Oscar A. Peverini

Learn More
This paper presents an efficient implementation of spectral-element methods (SEMs) for the analysis of 2-D wave guide components with sharp edges. The well-known problem of ill conditioning of the mass matrix when very high-order polynomial basis functions are augmented with singular functions is addressed. A numerical process for the definition of a set of(More)
In this work a mortar-element method aimed at analyzing 2D periodic structures is introduced. The mathematical formulation of a single-domain problem involving periodicity conditions is derived; then, the multi-domain feature of this numerical scheme is exploited, in order to separate regions with media with different refraction indices. Finally, a(More)
This paper presents a Q-band orthomode transducer (OMT) that has been designed according to the mechanical constraints of the platelet (multi-layer) manufacturing strategy. It is composed of a twofold symmetric coupling section with two electrically identical recombination networks. The two OMT outputs lay on the same plane to provide a suitable interface(More)
A full-wave simulator of 2-D dielectric periodic structures under skew plane wave incidence is presented in this paper. A differential formulation is used and the boundary value problem is solved by means of a multi-domain spectral method. Suitable mappings allow the efficient analysis of dielectric elements with rounded corner cross sections. A comparison(More)
Surface acoustic wave (SAW) interdigital transducers are key components in X-Y LiNbO3 acousto-optical (A-O) devices. SAW interdigital transducers (IDT's) on this substrate exhibit a high spurious resonance that may reduce the A-O efficiency. In this paper we present a detailed analysis of X-Y LiNbO3 IDT's based on a fast Green's function method (GFM). In(More)
SPOrt (Sky Polarization Observatory) is a space experiment to be flown on the International Space Station during Early Utilization Phase aimed at measuring the microwave polarized emission with FWHM=7 • , in the frequency range 22-90 GHz. The Galactic polarized emission can be observed at the lower frequencies and the polarization of Cosmic Microwave(More)
Electromagnetic wave propagation in anisotropic inhomogeneous media is computed by a novel reduced-order model technique, which is based on the restriction of the Marcuvitz-Schwinger equations on Krylov subspaces and on the application of the singular-value decomposition. The model is derived from the standard coupled-wave method and includes both(More)
We report on a detailed theoretical and experimental investigation of film-loaded surface acoustic wave (SAW) waveguides in lithium niobate (LiNbO3) for integrated acousto-optical (AO) polarization converters. The numerical analysis is based on both a scalar and a full-vectorial model. Dispersion plots and figures of merit for several structures are given,(More)