Dissertations / Theses on the topic 'Dispositifs électromagnétiques – Conception et construction'
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Delma, Ouendpouire Jude. "Étude des matériaux magnétiques composites à particules lamellaires - application à la conception des machines à flux transverse Clawpole à Stator Hybride." Thesis, Université Laval, 2009. http://www.theses.ulaval.ca/2009/26424/26424.pdf.
Full textTan, Wenhua. "Modélisation et Conception des Composants Passifs Planar pour Filtres CEM." Phd thesis, Ecole Centrale de Lille, 2012. http://tel.archives-ouvertes.fr/tel-00776515.
Full textNgoua, teu Magambo Jean-Sylvio. "Modélisaton et conception de transformateurs planar pour convertisseur de puissance DC/DC embarqué." Thesis, Ecole centrale de Lille, 2017. http://www.theses.fr/2017ECLI0025.
Full textThese thesis works deal with the issue of the planar transformers development for power integration, in the context of the More Electric Aircraft (MEA), where the constraints of volume and weight are paramount. Magnetic components remain a hindrance to the integration of Power Electronics systems and planar components (transformers and inductors) offer an interesting alternative to wound components for reducing the size of converters.In these works, methods, a sizing tool and prototypes of planar transformers (2 and 3 windings) in strip and PCB technology are developed for aeronautical DC / DC converter applications. Firstly, the models allowing the calculation of the losses, the estimation of the temperature rise and the calculation of the leakage inductance are presented and compared in order to design calculation tools for engineers. In a second step, it is shown that the modification of the shape of the angles of rectangular turns makes it possible to significantly reduce the HF copper losses.Based on these tools and results, prototypes of 3-windings planar transformers in multilayer PCBs are developed. Many prototypes are characterized and validate the proposed designing models. Finally, one of these prototypes is integrated and tested in a DC / DC power converter of 3.75kW highlighting the gains obtained
Deng, Siyang. "Méthodes de conception par optimisation robuste et fiable de dispositifs électromagnétiques." Thesis, Ecole centrale de Lille, 2018. http://www.theses.fr/2018ECLI0001/document.
Full textThis PhD thesis deals with the robust and reliability-based optimization problems under input uncertainty.First, the different categories of stochastic optimization methods to treat the uncertainty are presented. These methods aim to find a more robust and/or reliable solution by minimize the variance of objective and reducing the probability to violate the constraints in different ways. Each categories has various approaches and after comparison, the most effective ones are selected.However, as these methods increase the number of evaluation than deterministic optimization and need the gradient information which may be noisy provided by time-consuming models like finite element models, they are not suitable for the heavy models. So kriging-based meta-model strategies are proposed in this manuscript as it could use the determination of small size sample to approach complex functions and give accurate derivatives. The original objective function and constraints are progressively replaced by kriging meta-models using infill sampling criterion to add samples in the process of optimization. Different strategies including the choice of the criterion and the positioning of sample enrichment for each categories are compared and highlight the most effective ones.Then the optimization approaches developed within this research work are applied to the analytic and finite element models of a transformer for solving an electromagnetic optimization problems
Saboureau, Cédrick. "Analyses électromagnétiques et méthodologies de conception associées, dédiées à l'optimisation de composants et modules millimétriques." Limoges, 2004. http://aurore.unilim.fr/theses/nxfile/default/119d4f2c-4055-477f-b8e3-b30e2e9035d5/blobholder:0/2004LIMO0050.pdf.
Full textThis work contributes to the development of electromagnetic methods dedicated to the conception of transceiver modules. These investigations demonstrate the potential of electromagnetic tools. For each system analysis, we present the method of conception, taking into account physical and technological parameters, complying with industries requirements. The first part is dedicated to developing a specific procedure for the optimisation of Ka band interdigital filters, considering non-adjacent couplings. The second part investigates a new topology for a microstrip-to-waveguide transition, using a patch with "U" slot. Finally the last two parts present the conception of broadband interconnections used for MMICs mounting on substrate boards. The whole work has been realized in close collaboration with important telecommunication companies
Choubani, Fethi. "Étude et conception des oscillateurs : application aux capteurs électromagnétiques." Toulouse, INPT, 1993. http://www.theses.fr/1993INPT045H.
Full textRios, José. "Etude et conception de dispositifs MOS-Thyristor autoamorçables et à blocage commandé." Toulouse 3, 1996. http://www.theses.fr/1996TOU30014.
