurate modeling of electromagnetic field scattering. The work has demonstrated the potential to alter the direction of reflected electromagnetic fields by selecting appropriate smart material inclusions and constructing highly efficient RIS.
  • The activity on the design of smart skins working in reflection or transmission mode and discretized with almost resonant unit cells has been continued. A more detailed and accurate modeling of frequency-selective metasurfaces has been investigated and validated through EM tools.
  • The realistic design of a plasma-based reflecting surface is ongoing. The surface is capable of beam-steering relying on a 1-bit control strategy of the plasma density.
  • A dedicated tool for the analysis of quasi-periodic arrays with cylindrical inclusions has been developed. Applications cover a quite large range of possible devices, including filters, RIS, dichroics mirrors, and arrays of antennas.
Channel models
  • The activity focused on the experimental validation of the effect of an interferer on an indoor communication system supported by a RIS, concentrating on the unlicensed 60 GHz ISM band by using a realistic 3D channel model of an office to implement a digital twin-based technique. The design of the codebook to be used by an RIS in the sub-6GHz band has started.
  • The developed bilateral RIS model to be included in Ray-tracing tools has also been designed for use in outdoor environments (building facades) to improve coverage from outdoor to indoor, particularly at higher frequencies where Building Penetration Loss can result in significant attenuation, leading to poor indoor coverage and degraded Quality of Service (QoS)
Energy harvesting technologies for energy-autonomous EM systems:
  • The solutions designed for efficient power conversions and reflective metasurface are under validation through transistor-level and full-wave/nonlinear co-simulations. The design of the converter in a 22-nm CMOS technology has been started,
RIS-Aided Channel Estimation and Communication:
  • As a follow-up of the activity done on the optimization of the RIS configuration, an approach aiming to determine the optimal configuration of diagonal and beyond-diagonal RISs has been proposed based on the optimal configuration of the fully connected RIS.
  • Stacked intelligent surfaces (SIM) and their extension have been studied by combining nearly passive layers with phase-only reconfiguration capabilities and active layers integrated with amplifier chips to enable amplitude control. Extensive simulations have been carried out to demonstrate that this solution significantly enhances capacity compared to previously reported phase-only coding SIM.
Sensing and Localization:
  • A novel sensing system has been proposed whereby a source in motion aims at imaging a region of interest in non-line-of-sight (NLOS) using a properly configured static passive metasurface.
  • Monostatic sensing solutions have also been investigated to exploit near-field propagation characteristics to estimate a moving target's speed components. Theoretical fundamental limits have been derived.
  • On the radar microwave imaging side for targets in indoor environments, a linear tomographic reconstruction approach at a single frequency was considered, and a theoretical analysis was conducted to investigate the effect of multipath propagation on achievable imaging capabilities.
Proofs-of-Concept (PoCs):
  • The activity related to the four identified proofs-of-concept, corresponding to different use cases such as industrial environments and coverage extension of mmWave cellular networks, is continuing through the design of the components composing them.
Main outcomes for potential exploitation:
Metaprisms for enhanced communication and sensing: The innovation consists of a fully passive frequency-selective, and non-reconfigurable metasurface, named metaprism, and related signal processing schemes, aimed to assist the wireless connectivity, reliability, throughput, and localization in complex indoor environments, with a low-cost, zero-latency, full-duplex, low-complexity, and green technology (zero-consumption, zero-EM emission and no maintenance).

In contrast to other solutions, one of the main features of metaprisms is recycling the radio waves in a constructive and energy-efficient manner. From a socio-economic point of view, this is a promising solution to lower the levels of EM radiations in sensitive environments, such as hospitals and airplanes. One of the main advantages of the proposed metaprism technology lies in the fact that it does not require high resources and very expensive equipment to be implemented, thus lowering the economic entry barrier and making it accessible to small and medium enterprises (SMEs).

Efficient low complexity channel estimation and tracking methods in RIS-aided communication at mmWaves.
The reliability for 6G radio environment and sensor localisation is achieved by exploiting the adaptive reconfigurability of RISs to tackle the dead-zone problem in challenging scenarios.

