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Partager le résultat de cette recherche Interroger des sources externesContribution au développement d’une méthode temporelle pour la modélisation des structures hyperfréquences. / Rostom Khalef
Titre : Contribution au développement d’une méthode temporelle pour la modélisation des structures hyperfréquences. Type de document : texte imprimé Auteurs : Rostom Khalef, Auteur ; Mohamed-Taoufik Benhabiles, Directeur de thèse Mention d'édition : 24/11/2019 Editeur : جامعة الإخوة منتوري قسنطينة Année de publication : 2019 Importance : 137 f. Format : 30 cm. Note générale : 1 copies imprimées disponibles
Langues : Français (fre) Catégories : Français - Anglais
ElectroniqueTags : Electronique: Télécommunications méthodes sans maillage méthode CN-RPIM condition CFL méthode FDTD inconditionnellement stable méthode RPIM la méthode RBF modélisation meshless methods CN-RPIM method CFL condition FDTD method unconditionally stable RPIM method RBF method modeling طرق شبكية طريقةCN-RPIM شرط الاستقرارCFL طريقة FDTD ثبات غير مشروط طريقة RPIMِ طريقة RBF النمذجة Index. décimale : 621 Electronique Résumé :
Numerical simulation has become a central tool in the modeling of many microwave structures that sometimes suffer from discontinuities, which are difficult to model by conventional techniques, as required by powerful design and modeling methods. In addition, because of the increase in frequencies, it has become necessary to predict temporal responses to instantly evaluate the performance of these structures over broad frequency bands.
Due to the restrictions imposed on traditional numerical methods due to its dependence on meshes, meshless methods have become an indispensable scientific tool in electromagnetic modeling because they have freed the difficulties of the classical methods discretization grid. The approximation of the Maxwell equations on the one hand and they are based essentially on the basic functions according to their mathematical formulations on the other hand, which distinguishes them from low computation costs compared with other conventional techniques. However, to obtain convergence and obtain accurate results, the meshless methods suffer from a Courant-Friedrichs-Lewy (CFL) stability problem that limits the time step must be satisfied in practical simulations. Consequently, the computation time can be prohibitive for the fine electromagnetic modeling which requires their integration with the unconditionally stable implicit schemes. In this context, on the one hand, many algorithms have been proposed to solve the
Maxwell differential equations in the time domain for the simulation of some microwave structures which are: the meshless method based on the basis radial functions (RBF) and meshless radial point interpolation (RPIM) method. On the other hand, presentation of a new unconditionally stable two-dimensional radial point interpolation (RPIM) meshless method based on the Crank-Nicolson (CN) scheme. The implicit scheme of CN in the proposed algorithm is
applied to only one of Maxwell's equations. This leads to solving the time-domain second-order vector wave equation. Therefore a single electromagnetic field is explicitly updated at each iteration. The CFL requirement in the proposed CN-RPIM wave equation method does not limit the time step due to its implicit formulation. To value the proposed CN-RPIM method, numerical examples are used to validate and demonstrate efficiency and accuracy.
The numerical results are compared with those obtained by the explicit RPIM method and the FDTD method.
Note de contenu : Liste des Publications.
Diplôme : Doctorat en sciences En ligne : ../theses/electronique/KHA7592.pdf Format de la ressource électronique : Permalink : https://bu.umc.edu.dz/md/index.php?lvl=notice_display&id=11428 Contribution au développement d’une méthode temporelle pour la modélisation des structures hyperfréquences. [texte imprimé] / Rostom Khalef, Auteur ; Mohamed-Taoufik Benhabiles, Directeur de thèse . - 24/11/2019 . - جامعة الإخوة منتوري قسنطينة, 2019 . - 137 f. ; 30 cm.