Full textBencheikh, Nabil. "Conception et réalisation d'un convoyeur électromagnétique planaire miniature." Compiègne, 2006. http://www.theses.fr/2006COMP1661.
Full textThe work presented in this thesis report is dedicated to design of a miniature electromagnetic planar conveyor with three degrees of freedom using Laplace force. The mobile part of the conveyor consists in four linear actuators stuck in cross structure. Each linear is composed of permanent magnets layout as the mobile part and planar electric drive coils as the fixed part. The permanent magnets layout optimizes the magnetic induction near planar electric drive coils and increases the performances of linear actuator. The modelling of the linear actuator takes into account the electric, the magnetic and mechanical aspect. Simulation results are used to dimension the prototypes and to test the control law in closed loop configuration. Experimental tests validate the established model and give dynamical performances of each realised prototype. The results show the ability of actuator to move with 20 /-lm of displacement resolution and 5 nm of positioning resolution. Velocity 10 mm/s can be reached. The angular range of the final prototype is -8°/+8°
Botelho, Diego Pereira. "Méthode des éléments naturels appliquée aux problèmes électromagnétiques : développement d’un outil de modélisation et de conception des dispositifs électriques." Thesis, Université Grenoble Alpes (ComUE), 2015. http://www.theses.fr/2015GREAT138/document.
Full textIn order to overcome the limitations related to the finite element method’s (FEM) narrow dependency of the solution on the mesh, meshless or meshfree methods were developed over the last 20 years. These techniques present the advantage of yielding very smooth approximations, being able to respond more adequately to the increasing demands of applications. However, some intrinsic features of most of these approaches make the implementation difficult, often requiring additional specific techniques for the imposition of the boundary conditions and the treatment of physical discontinuities. Recently, the natural element method (NEM) was developed. This approach, based on the Voronoi diagram and the “natural neighbors” concepts, combines the advantages of very smooth approximations and a FEM-like implementation. This thesis focuses on the study and development of the NEM, dedicated to electrical engineering applications. The main purpose of this exploratory work is the study of the limitations, benefits and the potential of the NEM and its underlying concepts. Several analyses of NEM’s performance are presented. As far as the numerical integration, higher order approximations and the vector interpolation are concerned, original developments are proposed
Laval, Laurence. "Conception et caractérisation dosimétrique de dispositifs microondes pour des applications bioélectromagnétiques, liées à l'utilisation des téléphones portables." Limoges, 1999. http://www.theses.fr/1999LIMO0009.
Full textTrombert, Jean-Hugues. "Etude et caractérisation d'un système optoélectronique de génération d'impulsions électromagnétiques ultra-brèves : Application à la conception de bancs de mesure en millimétrique." Limoges, 1997. http://www.theses.fr/1997LIMO0038.
Full textLandari, Hamza. "Analyse et conception d'une micropompe pour des applications à très faible pression." Master's thesis, Université Laval, 2018. http://hdl.handle.net/20.500.11794/28319.
Full textIn this project, a new architecture of an air-driven micropump prototype with self-actuating microvalves is presented. A finite element model is also presented. Fabrication and characterization of the system and the electronic control of the micro-pump was also introduced. The designed micropump was able to generate a flow rate of 9 µL/min. Pumping pressure was 1500 Pa. Frequency of membrane deformation was 1.25 Hz and its maximum deformation was 3.66 µm. Finite element modeling shows that the flow rate ratio between the admission and delivery phase was 99.99 %. Fabrication of the micropump was achieved through two processes. First, a manual molding for microvalves with cylindrical and cubic chambers whose external dimensions was 8 mm x 12 mm x 6 mm and actuation membrane thickness of 20 µm. The entire system, including the membrane, was made from polydimethylsiloxane (PDMS). Second, in collaboration with the department of mechanical engineering, a new printing process based on sugar glass was also used. The latter is based on the 3D printing of a sugar mold. The mold is dissolved after the pouring and curing of PDMS. The actuating chambers of the micropump wetre cylindrical with a diameter of 4 mm and a height of 1 mm. The pumping chamber was also cylindrical with the same diameter but with a height of 0.5 mm. The thickness of the pumping membranes was 250 µm. Through this process, the entire pumping system (expect microvalves) were fabricated as a one block to eliminate leakage and reduce system dimensions. The external dimensions of the micropump was 20 mm x 20 mm x 10 mm. Experimental results of the micro-pump showed that the flow rate that can be generated is 7 µL/min. The electrical power consumption of the system was 114 mW. Finally, the microvalve can resist to a back pressure up to 13 psi. A graphical interface to control the actuation part of the micropump using an FPGA has also been developed.
