Titolo della tesi: Innovative Multifunctional Electromagnetic Shielding Technologies for Reducing Electromagnetic Impact in Satellite and Sensor Network-Application
The increasing demands for advanced satellite and sensor network applications, alongside the need for improved stealth capabilities in aerospace and defense sectors, have driven significant research into multifunctional materials for electromagnetic (EM) shielding and absorption. This thesis presents a comprehensive study of innovative electromagnetic absorbers and shielding structures, addressing the challenges of modern communication systems and low observability technologies.
The research is divided into three key areas. The first part investigates the development of a multifunctional Sensing and Electromagnetic Absorbing Laminate (SEAL) that integrates piezoresistive sensor arrays with nanostructured coatings to combine electromagnetic interference (EMI) absorption with structural health monitoring (SHM). The SEAL offers a lightweight, multifunctional solution tailored for aeronautical applications. Additionally, a Broadband Radar Absorbing Structure (B-RAS) optimized for the 4–20 GHz frequency range is developed using graphene nanoplatelets (GNPs)-filled polyurethane paints. This absorber achieves broad frequency absorption with minimal structural impact, ideal for stealth applications in the defense sector.
The second part of the thesis focuses on Single-Layer Insulated (SLI) and Multi-Layer Insulated (MLI) materials used for EM shielding in aerospace applications. Experimental characterization and numerical simulations were employed to assess the shielding effectiveness (SE) of both planar and embossed SLI materials, as well as simplified MLI structures. The results revealed that while SLI materials provide strong baseline SE performance, the layered structure of MLI materials, especially when incorporating air gaps through embossing, significantly enhances SE. These findings highlight the importance of material design and geometrical modifications in optimizing SE for lightweight shielding applications.
The third part of the thesis explores the use of periodic structures such as metasurfaces and High-Impedance Surfaces (HIS) for electromagnetic shielding and absorption. Analytical models for the effective inductance and capacitance of periodic metal patches and wire grids were developed and validated through full-wave simulations. Additionally, HIS-based microwave absorbers were designed to optimize absorption by controlling substrate properties and patch configurations, providing effective shielding and absorption across a range of incidence angles and polarization states.
Overall, this thesis provides valuable insights into the design, fabrication, and optimization of multifunctional materials for electromagnetic absorbers and shielding. The findings contribute to the advancement of technologies used in satellite applications and sensor networks, laying the groundwork for further exploration into material synthesis, complex geometries, and enhanced electromagnetic performance.