1,721,228 research outputs found
Hybrid MFIE/FDTD analysis of the shielding effectiveness of a composite enclosure excited by a transient plane wave
No full textA combined magnetic field integral equation (MFIE) and finite-difference time-domain (FDTD) procedure is developed for the efficient analysis of the transient plane wave penetration inside a metallic-composite box. Suitable boundary conditions are enforced on the composite walls of the enclosure in order to link the MFIE and the FDTD solution schemes, which are applied respectively in the outer and inner volumes of the enclosure. Comparisons with a full FDTD approach are carried out to validate the procedure, The proposed hybrid MFIE/FDTD method is more efficient than the FDTD approach alone from the computational point of view, because it requires neither the discretization of the volume surrounding the enclosure, nor the use of absorbing boundary conditions to truncate the FDTD lattic
Efficient post-processing procedure for combined FDTD/TL transient analyses
No full textThis paper proposes an efficient post-processing procedure to be used in the combined three-dimensional (3-D) finite-difference time-domain transmission line (FDTD/TL) analysis of low-frequency transient problems involving complex wire structures. The method allows automatic computation, from the 3-D-FDTD solution, of the transient source terms representing the inputs of the TL analysi
Premio Sapienza Ricerca
No full textMateriali avanzati sono ampiamente utilizzati nell'industria aerospaziale per applicazioni sia strutturali che funzionali. Le nuove sfide poste dalla tecnologia di aeromobili interamente in materiale composito, quali il Boeing 787 e l'Airbus 380, e la complessità dei sistemi di navigazioni hanno portato verso lo sviluppo di nuovi materiali compositi micro/nano-strutturati progettati in modo da soddisfare contemporaneamente requisiti di tipo elettromagnetico, meccanico e funzionale. Sia in ambito civile che nei settori della sicurezza e della difesa, lo sviluppo di materiali ultraleggeri con proprietà radar assorbenti e di film sottili trasparenti schermanti ha avuto un notevole impulso al fine di sopprimere interferenze elettromagnetiche in sistemi critici.
Negli ultimi anni le nanotecnologie hanno rappresentato lo strumento necessario per lo sviluppo di nuovi materiali con proprietà controllate, per applicazioni avanzate nei settori dell'aerospazio e della sicurezza.
La ricerca è stata focalizzata sullo sviluppo di nuovi nanomateriali con proprietà elettromagnetiche e funzionali controllate, attraverso il progetto della struttura del materiale a partire dalla nano-scala. Sono state sviluppate due diverse tipologie di materiali: compositi multifase caricati con nanostrutture di carbonio e microinclusioni (quali polveri e nanofibre di carbonio metallizzate) e film sottili multistrato nanostrutturati.
La ricerca è stata finanziata da industrie operanti nel settore aerospaziale e della sicurezza, quali Alenia Aeronautica, Thales Alenia Space, Selex Sistemi Integrati, e nell'ambito di programmi di ricerca nazionali e internazionali
Past President Memoria Award
No full textPremio per migliore giovane ricercatore nel settore della Compatibilità Elettromagnetica nell'anno 199
A new model for the FDTD analysis of the shielding performances of thin composite structures
No full textA new model is proposed for the transient analysis of the electromagnetic field penetration through air-embedded conductive structures realized by thin multilayered composite panels. A magnetic field controlled formulation is developed in the frequency-domain to express the tangential components of the electric field on the external faces of the composite slab as a function of the tangential components of the magnetic field by means of the surface and transfer impedances of the thin panel coated on a perfect magnetic medium. The corresponding time-domain model is obtained by applying the inverse Fourier transform to the field quantities; an efficient piecewise linear convolution procedure is developed for the numerical calculation of the resulting convolution integrals. The model is implemented in one-dimensional (1-D) and two-dimensional (2-D) FDTD codes and applied to the analysis of different shielding configurations, both in the frequency and in the time domai
Electromagnetic interference from carrier channels on finite-length power lines above a lossy ground in a wide frequency-range
No full textPrediction models of the electromagnetic interference generated by carrier channels on multiconductor power distribution lines with nonradiating terminal loads are presented. The proposed formulations are addressed to the evaluation of the radiated field components in a wide frequency-range, by including the effects of the lossy ground plane and removing the hypothesis of unidirectional current propagation. The validity of the infinite-length approximation and of the complex image approach are investigated, with reference to different line-configuration, in case of wire-to-ground and wire-to-wire signal transmissio
- …
