11 papers
Discrete Morse Theory for Computing Filtered Cosheaf Homology
Neria Baris
This paper addresses the computation of persistent homology for filtrations of cellular cosheaves over a fixed cell complex, where the algebraic data vary along the filtration whil…
SIM-Aided Near-Field Channel and Localization Estimation With Dimensionality Reduction: A Multiport Network Theory Approach
Andrea Abrardo, Bartoli Giulio
The deployment of Extremely Large-Scale Antenna Arrays for 6G enables radiative near-field sensing but poses significant challenges in terms of hardware complexity and interference…
Stacked Intelligent Metasurfaces (SIM) in the Nonlinear Regime: A Multiport Network Model Approach
Andrea Abrardo, Alberto Toccafondi
We present a physically consistent multiport framework for stacked intelligent metasurfaces (SIMs) with linear and explicit nonlinear terminations. The model provides closed-form i…
From Multi-Port Models to Cascade Structures: Optimization of Active Unilateral Stacked Intelligent Metasurfaces
Andrea Abrardo, Giulio Bartoli, Marco Di Renzo +1
This paper develops a multi-port S-parameter framework for the analysis and optimization of stacked intelligent metasurfaces (SIMs) with unilateral active interconnections. By mode…
Modeling, Optimization and Electromagnetic Validation of Stacked Intelligent Metasurfaces by Using a Multiport Network Model
Giuseppe Pettanice, Andrea Abrardo, Alberto Toccafondi +1
Stacked intelligent metasurfaces (SIMs) extend the concept of reconfigurable intelligent surfaces by cascading multiple programmable layers, enabling advanced electromagnetic wave…
Metaprism Design for Wireless Communications: Angle-Frequency Analysis, Physical Realizability Constraints, and Performance Optimization
Silvia Palmucci, Andrea Abrardo, Davide Dardari +2
Recent advancements in smart radio environment technologies aim to enhance wireless network performance through the use of low-cost electromagnetic (EM) devices. Among these, recon…
A Novel Comprehensive Multiport Network Model for Stacked Intelligent Metasurfaces (SIM) Characterization and Optimization
Andrea Abrardo, Giulio Bartoli, Alberto Toccafondi
Reconfigurable Intelligent Surfaces (RIS) represent transformative technologies for next-generation wireless communications, offering advanced control over electromagnetic wave pro…
RIS-Aided Covert Communications with Statistical CSI: A Multiport Network Theory Approach
Andrea Abrardo, Giulio Bartoli
A novel framework for covert communications aided by Reconfigurable Intelligent Surfaces (RIS) is proposed. In this general framework, the use of multiport network theory for model…
Power Minimization with Rate Constraints for Multi-User MIMO Systems with Large-Size RISs
Silvia Palmucci, Giulio Bartoli, Andrea Abrardo +2
This study focuses on the optimization of a single-cell multi-user multiple-input multiple-output (MIMO) system with multiple large-size reconfigurable intelligent surfaces (RISs).…
CSI-Free Optimization of Reconfigurable Intelligent Surfaces with Interference by Using Multiport Network Theory
A. Abrardo
Reconfigurable Intelligent Surfaces (RIS) will play a pivotal role in next-generation wireless systems. Despite efforts to minimize pilot overhead associated with channel estimatio…
Design of Reconfigurable Intelligent Surfaces by Using S-Parameter Multiport Network Theory -- Optimization and Full-Wave Validation
Andrea Abrardo, Alberto Toccafondi, Marco Di Renzo
Multiport network theory has been proved to be a suitable abstraction model for analyzing and optimizing reconfigurable intelligent surfaces (RISs) in an electromagnetically consis…