Publications (43)
Channel Estimation in MIMO Systems Aided by Microwave Linear Analog Computers (MiLACs)
Qiaosen Zhang, Matteo Nerini, Bruno Clerckx
Microwave linear analog computers (MiLACs) have recently emerged as a promising solution for future gigantic multiple-input multiple-output (MIMO) systems, enabling beamforming wit…
5G Network Slicing for Wi-Fi Networks
Matteo Nerini, David Palma
Future networks will pave the way for a myriad of applications with different requirements and Wi-Fi will play an important role in local area networks. This is why network slicing…
RIS Optimization and Scaling Laws in Multi-Operator Systems: Is Quadratic Scaling Achievable?
Zheyu Wu, Matteo Nerini, Bruno Clerckx
This paper studies multi-operator wireless communication systems aided by general reconfigurable intelligent surface (RIS), including both conventional single-connected RIS and bey…
Microwave Linear Analog Computers (MiLACs) for Communications: Opportunities and Challenges
Matteo Nerini, Bruno Clerckx
Future wireless systems will require ever larger antenna arrays and heavier signal processing, making conventional digital multiple-input multiple-output (MIMO) architectures diffi…
Physics-Compliant Modeling and Scaling Laws of Multi-RIS Aided MIMO Systems
Matteo Nerini, Gabriele Gradoni, Bruno Clerckx
Reconfigurable intelligent surface (RIS) enables the control of wireless channels to improve coverage. To further extend coverage, multi-RIS aided systems have been explored, where…
Channel Estimation and Beamforming for Microwave Linear Analog Computers (MiLACs)-Aided Multiuser MISO Systems
Qiaosen Zhang, Matteo Nerini, Bruno Clerckx
Microwave linear analog computers (MiLACs) have recently gained attention for future gigantic multiple-input multiple-output (MIMO) systems by enabling beamforming with greatly red…
Low-Complexity Planar Beyond-Diagonal RIS Architecture Design Using Graph Theory
Matteo Nerini, Zheyu Wu, Shanpu Shen +1
Reconfigurable intelligent surfaces (RISs) enable programmable control of the wireless propagation environment and are key enablers for future networks. Beyond-diagonal RIS (BD-RIS…
Dual-Polarized Beyond Diagonal RIS
Matteo Nerini, Bruno Clerckx
Beyond diagonal reconfigurable intelligent surface (BD-RIS) is a family of RIS architectures more flexible than conventional RIS. While BD-RIS has been primarily analyzed assuming…
Beyond Diagonal Reconfigurable Intelligent Surfaces with Mutual Coupling: Modeling and Optimization
Hongyu Li, Shanpu Shen, Matteo Nerini +2
This work studies the modeling and optimization of beyond diagonal reconfigurable intelligent surface (BD-RIS) aided wireless communication systems in the presence of mutual coupli…
Enabling Smart Radio Environments in the Frequency Domain With Movable Signals
Matteo Nerini, Bruno Clerckx
Smart radio environments (SREs) enhance wireless communications by allowing control over the channel. They have been enabled through surfaces with reconfigurable electromagnetic (E…
Physics-Compliant Modeling and Optimization of MIMO Systems Aided by Microwave Linear Analog Computers
Matteo Nerini, Bruno Clerckx
Microwave linear analog computer (MiLAC) has emerged as a promising architecture for implementing linear multiple-input multiple-output (MIMO) processing in the analog domain, with…
Beyond-Diagonal RIS Prototype and Performance Evaluation
Jean Tapie, Matteo Nerini, Bruno Clerckx +1
We present the first experimental prototype of a reflective beyond-diagonal reconfigurable intelligent surface (BD-RIS), i.e., a RIS with reconfigurable inter-element connections.…
Closed-Form Global Optimization of Beyond Diagonal Reconfigurable Intelligent Surfaces
Matteo Nerini, Shanpu Shen, Bruno Clerckx
Reconfigurable intelligent surfaces (RISs) allow controlling the propagation environment in wireless networks by tuning multiple reflecting elements. RISs have been traditionally r…
Learning Representations for CSI Adaptive Quantization and Feedback
Valentina Rizzello, Matteo Nerini, Michael Joham +2
In this work, we propose an efficient method for channel state information (CSI) adaptive quantization and feedback in frequency division duplexing (FDD) systems. Existing works ma…
Static Grouping Strategy Design for Beyond Diagonal Reconfigurable Intelligent Surfaces
Matteo Nerini, Shanpu Shen, Bruno Clerckx
Beyond diagonal reconfigurable intelligent surface (BD-RIS) extends conventional RIS through novel architectures, such as group-connected RIS, with scattering matrix not restricted…
T-Parameters Based Modeling for Stacked Intelligent Metasurfaces: Tractable and Physically Consistent Model
Hamad Yahya, Matteo Nerini, Bruno Clerckx +1
This work develops a physically consistent model for stacked intelligent metasurfaces (SIM) using multiport network theory and transfer scattering parameters (T-parameters). Unlike…
Global Optimal Closed-Form Solutions for Intelligent Surfaces With Mutual Coupling: Is Mutual Coupling Detrimental or Beneficial?