Societal Impact:
Enhanced 5G and Beyond connectivity through optimized RIS selection can significantly improve communication in smart radio environments. Improved connectivity can enhance social inclusion and bridge the digital divide, providing more people with access to critical services and opportunities. Possibility of enhancing user communication performance by exploiting location information. This leads to a smarter use of the existing communication resources. For example, user tracking can enable more responsive and personalized services, improving quality of life and operational efficiency or real-time monitoring for safer factories and the support to the activity of human operators.

Economic Impact:
Using less expensive RISs with a limited number of quantization bits for their phase profiles can make advanced communication technologies more affordable. This cost efficiency can encourage broader adoption of RIS technology in various industries, from telecommunications to automotive and beyond. Re-use of the existing communication infrastructure for tracking and localization services leading to a reduced cost and hardware deployment. Possibility of optimizing the RISs less frequently with the same level of tracking/localization accuracy.

Scientific outcomes:
  • 87 Publications
  • 1 Patent + 1 Innovation
  • 3 Best Paper Award
  • 11 Invited talks
  • 12 Workshops/special sessions


Papers:
M. A. Shameli, M. Magarotto, A.-D. Capobianco, L. Schenato, M. Santagiustina, M. Vincenti, D. De Ceglia, “Reconfigurable and Broadband Analog Computing With Terahertz Metasurface Based on Electrical Tuning of Vanadium-Dioxide Resonators”, IEEE Access, vol.12, pp. 170478-170486, November 2024

M. Haghshenas, P. Ramezani, M. Magarini, E. Björnson, “Parametric channel estimation with short pilots in RIS-assisted near-and far-field communications,” IEEE Transactions on Wireless Communications, Vol. 23, No. 8, pp. 10366 - 10382, August 2024

D. Dardari, "Reconfigurable Electromagnetic Environments: A General Framework," in IEEE Journal on Selected Areas in Communications, vol. 42, no. 6, pp. 1479-1493, June 2024
An interaction took place with the industrial partner Leonardo s.p.a. for the study and development of universal metasurface antennas (UMA) for simultaneous and independent controls of all the properties of electromagnetic waves in a software-defined manner.

UMA-based transceivers might implement a form of hybrid A/D beamforming, since part  of the processing of the transmitted/received signals is carried out in the analog domain. UMA provides similar beamforming capabilities to those achievable with typical phased array antennas, but with much lower power consumption and cost. In addition, Leonardo has shown keen interest in plasma antenna technology.

Several meetings have been conducted to explore the potential of this technology and to evaluate the state-of-the-art solutions for plasma generation, identifying the pros and cons of various approaches. There is particular interest in the potential use of plasma to enhance the performance of current radomes.

Plasma can be toggled on and off to create selective screens, which minimize interference among antennas. The most promising application for these selective plasma screens appears to be in shipborne antennas for satellite communications.

Interactions with other companies are ongoing.
Reconfigurable intelligent surfaces (RISs) represent the most promising Key Enabling Technology candidate to take on the challenges of 6G systems in terms of dramatically reduced latency and ultra-high capacity.

The project S12 – SRE proposes new key-enabling technologies for the realization of smart radio environments based on reconfigurable intelligent metasurfaces to overcome the current limitations of 5G technologies in order to handle ultra-high capacity, near-zero latency, and high energy efficiency.

The project aims to combine the strong expertise of groups in Italy working in the fields of wireless communication and electromagnetic theory, with the goal of exploring this new technology and making it suitable for enabling the new paradigm of smart radio environments, allowing the Country to play a relevant role in Europe and worldwide in the communications of the future.