Cloutier, Audrey. "Conception par voie magnétique de couches d'alignement pour dispositifs d'affichage à cristaux liquides." Thesis, Université Laval, 2011. http://www.theses.ulaval.ca/2011/26981/26981.pdf.
Full textColomes, Jérémie. "De la concertation à la co-construction, analyse des dispositifs de conception des politiques régionales d’économie sociale et solidaire." Thesis, Poitiers, 2019. http://www.theses.fr/2019POIT4002.
Full textThe cumulation of the SSE (2014) and NOTRe (2015) laws has significantly affected the production mechanism of public policies in the social solidarity economy (SSE). By creating a potentially co-constructed biennial EBS regional conference, the legislator has set up a space for expression around the design of public policies in the sector. By constraining the inclusion of the conclusions of this event in the design of the "ESS" part of the regional scheme of development of the economy, innovation and internationalization (SRDE2I), he reveals an interesting articulation between the two texts.The stakes of a co-construction – as such as a common, plural construction - of public policies are numerous. For the legislator, the goal is to answer to a lake of involvement from the citizens regarding politics. The problematic chosen by our statement is based on this approach, by investigating whether co-construction can involve the citizen better in the management of public affairs. Have local governments responded to the legislator's encouragement by co-constructing their conference? Has the SSE sector got mobilized? What does the legislator mean by co-construction? What was the interpretation of the Regions? For what result?Keywords: participative democracy; social and solidarity economy; democratic innovation; social innovation; regional policies
Avila, Sergio. "Optimisation multiobjectif et analyse de sensibilité appliquées à la conception de dispositifs. Application : Synthèse d'antennes à réflecteur embarquées dans un satellite." Phd thesis, Ecole Centrale de Lyon, 2006. http://tel.archives-ouvertes.fr/tel-00012065.
Full textThuriet, Jean. "Étude et conception de systèmes de validation de tâches d'assemblage : participation à la conception d'un robot collaboratif destiné à une chaîne de montage automobile." Master's thesis, Université Laval, 2019. http://hdl.handle.net/20.500.11794/34747.
Full textHospital, Fabien. "Conception préliminaire des actionneurs électromagnétiques basée sur les modèles : lois d'estimations et règles de conception pour la transmission de puissance mécanique." Thesis, Toulouse, INSA, 2012. http://www.theses.fr/2012ISAT0036/document.
Full textIn the continuity of work of research on embedded systems of mechanical transmission, this these has two objectives: to improve estimation models of Electromechanical Actuator (EMA) pieces and to extend the cross-cutting vision of preliminary design to the dynamic aspects. Indeed, in the preliminary design based on models, this research should allow to adapt the choice of architectures and technologies to static and dynamic performance to achieve. The models developed from the scaling laws will be extended and exploited to modelize elementary pieces of the EMA and to highlight rules of "good practices" in preliminary design. We focus in particular on the design of EMA in aeronautic field. In the first time, we developed estimations models and métamodèles of elementary components of EMA which was decomposed in housing and elementary pieces.In a second time, we established rules of good practices for actuator sizing in control position loop. Contrary to older researches, we take into account control synthesis to create these rules. From simulations models, we quantified the influence of technological defects of components (inertia and saturations, elasticity (backlash), friction) on EMA performances. Indeed, the usual command structures and the choice of the elements of control are intimately linked to the dynamic performance and these defects.Finally, to give test way to identify with accuracy a friction model in aeronautical conditions of temperature, a test bench of Harmonic Drive was create, integrated and implemented. It allows booting the validation of rules of good practices in preliminary design
St-Amand, Olivier. "Modélisation semi-analytique dynamique d'un actionneur THUNDER utilisé en isolation vibratoire." Thesis, Université Laval, 2012. http://www.theses.ulaval.ca/2012/28744/28744.pdf.
Full textKetfi-Cherif, Ahmed. "Modélisation mathématique d'organes de véhicules automobiles à basse consommation : applications en simulation, estimation et commande." Paris 9, 1999. https://portail.bu.dauphine.fr/fileviewer/index.php?doc=1999PA090037.
