Diffraction by dielectric wedges: high frequency and time domain solutions

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Soggetto
Diffrazione; OtticaAbstract
The knowledge of the propagation characteristics of the electromagnetic fields is fundamental in the analysis and planning of modern radio communication systems. When the dimensions of the systems are large in terms of the electromagnetic wavelength, diffraction contributions due to material discontinuities can’t be negligible and must be accurately calculated.
In this work are presented the explicit closed form solutions for the highfrequency evaluation of the electromagnetic field produced inside and outside an arbitraryangled lossless penetrable wedge. Primarily, the full problem of the diffraction of plane waves by an acuteangled dielectric wedge is analyzed and solved. Then, its solutions are generalized to the cases of right and obtuseangled wedges. Both cases of E and Hpolarized incident plane waves are addressed in the study. The problems is tackled and solved in the framework of the uniform theory of diffraction, so that the total field at the observation point is determined by adding the geometrical optics contributions and the diffraction one. This last is obtained by performing a uniform asymptotic evaluation of the radiation integrals arising from a physical optics approximation for the equivalent electric and magnetic surface currents lying on the wedge boundaries. The solutions for the diffracted field are able to compensate the discontinuities of the geometrical optics field at the shadow boundaries and their accuracy is assessed by comparisons with data produced by numerical tools.
The big advantage of this approach consists in the possibility of evaluating the corresponding diffraction coefficients in the time domain for the same geometries. The inverse Laplace transform is applied to the frequency domain solutions for the diffraction coefficients and the transient diffracted field is evaluated via a convolution integral. Simulations have verified the goodness of the time domain solutions, too. To the author’s knowledge, no other closed form solutions for time domain scattering problems involving penetrable wedges are available in literature. [edited by Author]
Descrizione
2013  2014
Collections
Data
20160518Autore
Frongillo, Marcello
Metadata
Mostra tutti i dati dell'itemAutori  Frongillo, Marcello  
Data Realizzazione  20170302T10:46:05Z  
Date Disponibilità  20170302T10:46:05Z  
Data di Pubblicazione  20160518  
Identificatore (URI)  http://hdl.handle.net/10556/2337  
Identificatore (URI)  http://dx.doi.org/10.14273/unisa752  
Descrizione  2013  2014  it_IT 
Abstract  The knowledge of the propagation characteristics of the electromagnetic fields is fundamental in the analysis and planning of modern radio communication systems. When the dimensions of the systems are large in terms of the electromagnetic wavelength, diffraction contributions due to material discontinuities can’t be negligible and must be accurately calculated. In this work are presented the explicit closed form solutions for the highfrequency evaluation of the electromagnetic field produced inside and outside an arbitraryangled lossless penetrable wedge. Primarily, the full problem of the diffraction of plane waves by an acuteangled dielectric wedge is analyzed and solved. Then, its solutions are generalized to the cases of right and obtuseangled wedges. Both cases of E and Hpolarized incident plane waves are addressed in the study. The problems is tackled and solved in the framework of the uniform theory of diffraction, so that the total field at the observation point is determined by adding the geometrical optics contributions and the diffraction one. This last is obtained by performing a uniform asymptotic evaluation of the radiation integrals arising from a physical optics approximation for the equivalent electric and magnetic surface currents lying on the wedge boundaries. The solutions for the diffracted field are able to compensate the discontinuities of the geometrical optics field at the shadow boundaries and their accuracy is assessed by comparisons with data produced by numerical tools. The big advantage of this approach consists in the possibility of evaluating the corresponding diffraction coefficients in the time domain for the same geometries. The inverse Laplace transform is applied to the frequency domain solutions for the diffraction coefficients and the transient diffracted field is evaluated via a convolution integral. Simulations have verified the goodness of the time domain solutions, too. To the author’s knowledge, no other closed form solutions for time domain scattering problems involving penetrable wedges are available in literature. [edited by Author]  it_IT 
Lingua  en  it_IT 
Editore  Universita degli studi di Salerno  it_IT 
Soggetto  Diffrazione  it_IT 
Soggetto  Ottica  it_IT 
Titolo  Diffraction by dielectric wedges: high frequency and time domain solutions  it_IT 
Tipo  Doctoral Thesis  it_IT 
MIUR  INGINF/02 CAMPI ELETTROMAGNETICI  it_IT 
Coordinatore  Longo, Maurizio  it_IT 
Ciclo  XIII n.s.  it_IT 
Tutor  Riccio, Giovanni  it_IT 
Dipartimento  Ingegneria dell’Informazione ed Elettrica e Matematica Applicata  it_IT 