1 copies imprimées disponibles
Langues : Français (fre)
Catégories : Français - Anglais
ElectroniqueTags : Electronique: Télécommunications méthodes sans maillage méthode CN-RPIM condition CFL méthode FDTD inconditionnellement stable méthode RPIM la méthode RBF modélisation meshless methods CN-RPIM method CFL condition FDTD method unconditionally stable RPIM method RBF method modeling طرق شبكية طريقةCN-RPIM شرط الاستقرارCFL طريقة FDTD ثبات غير مشروط طريقة RPIMِ طريقة RBF النمذجة Index. décimale : 621 Electronique Résumé :
Numerical simulation has become a central tool in the modeling of many microwave structures that sometimes suffer from discontinuities, which are difficult to model by conventional techniques, as required by powerful design and modeling methods. In addition, because of the increase in frequencies, it has become necessary to predict temporal responses to instantly evaluate the performance of these structures over broad frequency bands.
Due to the restrictions imposed on traditional numerical methods due to its dependence on meshes, meshless methods have become an indispensable scientific tool in electromagnetic modeling because they have freed the difficulties of the classical methods discretization grid. The approximation of the Maxwell equations on the one hand and they are based essentially on the basic functions according to their mathematical formulations on the other hand, which distinguishes them from low computation costs compared with other conventional techniques. However, to obtain convergence and obtain accurate results, the meshless methods suffer from a Courant-Friedrichs-Lewy (CFL) stability problem that limits the time step must be satisfied in practical simulations. Consequently, the computation time can be prohibitive for the fine electromagnetic modeling which requires their integration with the unconditionally stable implicit schemes. In this context, on the one hand, many algorithms have been proposed to solve the
Maxwell differential equations in the time domain for the simulation of some microwave structures which are: the meshless method based on the basis radial functions (RBF) and meshless radial point interpolation (RPIM) method. On the other hand, presentation of a new unconditionally stable two-dimensional radial point interpolation (RPIM) meshless method based on the Crank-Nicolson (CN) scheme. The implicit scheme of CN in the proposed algorithm is
applied to only one of Maxwell's equations. This leads to solving the time-domain second-order vector wave equation. Therefore a single electromagnetic field is explicitly updated at each iteration. The CFL requirement in the proposed CN-RPIM wave equation method does not limit the time step due to its implicit formulation. To value the proposed CN-RPIM method, numerical examples are used to validate and demonstrate efficiency and accuracy.
The numerical results are compared with those obtained by the explicit RPIM method and the FDTD method.
Note de contenu : Liste des Publications.
Diplôme : Doctorat en sciences En ligne : ../theses/electronique/KHA7592.pdf Format de la ressource électronique : Permalink : https://bu.umc.edu.dz/md/index.php?lvl=notice_display&id=11428 Exemplaires (1)
Code-barres Cote Support Localisation Section Disponibilité KHA75992 KHA75992 Thèse Bibliothèque principale Thèses Disponible
Titre : Contribution à l’élaboration d’un modèle electromagnétique de supports de transmission non-uniformes Type de document : texte imprimé Auteurs : Larbi Benkhaoua, Auteur ; Mohamed-Taoufik Benhabiles, Directeur de thèse Editeur : جامعة الإخوة منتوري قسنطينة Année de publication : 2016 Importance : 96 f. Format : 30 cm. Note générale : 2 copies imprimées disponibles
Langues : Français (fre) Catégories : Français - Anglais
ElectroniqueTags : équations des télégraphistes lignes de transmissions non-uniformes méthodes d’interpolation de point méthodes sans maillage modélisation Telegrapher’s Equations Nonuniform Transmission Lines Point
Interpolation Methods Meshless Methods modeling معادلات خطوط النقل خطوط النقل الكهربائية الغير موحدة طرق الحساب بدون شبكة النمذجةIndex. décimale : 621 Electronique Résumé : With the development of telecommunications and the need for miniaturizing microwave circuits and components, the uniform transmission lines were replaced by non uniform transmission lines (LTNUs) in many applications. With the presence of discontinuities uneasy to model by traditional methods, these lines require powerful technique of design and modeling, especially for arbitrary shapes. In addition, due to the increase in the operation frequencies, it became necessary to predict the transient responses to directly estimate the performances of the microwave circuits over ultra wide frequency bands.