Matteo Nerini, Hongyu Li, Bruno Clerckx
Reconfigurable Intelligent Surface (RIS) is a breakthrough technology enabling the dynamic control of the propagation environment in wireless communications through programmable su…
Analog Computing with Hybrid Couplers and Phase Shifters
Matteo Nerini, Xuekang Liu, Bruno Clerckx
Analog computing with microwave signals can enable exceptionally fast computations, potentially surpassing the limits of conventional digital computing. For example, by letting som…
Beyond-Diagonal RIS Architecture Design and Optimization under Physics-Consistent Models
Zheyu Wu, Matteo Nerini, Bruno Clerckx
Reconfigurable intelligent surface (RIS) is a promising technology for future wireless communication systems. Conventional RIS is constrained to a diagonal scattering matrix, which…
Microwave Linear Analog Computer (MiLAC)-aided Multiuser MISO: Fundamental Limits and Beamforming Design
Zheyu Wu, Matteo Nerini, Bruno Clerckx
As wireless communication systems evolve toward the 6G era, ultra-massive/gigantic MIMO is envisioned as a key enabling technology. Recently, microwave linear analog computer (MiLA…
Physically Consistent Modeling of Stacked Intelligent Metasurfaces Implemented with Beyond Diagonal RIS
Matteo Nerini, Bruno Clerckx
Stacked intelligent metasurface (SIM) has emerged as a technology enabling wave domain beamforming through multiple stacked reconfigurable intelligent surfaces (RISs). SIM has been…
Beyond Diagonal Reconfigurable Intelligent Surfaces Utilizing Graph Theory: Modeling, Architecture Design, and Optimization
Matteo Nerini, Shanpu Shen, Hongyu Li +1
Recently, beyond diagonal reconfigurable intelligent surface (BD-RIS) has been proposed to generalize conventional RIS. BD-RIS has a scattering matrix that is not restricted to bei…
Capacity of Two-User Wireless Systems Aided by Movable Signals
Matteo Nerini, Bruno Clerckx
Movable signals have emerged as a third approach to enable smart radio environments (SREs), complementing reconfigurable intelligent surfaces (RISs) and flexible antennas. This pap…
Active Beyond-Diagonal Reconfigurable Intelligent Surfaces: Modeling, Architecture Design, and Optimization
Shanpu Shen, Hongyu Li, Matteo Nerini +2
Beyond-diagonal reconfigurable intelligent surfaces (BD-RISs) are an emerging RIS 2.0 technology for future wireless communication. However, BD-RISs are primarily passive without a…
Analog Computing for Signal Processing and Communications -- Part I: Computing with Microwave Networks
Matteo Nerini, Bruno Clerckx
Analog computing has been recently revived due to its potential for energy-efficient and highly parallel computations. In this two-part paper, we explore analog computers that line…
A Universal Framework for Multiport Network Analysis of Reconfigurable Intelligent Surfaces
Matteo Nerini, Shanpu Shen, Hongyu Li +2
Reconfigurable intelligent surface (RIS) is an emerging paradigm able to control the propagation environment in wireless systems. Most of the research on RIS has been dedicated to…
Movable Beyond-Diagonal Reconfigurable Intelligent Surfaces: Moving, Interconnecting, or Both?