Full textCavalli, Christian. "Contribution à l'étude de multipoles planaires." Toulouse, INPT, 1991. http://www.theses.fr/1991INPT069H.
Full textCharpentier, Jean-Frédéric. "Modélisation des ensembles convertisseurs statiques-machines électriques par couplage des équations du champ électromagnétique et du circuit électrique." Toulouse, INPT, 1996. http://www.theses.fr/1996INPT065H.
Full textMuller, Philippe. "Conception, fabrication et caractérisation d'un microcommutateur radio fréquences pour des applications de puissance." Lille 1, 2005. https://pepite-depot.univ-lille.fr/LIBRE/Th_Num/2005/50376-2005-Muller.pdf.
Full textToussaint, Geneviève. "Modélisation du confinement des débris des pales d'un moteur d'avion dans un caisson hybride métal-composite." Master's thesis, Université Laval, 2007. http://hdl.handle.net/20.500.11794/19372.
Full textLuan, Quoc Hung. "Etude et mise en oeuvre de techniques d'assemblages hybrides pour l'intégration tridimensionnelle en électronique de puissance." Toulouse 3, 2010. http://thesesups.ups-tlse.fr/873/.
Full textIn Power Electronics Applications, the general trend is to develop integration leading to an increase of the power density and a decrease of volume, weight and cost while maintaining a high level of reliability. It is particularly, the case for mobile systems or systems involved in transportation (automotive, railways and aeronautics). One of the most promising issues to improve the compactness of the systems is three-dimensional (3D) integration. The shift from classic power modules (where all the chips are coplanar, and the heat only transferred by the back side) to 3D structures allows improving simultaneously the thermal performances (double sides' cooling), the electric ones (reduction of parasitic inductances and decrease of the resistances) and the electromagnetic ones. Interconnections and assembly, improperly called "packaging", play a fundamental role in this field. In this Thesis, thanks to development of nanotechnologies, a hybrid assembly method is proposed. Named " nano scratch ", it consists in a structure of nano copper wires, deposited on at least one of the surfaces to be joined. The interpenetration of these nanowires is then achieved by pressing the surfaces against each other. Hence, not only a mechanical assembly but also an electrical and a thermal connection is realized. This type of assembly is a promising candidate for the replacements of solder technology. This simple and low cost process may favor 3D integration in power electronics applications. In a first part, the different components of a power module are reminded, Then, a state of art of the different interconnection technologies and assemblies used in power modules is presented. The second chapter focuses on an evaluation of the different methods used to fabricate the nanostructures. Electroplating through a nano porous membrane appears to be the most reproducible one and will be the one studied in this thesis. The last chapter, the principle and implementation of an electro-thermo mechanical assembly are presented and tested. .
Remy, Laurent. "Mise en place d'une nouvelle méthode de conception orientée DFM." Phd thesis, Université de Provence - Aix-Marseille I, 2010. http://tel.archives-ouvertes.fr/tel-00524319.
Full textLauzier, Nicolas. "Mécanismes de sécurité pour l'interaction physique humain-robot : réduction des forces de contact par l'utilisation de limiteurs de couple dans la conception de robots manipulateurs." Thesis, Université Laval, 2011. http://www.theses.ulaval.ca/2011/28505/28505.pdf.
Full textThis thesis presents the analysis, synthesis, optimization, design and experimental validation of safety mechanisms in the context of physical human-robot interaction. In order to improve safety, which is essential to allow the coexistence of humans and robots, an approach based on the design of intrinsically safe manipulators is preferred to collision avoidance and detection systems for reliability reasons. The maximum contact force occuring during a collision is used as a safety criterion due to its simplicity and validity in the context of robotics. For serial robots, it is proposed to place a torque limiter in series with each actuator whereas for suspended robots, it is preferable to separate the base and the effector with a parallel mechanism in which some joints are replaced with torque limiters --- thereby forming a \emph{Cartesian force limiting device}. The use of such mechanisms allows the reduction of the effective manipulator inertia during a collision without affecting the performances under normal conditions. A model is first created in order to compare --- using simulations --- the safety gains obtained with torque limiters with the ones obtained with other articular safety mechanisms when they are implemented alone or in combination with other safety devices. Methods to optimally control the thresholds of adjustable torque limiters placed in series with each actuator of a serial robot are developed. A kinematic performance index is proposed in order to optimize the pose and architecture of such a robot. The approach and the developed methods are experimentally validated using prototypes of adjustable torque limiters based on friction which are placed in series with each actuator of a four-degree-of-freedom robot. Finally, architectures of Cartesian force limiting devices are proposed and optimized and their effectiveness in the context of suspended robots is experimentally validated.