On the other hand, the Meshless methods form a generic group of scientific computing
schemes which was developed since the years 1970s to eliminate the drawbacks of a fixed discretization grid for the approximation of the problem equations.
These methods have the advantages of arbitrary nodal distribution and conformal modeling of R.L.C.G parameters of NUTLs which require less computing costs than the traditional numerical methods.
In this context we implemented the MATLAB codes for the analysis and the simulation
of arbitrary non-uniform transmission lines in the time domain by three Meshless methods :
the polynomial point interpolation method (PIM), the meshless method based on radial
basis functions (RBF-MLM), and the radial point interpolation method (RPIM).
To illustrate the superiority of these methods, such as the irregular discretiszation and the fast convergence rate, results comparisons for two distinct samples were held between the PIM, the RBF-MLM, the RPIM, the FDTD method, and the wavelet expansion method.
These tests allow us to conclude that the RPIM converges quickly and provides the best
compromise between the accuracy and the computing time.Diplôme : Doctorat En ligne : ../theses/electronique/BEN6874.pdf Format de la ressource électronique : Permalink : https://bu.umc.edu.dz/md/index.php?lvl=notice_display&id=10190 Contribution à l’élaboration d’un modèle electromagnétique de supports de transmission non-uniformes [texte imprimé] / Larbi Benkhaoua, Auteur ; Mohamed-Taoufik Benhabiles, Directeur de thèse . - جامعة الإخوة منتوري قسنطينة, 2016 . - 96 f. ; 30 cm.
2 copies imprimées disponibles
Langues : Français (fre)
Catégories : Français - Anglais
ElectroniqueTags : équations des télégraphistes lignes de transmissions non-uniformes méthodes d’interpolation de point méthodes sans maillage modélisation Telegrapher’s Equations Nonuniform Transmission Lines Point
Interpolation Methods Meshless Methods modeling معادلات خطوط النقل خطوط النقل الكهربائية الغير موحدة طرق الحساب بدون شبكة النمذجةIndex. décimale : 621 Electronique Résumé : With the development of telecommunications and the need for miniaturizing microwave circuits and components, the uniform transmission lines were replaced by non uniform transmission lines (LTNUs) in many applications. With the presence of discontinuities uneasy to model by traditional methods, these lines require powerful technique of design and modeling, especially for arbitrary shapes. In addition, due to the increase in the operation frequencies, it became necessary to predict the transient responses to directly estimate the performances of the microwave circuits over ultra wide frequency bands.
On the other hand, the Meshless methods form a generic group of scientific computing
schemes which was developed since the years 1970s to eliminate the drawbacks of a fixed discretization grid for the approximation of the problem equations.
These methods have the advantages of arbitrary nodal distribution and conformal modeling of R.L.C.G parameters of NUTLs which require less computing costs than the traditional numerical methods.
In this context we implemented the MATLAB codes for the analysis and the simulation
of arbitrary non-uniform transmission lines in the time domain by three Meshless methods :
the polynomial point interpolation method (PIM), the meshless method based on radial
basis functions (RBF-MLM), and the radial point interpolation method (RPIM).
To illustrate the superiority of these methods, such as the irregular discretiszation and the fast convergence rate, results comparisons for two distinct samples were held between the PIM, the RBF-MLM, the RPIM, the FDTD method, and the wavelet expansion method.
These tests allow us to conclude that the RPIM converges quickly and provides the best
compromise between the accuracy and the computing time.Diplôme : Doctorat En ligne : ../theses/electronique/BEN6874.pdf Format de la ressource électronique : Permalink : https://bu.umc.edu.dz/md/index.php?lvl=notice_display&id=10190 Exemplaires (1)
Code-barres Cote Support Localisation Section Disponibilité BEN/6874 BEN/6874 Thèse Bibliothèque principale Thèses Disponible