Shuyue Xu, Matteo Nerini, Bruno Clerckx
This letter proposes a movable beyond-diagonal reconfigurable intelligent surfaces (MA-BD-RIS) design, combining inter-element connectivity and movability for channel enhancement.…
A Tutorial on Beyond-Diagonal Reconfigurable Intelligent Surfaces: Modeling, Architectures, System Design and Optimization, and Applications
Hongyu Li, Matteo Nerini, Shanpu Shen +1
Written by its inventors, this first tutorial on Beyond-Diagonal Reconfigurable Intelligent Surfaces (BD-RISs) provides the readers with the basics and fundamental tools necessary…
Wideband Modeling and Beamforming for Beyond Diagonal Reconfigurable Intelligent Surfaces
Hongyu Li, Matteo Nerini, Shanpu Shen +1
This work studies the wideband modeling and beamforming design of beyond diagonal reconfigurable intelligent surface (BD-RIS), which generalizes and goes beyond conventional RIS wi…
MIMO Systems Aided by Microwave Linear Analog Computers: Capacity-Achieving Architectures with Reduced Circuit Complexity
Matteo Nerini, Bruno Clerckx
To meet the demands of future wireless networks, antenna arrays must scale from massive multiple-input multiple-output (MIMO) to gigantic MIMO, involving even larger numbers of ant…
Beyond Diagonal RIS: Passive Maximum Ratio Transmission and Interference Nulling Enabler
Hamad Yahya, Hongyu Li, Matteo Nerini +2
Beyond diagonal reconfigurable intelligent surfaces (BD-RIS) generalizes and goes beyond conventional diagonal reconfigurable intelligent surfaces (D-RIS) by interconnecting elemen…
Beyond Diagonal Reconfigurable Intelligent Surfaces in Wideband OFDM Communications: Circuit-Based Modeling and Optimization
Hongyu Li, Matteo Nerini, Shanpu Shen +1
This work investigates the modeling and optimization of beyond diagonal reconfigurable intelligent surface (BD-RIS), which generalizes conventional RIS with diagonal phase shift ma…
Pareto Frontier for the Performance-Complexity Trade-off in Beyond Diagonal Reconfigurable Intelligent Surfaces
Matteo Nerini, Bruno Clerckx
Reconfigurable intelligent surface (RIS) is an emerging technology allowing to control the propagation environment in wireless communications. Recently, beyond diagonal RIS (BD-RIS…
Microwave Linear Analog Computer (MiLAC) for Simultaneous Active and Passive Beamforming
Matteo Nerini, Bruno Clerckx
Microwave linear analog computers (MiLACs) have recently emerged to enable high-performance and efficient beamforming in the analog domain. In this paper, we introduce a dual-funct…
Capacity of MIMO Systems Aided by Microwave Linear Analog Computers (MiLACs)
Matteo Nerini, Bruno Clerckx
Future wireless systems, known as gigantic multiple-input multiple-output (MIMO), are expected to enhance performance by significantly increasing the number of antennas, e.g., a fe…
Machine Learning-Based CSI Feedback With Variable Length in FDD Massive MIMO
Matteo Nerini, Valentina Rizzello, Michael Joham +2
To fully unlock the benefits of multiple-input multiple-output (MIMO) networks, downlink channel state information (CSI) is required at the base station (BS). In frequency division…
Overhead-Free Blockage Detection and Precoding Through Physics-Based Graph Neural Networks: LIDAR Data Meets Ray Tracing
Matteo Nerini, Bruno Clerckx
In this letter, we address blockage detection and precoder design for multiple-input multiple-output (MIMO) links, without communication overhead required. Blockage detection is ac…
Analog Computing for Signal Processing and Communications -- Part II: Toward Gigantic MIMO Beamforming
Matteo Nerini, Bruno Clerckx
Analog-domain operations offer a promising solution to accelerating signal processing and enabling future multiple-input multiple-output (MIMO) communications with thousands of ant…
Movable Signals with Dual-Polarized Fixed Intelligent Surfaces: Beyond Diagonal Reflection Matrices
Matteo Nerini, Bruno Clerckx
This paper investigates wireless systems aided by dual-polarized intelligent surfaces. We compare reconfigurable intelligent surface (RIS), which adjust their reflection matrices,…
Localized and Distributed Beyond Diagonal Reconfigurable Intelligent Surfaces with Lossy Interconnections: Modeling and Optimization
Matteo Nerini, Golsa Ghiaasi, Bruno Clerckx
Reconfigurable intelligent surface (RIS) is a key technology to control the communication environment in future wireless networks. Recently, beyond diagonal RIS (BD-RIS) emerged as…
Physics-Compliant Modeling and Scaling Laws of Multi-RIS Aided Systems
Matteo Nerini, Gabriele Gradoni, Bruno Clerckx
Reconfigurable intelligent surface (RIS) is a revolutionary technology enabling the control of wireless channels and improving coverage in wireless networks. To further extend cove…
Discrete-Value Group and Fully Connected Architectures for Beyond Diagonal Reconfigurable Intelligent Surfaces
Matteo Nerini, Shanpu Shen, Bruno Clerckx
Reconfigurable intelligent surfaces (RISs) allow controlling the propagation environment in wireless networks through reconfigurable elements. Recently, beyond diagonal RISs (BD-RI…
Reconfigurable Intelligent Surfaces 2.0: Beyond Diagonal Phase Shift Matrices
Hongyu Li, Shanpu Shen, Matteo Nerini +1
Reconfigurable intelligent surface (RIS) has been envisioned as a promising technique to enable and enhance future wireless communications due to its potential to engineer the wire…