Altuntas, Philippe. "Fabrication et caractérisation de dispositifs de type HEMT de la filière GaN pour des applications de puissance hyperfréquence." Thesis, Lille 1, 2015. http://www.theses.fr/2015LIL10131/document.
Full textGallium Nitride (GaN) based High Electron Mobility Transistors (HEMTs) have emerged as the best candidate for high temperature, high voltage and high power operation in millimeter-wave range. The unique combination of high breakdown field, high electron velocity, and large sheet electron densities of III-N material permits outstanding performance. The work was performed within IEMN laboratory in Microwave Power Devices group. It relates the fabrication and the characterization of GaN HEMT devices for microwave power applications. The first part exposes the physical and electrical properties of gallium nitride as well as a review concerning the state of the art in terms of output power density related to GaN HEMTs. The second chapter deals with the technological processes with a particular attention on the process optimization regarding the ohmic contact and the T-gate technology. Despite outstanding properties, the HEMT performance remains inherently limited by physical and electrical parasitic phenomena. Thus, the third chapter presents the whole studies performed in other to understand these limitation effects (losses, traps, thermal effect). In the last chapter DC, RF, pulsed and large signal measurements are reported for HEMTs based on different heterostructures. In particular, the capability of AlGaN/GaN transistors on Si(111) substrate grown by MBE is demonstrated for high frequency microwave power applications at 40GHz with a continuous wave output power density of 2.7W/mm associated with a power added efficiency of 12.5% and a linear gain of 6.5dB corresponding to the highest saturated power density ever reported on Si(111) substrate to date
Ngoho, Moungoho Stéphane Samuel. "Contribution à la conception de modules hyperfréquences et optoélectroniques intégrés pour des systèmes optiques à très haut débit." Thesis, Limoges, 2016. http://www.theses.fr/2016LIMO0042.
Full textThe increase of the capacities of optical telecommunications systems goes through the development of innovative optoelectronics devices and key technologies with high performances. These devices are subjects to high components integration and the deployed technologies implement complex functions (PDM - QPSK, PDM - 16 QAM etc.). Therefore, it is necessary before any realization to study the electromagnetic behavior of these components in order to predict good performances at high frequency and signal integrity in the transmission chain. Thus, through an EM - circuit modeling, the overall behavior of an electro-optical multilevel modulator based on carrier depletion in a PN junction has been studied and analyzed. The modulator is firstly represented by a model taking in account the junction. The junction is modeled by her equivalents resistance and capacity. Subsequently, the packaging of the modulator with the input and out circuit is realized and optimized. The EM modeling has also helped to design the input circuit of an integrated multiplexer to a 3 bits digital - analog converter for an optical system. The obtained results meet the industry specifications and allow predicting good performances in high frequency for the integrated devices
Aubert, Thierry. "Contribution à l'élaboration de capteurs sans-fil, opérant à très haute température (500-1000º), à base de dispositifs à ondes élastiques de surface : choix des matériaux constitutifs." Thesis, Nancy 1, 2010. http://www.theses.fr/2010NAN10114/document.
Full textSurface acoustic waves devices are key components of telecommunication systems for more than thirty years or so. Because they are passive and very sensitive to external conditions, they also offer the possibility to make autonomous wireless sensors (electronic-less and battery-less), which could be particularly interesting in high-temperature environments. Our work was focused on the choice of materials allowing the fabrication of such sensors for both parts of the device: piezoelectric substrate and metallic electrodes. The latter are generally made of platinum because of the great chemical inertness of this noble metal. Our work allowed us to attribute their degradation, starting around 700°C on, to a phenomenon called agglomeration which is very specific to thin films. This result led us to consider and test more efficient solutions. Regarding the substrate, we mainly studied AlN/Sapphire bilayer structure, promising for such applications but not really studied yet. After the optimization of the deposition parameters of the thin film, realized by reactive magnetron sputtering, leading to the epitaxial quality, we studied the strength of AlN to oxidation under high temperature in air atmosphere. Results given by X-ray diffraction, ellipsometry and secondary ion mass spectroscopy converged to show that AlN/Sapphire structure is a good candidate for such applications at temperatures up to 700°C
Castric, Sébastien. "Méthodes de recalage de modèles et application aux émissions des moteurs diesel." Compiègne, 2007. http://www.theses.fr/2007COMP1696.