The main outcomes achieved so far can be summarized as follows:
  • Innovative metasurface design approaches for the implementation of RIS, even energy autonomous.
  • Algorithms for optimal RIS configuration and novel metasurface-based approaches for improved communication performance in terms of coverage, data rate, reduced latency, and energy consumption.
  • RIS-Aided Localization and imaging: New solutions exploiting passive frequency-selective metasurfaces for localization and sensing in non-line-of-sight conditions, achieving centimeter-level accuracy.
Publications
  • Expected: at least 60 publications in 36 months
  • Accomplished: 87
  • Readiness Level: 146%
Joint publications (at least two partners of RESTART)
  • Expected: >=30% joint publications in 36 months
  • Accomplished: 15/87
  • Readiness Level: 17%
Talks/Keynotes/Communication Events
  • Expected: 20 talks within SRE activities in 36 months
  • Accomplished: 11 (among dissemination events and conference presentations)
  • Readiness Level: 84%
Organization of workshops/special sessions/webinars
  • Expected: 10 events chairing/organizing within SRE activities in 36 months
  • Accomplished: 12
  • Readiness Level: 140%
Meetings/presentations with/to companies:
  • Expected: 10
  • Accomplished: 4
  • Readiness Level: 40%
Patents/Innovations
  • Expected: 10 items over 36 months
  • Accomplished: 2 (1 patent, 1 innovation)
  • Readiness Level: 30%
Demo/Poc
  • Expected: at least 4 PoCs expected by the end of the project
  • Accomplished: 0 (4 in preparation)
  • Readiness Level: 0% 
Project Meetings
  • Expected: > 30 meetings
  • Accomplished: 28 meetings
  • Readiness: 93%
Open-source contributions
  • Expected: at least one expected by the end of the project
  • Accomplished: 0
  • Readiness Level: 0% 
Standardization contributions
  • Expected: none
  • Accomplished: 0
  • Readiness Level: N/A
Identifying the state of the art of the latest applications of 6G in telemedicine services. D1: Passive smart EM nodes - Initial report
  • Due date: 30/6/2023
  • Status: Accomplished
  • Readiness level: 100%
D2: Communications, localization, and sensing in SREs - Initial report
  • Due date: 30/6/2023
  • Status: Accomplished
  • Readiness level: 100%
D3: First report on dissemination activities
  • Due date: 31/12/2023
  • Status: Accomplished
  • Readiness level: 100%
D4: Modeling and design of Smart Radio Environments - Intermediate report
  • Due date: 31/3/2024
  • Status: Accomplished
  • Readiness level: 100%
D5: Proof of concept and performance evaluation - Intermediate report
  • Due date: 30/6/2024
  • Status: Accomplished
  • Readiness level: 100%
D6: Passive smart EM nodes - Intermediate report
  • Due date: 30/6/2024
  • Status: Accomplished
  • Readiness level: 100%
D7: Communications, localization, and sensing in SREs - Intermediate report
  • Due date: 30/9/2024
  • Status: Expected
  • Readiness level: 100%
D8: Second report on dissemination, communication, and technology transfer
  • Due date: 31/12/2024
  • Status: Expected
  • Readiness level: 100%
D9: Modeling and design of Smart Radio Environments - Final report
  • Due date: 30/6/2025
  • Status: Expected
  • Readiness level: 30%
D10: Passive smart EM nodes - Final report
  • Due date: 30/11/2025
  • Status: Expected
  • Readiness level: 0%
D11: Active smart EM nodes: smart repeaters and integrated access & backhauling nodes - Final report
  • Due date: 30/11/2025
  • Status: Expected
  • Readiness level: 0%
D12: Communications, localization, and sensing in SREs - Final report
  • Due date: 31/12/2025
  • Status: Expected
  • Readiness level: 0%
D13: Proof of concept and performance evaluation - Final report
  • Due date: 31/12/2025
  • Status: Expected
  • Readiness level: 0%
D14: Final report on dissemination, communication, and technology transfer
  • Due date: 31/12/2025
  • Status: Expected
  • Readiness level: 0%

Researchers involved: about 200 PM

Collaboration proposals:
The team could benefit from collaborating with healthcare facilities employing telemedicine services in their clinical routing.
For any proposal of collaboration within the project please contact the project PIs.


SRE News: