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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 : Conception des filtres optiques a base de cristaux photoniques pour application dans les routeurs optiques dans les reseaux de telecomunications optiques Type de document : texte imprimé Auteurs : Abdelali Boudissa, Auteur ; Malek Benslama, Directeur de thèse Editeur : Constantine : Université Mentouri Constantine Année de publication : 2013 Importance : 87 f. Format : 30 cm. Note générale : 2 copies imprimées disponibles Langues : Français (fre) Catégories : Français - Anglais
ElectroniqueTags : Cristaux photoniques couplage cavité-guide d’onde cavité résonante filtre optique Filtre Passe Bande Channel Drop Filter la méthode FDTD la méthode PWE Photonic crystal coupled cavity waveguides resonant cavity optical filter Band Pass Filter FDTD method PWE method البلورات الصوئية الدليل الموجي تجويف رنان مرشح بضري ممر الموجة طريقةPW طريقةFDTD مرشح قناة قطرة Index. décimale : 621 Electronique Résumé : The implanting of optical routers in telecommunication optical network necessitates the modeling constituent’s amounts and approvals which encircle the considered router. For it, in this work, we investigate three types of filters with base 2D photonic crystals. The first, it is a narrow band optical filter, this system is constituted with two waves guides obtained by omitting one row of holes of the photonic crystal, coupled among them by a resonant cavity formed by a point of defect in the crystal. Near the resonant frequency (??a/2πc = 0.38), light from the input waveguide can couple into the cavity, and the cavity in turn can couple into the output waveguide, is that the peak transmission is precisely 100%.Then a Band Pass Filter is proposed, the out put transmission spectra of our filter covered three band. Band I covers the wavelength range from 1.331 to 1.355 μm has 86% of transmission power, Band II, from 1.390 to 1.427 μm, has 98% of the transmission power and Band III from 1.46 to 1.507 μm, and has 27% of the transmission power. The full width at half maximum bandwidth of these bands is 9.7, 13.1 and 16.4 nm,respectively. And finally a new constitution of “Channel Drop Filter " is simulated, it consists of two waveguides bends coupled among them by linear resonant cavity. The power dropped from the input waveguide bend into the drop channel at 1550 nm (the resonant frequency)is about 89%; the power transferred to the other channels is less than 5%. The Band of out put transmission spectra of the drop channel cover the wavelength range from 1505 to 1600 nm and the bandwidth is about 12.7 nm and the Q factor is 122.
The temporal and spectral behavior of the device is studied using two dimensional Finite Difference Time Domain Method (2D-FDTD) and Plane Wave Expansion (PWE) methods respectively.Diplôme : Doctorat en sciences En ligne : ../theses/electronique/BOU6325.pdf Format de la ressource électronique : Permalink : https://bu.umc.edu.dz/md/index.php?lvl=notice_display&id=6291 Conception des filtres optiques a base de cristaux photoniques pour application dans les routeurs optiques dans les reseaux de telecomunications optiques [texte imprimé] / Abdelali Boudissa, Auteur ; Malek Benslama, Directeur de thèse . - Constantine : Université Mentouri Constantine, 2013 . - 87 f. ; 30 cm.
2 copies imprimées disponibles
Langues : Français (fre)
Catégories : Français - Anglais
ElectroniqueTags : Cristaux photoniques couplage cavité-guide d’onde cavité résonante filtre optique Filtre Passe Bande Channel Drop Filter la méthode FDTD la méthode PWE Photonic crystal coupled cavity waveguides resonant cavity optical filter Band Pass Filter FDTD method PWE method البلورات الصوئية الدليل الموجي تجويف رنان مرشح بضري ممر الموجة طريقةPW طريقةFDTD مرشح قناة قطرة Index. décimale : 621 Electronique Résumé : The implanting of optical routers in telecommunication optical network necessitates the modeling constituent’s amounts and approvals which encircle the considered router. For it, in this work, we investigate three types of filters with base 2D photonic crystals. The first, it is a narrow band optical filter, this system is constituted with two waves guides obtained by omitting one row of holes of the photonic crystal, coupled among them by a resonant cavity formed by a point of defect in the crystal. Near the resonant frequency (??a/2πc = 0.38), light from the input waveguide can couple into the cavity, and the cavity in turn can couple into the output waveguide, is that the peak transmission is precisely 100%.Then a Band Pass Filter is proposed, the out put transmission spectra of our filter covered three band. Band I covers the wavelength range from 1.331 to 1.355 μm has 86% of transmission power, Band II, from 1.390 to 1.427 μm, has 98% of the transmission power and Band III from 1.46 to 1.507 μm, and has 27% of the transmission power. The full width at half maximum bandwidth of these bands is 9.7, 13.1 and 16.4 nm,respectively. And finally a new constitution of “Channel Drop Filter " is simulated, it consists of two waveguides bends coupled among them by linear resonant cavity. The power dropped from the input waveguide bend into the drop channel at 1550 nm (the resonant frequency)is about 89%; the power transferred to the other channels is less than 5%. The Band of out put transmission spectra of the drop channel cover the wavelength range from 1505 to 1600 nm and the bandwidth is about 12.7 nm and the Q factor is 122.
The temporal and spectral behavior of the device is studied using two dimensional Finite Difference Time Domain Method (2D-FDTD) and Plane Wave Expansion (PWE) methods respectively.Diplôme : Doctorat en sciences En ligne : ../theses/electronique/BOU6325.pdf Format de la ressource électronique : Permalink : https://bu.umc.edu.dz/md/index.php?lvl=notice_display&id=6291 Exemplaires (1)
Code-barres Cote Support Localisation Section Disponibilité BOU/6325 BOU/6325 Thèse Bibliothèque principale Thèses Disponible Documents numériques
texte intégraleAdobe Acrobat PDF
Titre : Caractérisation d’une antenne microbande couplée par une ouverture de forme rectangulaire. Application à la réalisation d’une antenne multibande. Type de document : texte imprimé Auteurs : Leila Chouti, Auteur ; Abdelmadjid Benghalia, Directeur de thèse Editeur : جامعة الإخوة منتوري قسنطينة Année de publication : 2018 Importance : 112 f. Format : 30 cm. Note générale : 2 copies imprimées disponibles
Langues : Français (fre) Catégories : Français - Anglais
ElectroniqueTags : Antenne microruban antenne microruban couplée par une ouverture méthode des différences finies (FDTD) système MIMO antenne multi bande microstrip antenna aperture microstrip antenna FDTD method MIMO system multiband antenna ھوائیات میكرو شریطیة ھوائیات المیكرو شریطیة المقترنة بفتحة طریقة FDTD
نظام MIMOھوائي متعدد النطاقاتIndex. décimale : 621 Electronique Résumé : The main purpose of this thesis was to study, modeling and design of printed antennas. Three main parts have formed the body of this thesis. In the first part, we have developed two methods for modeling a rectangular microstrip antenna with a rectangular aperture in the ground plane. The first method is based on the determination of hybrid dyadic Green’s functions in the spectral domain, while in the second method, we have applied the finite difference time domain for the analysis of the microstrip antenna. The two methods have been
validated by comparing our numerical results with experimental measurements as well as with results obtained using the HFSS simulation software.
The second part has been devoted to the study of performances of two multi-antennas systems. Each system has eight radiating elements having as a basic element a microstrip patch. The main difference between these two systems lies in the excitation technique, where the radiating elements of the second multi-antenna system have been fed through apertures cut into the ground plane. The performances in terms of adaptation and isolation for these two systems have been discussed. Results concerning the radiation patterns and gain have been also presented.
In the third part of this thesis, our efforts were directed towards the design of a new tri-band triangular monopole antenna structure. A rectangle-shaped aperture has been etched on the radiating element to generate the second resonant frequency. To obtain the third resonant frequency, a pair of symmetrical L-shaped parasitic elements has been added on both sides of the triangular monopole antenna. A coplanar waveguide feeding mechanism has been used to provide good performances on all bands. The CST simulation software has been used in the
optimization of the parameters of the proposed antenna. A prototype of the proposed antenna has been fabricated in the RF laboratory of the INRS in Montreal, Canada.
The simulated results in terms of reflection coefficient and radiation pattern have been compared with experimental measurements and a good agreement has been obtained.
Measured and simulated results demonstrate that the proposed antenna can achieve three desired operating bands, higher isolation characteristic between adjacent bands. A stable gain and a good omnidirectional radiation in the H-plane have also been achieved. As a result, the performances offered by the proposed antenna are very promising for practical WLAN/WiMAX applications.
Diplôme : Doctorat en sciences En ligne : ../theses/electronique/CHO7294.pdf Format de la ressource électronique : Permalink : https://bu.umc.edu.dz/md/index.php?lvl=notice_display&id=10909 Caractérisation d’une antenne microbande couplée par une ouverture de forme rectangulaire. Application à la réalisation d’une antenne multibande. [texte imprimé] / Leila Chouti, Auteur ; Abdelmadjid Benghalia, Directeur de thèse . - جامعة الإخوة منتوري قسنطينة, 2018 . - 112 f. ; 30 cm.
2 copies imprimées disponibles
Langues : Français (fre)
Catégories : Français - Anglais
ElectroniqueTags : Antenne microruban antenne microruban couplée par une ouverture méthode des différences finies (FDTD) système MIMO antenne multi bande microstrip antenna aperture microstrip antenna FDTD method MIMO system multiband antenna ھوائیات میكرو شریطیة ھوائیات المیكرو شریطیة المقترنة بفتحة طریقة FDTD
نظام MIMOھوائي متعدد النطاقاتIndex. décimale : 621 Electronique Résumé : The main purpose of this thesis was to study, modeling and design of printed antennas. Three main parts have formed the body of this thesis. In the first part, we have developed two methods for modeling a rectangular microstrip antenna with a rectangular aperture in the ground plane. The first method is based on the determination of hybrid dyadic Green’s functions in the spectral domain, while in the second method, we have applied the finite difference time domain for the analysis of the microstrip antenna. The two methods have been
validated by comparing our numerical results with experimental measurements as well as with results obtained using the HFSS simulation software.
The second part has been devoted to the study of performances of two multi-antennas systems. Each system has eight radiating elements having as a basic element a microstrip patch. The main difference between these two systems lies in the excitation technique, where the radiating elements of the second multi-antenna system have been fed through apertures cut into the ground plane. The performances in terms of adaptation and isolation for these two systems have been discussed. Results concerning the radiation patterns and gain have been also presented.
In the third part of this thesis, our efforts were directed towards the design of a new tri-band triangular monopole antenna structure. A rectangle-shaped aperture has been etched on the radiating element to generate the second resonant frequency. To obtain the third resonant frequency, a pair of symmetrical L-shaped parasitic elements has been added on both sides of the triangular monopole antenna. A coplanar waveguide feeding mechanism has been used to provide good performances on all bands. The CST simulation software has been used in the
optimization of the parameters of the proposed antenna. A prototype of the proposed antenna has been fabricated in the RF laboratory of the INRS in Montreal, Canada.
The simulated results in terms of reflection coefficient and radiation pattern have been compared with experimental measurements and a good agreement has been obtained.
Measured and simulated results demonstrate that the proposed antenna can achieve three desired operating bands, higher isolation characteristic between adjacent bands. A stable gain and a good omnidirectional radiation in the H-plane have also been achieved. As a result, the performances offered by the proposed antenna are very promising for practical WLAN/WiMAX applications.
Diplôme : Doctorat en sciences En ligne : ../theses/electronique/CHO7294.pdf Format de la ressource électronique : Permalink : https://bu.umc.edu.dz/md/index.php?lvl=notice_display&id=10909 Exemplaires (1)
Code-barres Cote Support Localisation Section Disponibilité CHO/7294 CHO/7294 Thèse Bibliothèque principale Thèses Disponible
Titre : Etude theorique des materiaux a bandes interdites photoniques bidimensionnels : applications dans le domaine du guidage optique et la detection Type de document : texte imprimé Auteurs : Feida Bougriou, Auteur ; Touraya Bouchemat -Boumaza, Directeur de thèse Editeur : constantine [Algérie] : Université Constantine 1 Année de publication : 2013 Importance : 158 f. Format : 30 cm. Note générale : 2 copies imprimées disponibles Langues : Français (fre) Catégories : Français - Anglais
ElectroniqueTags : cristaux photoniques guide d'ondes à CP guides virages Senseur à haute
sensibilité la méthode FDTD la méthode PWE Photonic crystal bend waveguide PC waveguide PC sensor High sensitivity FDTD method PWE method البلورات الفوتونیة موجه الموجة في البلورات الفوتونیة موجه الموجة المنحني اجهزة الاستشعار الحساسیة العالیة طریقة
FDTD طریقة
PWE FDTDIndex. décimale : 621 Electronique Résumé : Photonic crystals are nanostructured materials with submicron feature sizes allow unprecedented control of light confinement and enable the miniaturization of main optical functions. Precisely, this thesis is a body of work that builds on the design and development of new components based on photonic crystals for applications in light guiding and high sensitivity detection, using a method based on solving Maxwell's equations finite difference in the 2D-FDTD dimensional time domain.
The single line defect photonic crystal waveguide is one of the devices that have been widely explored. Most photonic crystal waveguide structures are designed and fabricated in triangular lattice with circular holes. We designed a single row W1 triangular lattice with a
judicious choice of parameters guide. We evaluated the transmission in the guide and we got a maximum transmission about of 60% on the entire band related to the PBG. Another type of guide has been designed, it is the bend guide W1 triangular lattice, by optimizing the topology of the bend, we have shown that the transmission bend circuit is much improved over a wide range.
PC waveguide is one class of PC devices that has been demonstrated for RI (refractive index) measurements. For the development of two dimensional reconfigurable photonic circuits, we propose an RI sensor based on single line PCW structure.
When the PC’s air holes are full of homogenous de-ionized water, the wavelength position of band edges of this sensor will shift accordingly due to the variation of RI. The sensor is sensitive to the change of RI in the air hole and it can be optimized to realize high sensitivity,wide measurement range and improved transmission. It has been observed that a 306 nm
wavelength position of the lower band edge shift was observed corresponding to a sensitivity of more than 927 nm/RIU (refractive index nit).Diplôme : Doctorat en sciences En ligne : ../theses/electronique/BOU6431.pdf Format de la ressource électronique : Permalink : https://bu.umc.edu.dz/md/index.php?lvl=notice_display&id=9455 Etude theorique des materiaux a bandes interdites photoniques bidimensionnels : applications dans le domaine du guidage optique et la detection [texte imprimé] / Feida Bougriou, Auteur ; Touraya Bouchemat -Boumaza, Directeur de thèse . - constantine [Algérie] : Université Constantine 1, 2013 . - 158 f. ; 30 cm.
2 copies imprimées disponibles
Langues : Français (fre)
Catégories : Français - Anglais
ElectroniqueTags : cristaux photoniques guide d'ondes à CP guides virages Senseur à haute
sensibilité la méthode FDTD la méthode PWE Photonic crystal bend waveguide PC waveguide PC sensor High sensitivity FDTD method PWE method البلورات الفوتونیة موجه الموجة في البلورات الفوتونیة موجه الموجة المنحني اجهزة الاستشعار الحساسیة العالیة طریقة
FDTD طریقة
PWE FDTDIndex. décimale : 621 Electronique Résumé : Photonic crystals are nanostructured materials with submicron feature sizes allow unprecedented control of light confinement and enable the miniaturization of main optical functions. Precisely, this thesis is a body of work that builds on the design and development of new components based on photonic crystals for applications in light guiding and high sensitivity detection, using a method based on solving Maxwell's equations finite difference in the 2D-FDTD dimensional time domain.
The single line defect photonic crystal waveguide is one of the devices that have been widely explored. Most photonic crystal waveguide structures are designed and fabricated in triangular lattice with circular holes. We designed a single row W1 triangular lattice with a
judicious choice of parameters guide. We evaluated the transmission in the guide and we got a maximum transmission about of 60% on the entire band related to the PBG. Another type of guide has been designed, it is the bend guide W1 triangular lattice, by optimizing the topology of the bend, we have shown that the transmission bend circuit is much improved over a wide range.
PC waveguide is one class of PC devices that has been demonstrated for RI (refractive index) measurements. For the development of two dimensional reconfigurable photonic circuits, we propose an RI sensor based on single line PCW structure.
When the PC’s air holes are full of homogenous de-ionized water, the wavelength position of band edges of this sensor will shift accordingly due to the variation of RI. The sensor is sensitive to the change of RI in the air hole and it can be optimized to realize high sensitivity,wide measurement range and improved transmission. It has been observed that a 306 nm
wavelength position of the lower band edge shift was observed corresponding to a sensitivity of more than 927 nm/RIU (refractive index nit).Diplôme : Doctorat en sciences En ligne : ../theses/electronique/BOU6431.pdf Format de la ressource électronique : Permalink : https://bu.umc.edu.dz/md/index.php?lvl=notice_display&id=9455 Exemplaires (1)
Code-barres Cote Support Localisation Section Disponibilité BOU/6431 BOU/6431 Thèse Bibliothèque principale Thèses Disponible Documents numériques
BOU6431_1.pdfAdobe Acrobat PDF
texte intégraleAdobe Acrobat PDF