Full textSince some decades, European vehicles are subjected to normative laws about pollutant emissions. To face these constraints, car manufacturers have used more and more complex technologies especially for diesel engine cars. This situation has led to a complexification of engine tuning since the numbers of setting parameters has increased too. The present research work was made for the car manufacturer Renault SAS. It aims at proposing methods that allow readjusting models and applications over pollutant models of diesel engine. Renault decided to use techniques of design of experiments, modelling and optimization to solve the problem of diesel engine tuning for emissions. Even if this approach gave good results, it has some drawbacks. The tuning process is composed of loops. Each loop involves hardware changes in the engine. In this case, the model representing the engine’s behaviour, which is a LOLIMOT model, is not valid anymore. Considering that it is not possible to completely rebuild a model, a question appears: “How is it possible to readjust the model after an hardware change by doing as few tests as possible?” This PhD proposes some ways to solve this problem. The first one consists in using the bayesian theory. By using the initial model as an a priori, we created an algorithm permitting to readjust LOLIMOT models. In addition, we proposed a method derived from the first one, and, which aims at using the tuner knowledge about the engine as a prior knowledge. We tested our methods by simulation and owing to tests made on a 2L diesel engine, which was subjected to different hardware changes. In a second time, we considered that even if the Bayesian theory is able to take into account some knowledge, it does not take into account the hardware change characteristics. Thus, we decided to create a new model integrating physical parameters, like, for example, the number of holes in the injectors. We developed a model of diesel combustion. It simulates the evolution of thermodynamic variables inside the combustion chamber even for the multi injection case. Next, we adapted models of pollutants using these variables as inputs. We tested the whole model on prediction of cylinder pressure and pollutants over 2L diesel engine tests
Gstalter, Étienne. "Réduction d’ordre de modèle de crash automobile pour l’optimisation masse / prestations." Thesis, Compiègne, 2020. http://www.theses.fr/2020COMP2576.
Full textThis thesis is a part of a global research work dedicated to reduced-order modelling applications in the Renault engineering direction. It's research topic has been improved in the IRT System)('s project on Reduced Order Model and Multi-disciplinary Optimization. Some previous thesis can help understand the context. ([Vuong], [Charrier]). The main industrial application of the research theme is the focus on a body structure, in a crash loading. Some research works on acoustic, combustion and aerodynamic are currently ongoing. This thesis is both a contribution to the generic ReCUR method, and its application to a car body structure optimization for crash loadings. Engineering teams at Renault uses optimization to obtain the best crash simulation, with a numerical optimization software, based on designs of experiments. It requires a lot of crash simulation because each simulation is considered as unique, with only one response for each parameter. Only Inputs and Outputs are known. The ReCUR method consider that each simulation is a huge mine that needs our attention. We hope that we can decrease the number of crash simulation required to compute a model, by using much more data for each simulation
Avella, Castiblanco Jorge. "Electromagnetic modeling for antenna design and specifications in tunnels of arbitrary cross-section and answering to the electromagnetic constraints of the environment of the railway domain." Thesis, Lille 1, 2013. http://www.theses.fr/2013LIL10189.
Full textThis thesis aims to develop original and appropriate methodologies to model the propagation of EM waves in tunnels of any shape and to propose methodologies to optimize the specification, design and positioning of the antenna in the tunnel. We proposed a novel method for full-wave modal analysis to treat the case of EM wave propagation in structures of large electric dimensions or confined environments of any shape such as tunnels. This method is a modal approach which is based on the 2.5D TLM algorithm and Matrix Pencil algorithm for the discrimination of modes in lossy structures in which the modal density is high and the modes overlap. We considered new boundary conditions called SIBC (Surface Impedance Boundary Condition) for dielectric waveguides with losses. To analyze the general case and several realistic tunnel configurations, we proposed a new classification of modes. Indeed, the classification of existing methods is no longer applicable due to depolarization effects in some realistic cases. A new methodology for determining the specifications and positions of antennas in confined or guided structures was then developed. This methodology is based on a combination of modal analysis and optimization techniques to adjust the weights of the different modes in the tunnel. This approach is used in the case of adaptive antennas, but it has never been applied to the case of multipath propagation modes in the tunnel