Análisis modal eficiente de dispositivos pasivos de microondas implementados con guías de sección transversal arbitraria

[EN] The general goal of this thesis is the development of a basic tool for the analysis of passive microwave and millimetre-wave devices used in the new generation of communication systems. In particular, the work is focused on the development of a tool for an efficient and accurate modal characterization of passive devices composed of waveguides with arbitrary cross section. In order to achieve this goal, a method recently arisen and called BI-RME (Boundary Integral - Resonant Mode Expansion) is extended. This method has been revealed as one of the most appropriate, for its high computational efficiency, to characterize waveguides with arbitrary cross section. Regarding the original BI-RME method, this one will improve the precision and the efficiency of the modal solution in presence of circular and elliptic perturbations in the arbitrary waveguide contour. Then, the first work consists on extending the original BI-RME method theory to circular and elliptic geometries including the possibility to connect these two new types of segments (circular and elliptic) with the straight segments used until now in the practical implementation of the method. In order to validate the new developed theory, a set of parameters as the cut-off frequencies, the cut-off wavelengths or the electromagnetic fields of canonical waveguides and arbitrarily shaped waveguides of great practical interest, are calculated. These results are compared with analytical well-known solutions or results published in the literature. Once the electromagnetic modal chart of different arbitrarily shaped waveguides is obtained, the following step is the computation of the coupling integrals between these modes and the ones of the rectangular waveguide that completely surrounds the arbitrary contour. Such integrals are essential for the modal analysis of microwave passive structures involving waveguides with arbitrary cross section. For this purpose, the new extended BI-RME method is included into a software package tool based on the integral equation method, which allows to characterize efficiently waveguide discontinuities by means of inmitance matrices (admittance or impedance). This efficient full-wave analysis method requires the knowledge of the modal chart related to all the waveguides included in the devices under consideration, as well as the coupling integrals between the modes of the two waveguides composing the discontinuity. In the rectangular waveguides case this modal information can be easily obtained in an analytical way. However, when a waveguide or both have arbitrary cross section, the accurate and efficient modal analysis can be obtained by means of the BI-RME method. The use of the integral equation method based on admittance or impedance matrices to characterize devices composed of cascading waveguides is specially advantageous because it leads to a linear system of equations. The coefficients matrix of this linear system presents a banded structure that can be appropriately exploited to increase the computational efficiency associated to the resolution of the aforementioned system, and to reduce considerably the computational cost associated to the analysis of complex devices. Next step is the demonstration that in waveguides with arbitrary cross section and with one or two symmetry axes you can generate, also by means of the BI-RME method, the whole family of waveguide modes, so that they verify a certain fictitious boundary condition of electric or magnetic walls in the symmetry plane, and the advantages regarding the computation of the modes are discussed. Furthermore, those different symmetry families of waveguide modes propagate in an independent way along the structures constituted by a connection of uniform waveguides. This situation can also be exploited to increase in a remarkable way the efficiency of the Computer-Aided-Design (CAD) electromagnetic software packages. Once verified with success the efficiency and precision of the new CAD tool developed by means of the analysis of transitions published in the related technical bibliography, the analysis of really complex passive waveguide devices is performed. Some passive waveguide devices analyzed are for instance a filter with inductive coupling windows and tuning screws, a filter with rounded corners, dual mode filters in circular waveguide with elliptic irises or in elliptic waveguides, an evanescent filter, a low bandpass filter in coaxial waveguide, and finally a new 90º twist component for space applications. The simulated results are totally validated by means of comparison with other data published in the related technical bibliography, or by means of measurements of manufactured prototypes. Finally, the conclusions of this work are extracted and future research lines are outlined. Publications in journal and congress presentations in the framework of this thesis are also indicated.[ES] El objetivo general de esta tesis es el desarrollo de una herramienta b´asica general para el an´alisis de dispositivos pasivos de microondas y ondas milim´etricas usados en la nueva generaci´on de sistemas de comunicaciones. En particular, el trabajo se centra en desarrollar una herramienta para una eficiente y precisa caracterizaci´on modal de dispositivos pasivos constituidos por gu´ıas de onda de secci´on transversal arbitraria. Para cumplir con este objetivo se propone extender un m´etodo surgido recientemente y llamado BI-RME (Boundary Integral - Resonant Mode Expansion, que en espa˜nol significa Integral de Contorno - Expansi´on Modal Resonante). Este m´etodo se ha revelado como uno de los m´as adecuados, por su tremenda eficiencia computacional, para caracterizar modalmente las gu´ıas de secci´on transversal arbitraria. Respecto al m´etodo BI-RME original se pretende mejorar la precisi´on y la eficiencia en presencia de perturbaciones circulares y el´ıpticas en el contorno de las gu´ıas a estudiar. El primer trabajo de la tesis consiste entonces en extender la teor´ıa del m´etodo BI-RME a geometr´ıas circulares y el´ıpticas incluyendo la posibilidad de conectar estos dos nuevos tipos de arcos (circulares y el´ıpticos) con los tramos rectos usados hasta ahora en la implementaci´on pr´actica del m´etodo. Con el objeto de validar la nueva teor´ıa desarrollada se calcula un conjunto de par´ametros, como las frecuencias de corte, la longitud de onda de corte o el campo electromagn´etico, que caracterizan gu´ıas can´onicas y gu´ıas arbitrarias de inter´es pr´actico, y se comparan los resultados obtenidos con las soluciones anal´ıticas conocidas o resultados publicados en la literatura. Una vez obtenida la carta modal de las diferentes gu´ıas de secci´on transversal arbitraria, el paso siguiente es calcular las integrales de acoplo entre estos modos y los modos de la gu´ıa rectangular que encierra completamente el contorno arbitrario. Tales integrales son fundamentales para el an´alisis modal de estructuras pasivas de microondas constituidas por transiciones planares entre gu´ıas de secci´on transversal distinta. Para estudiar estas estructuras pasivas, se integra la nueva y extendida t´ecnica BI-RME propuesta en una herramienta inform´atica basada en el m´etodo de la ecuaci´on integral, el cual permite caracterizar eficientemente transiciones planares mediante matrices de inmitancia (admitancia o impedancia). Este m´etodo de an´alisis electromagn´etico full-wave necesita el espectro modal de cada una de las gu´ıas que forman las transiciones, as´ı como las integrales de acoplo entre los modos de las dos gu´ıas adyacentes que constituyen la discontinuidad. En el caso de gu´ıas rectangulares, dicha informaci´on modal se puede obtener f´acilmente de forma anal´ıtica. Sin embargo cuando una gu´ıa o las dos tienen una secci´on transversal arbitraria, esta informaci´on se puede obtener de forma eficiente y precisa mediante el m´etodo BI-RME. El empleo del m´etodo de la ecuaci´on integral basado en matrices de admitancias o de impedancias para caracterizar dispositivos integrados por gu´ıas conectadas en cascada resulta especialmente ventajoso, pues conduce a un sistema de ecuaciones lineales a resolver cuya matriz de coeficientes presenta una estructura en banda, caracter´ıstica que puede explotarse adecuadamente para incrementar la eficiencia computacional asociada a la resoluci´on del citado sistema, y reducir considerablemente el coste asociado al an´alisis de dispositivos complejos. A continuaci´on se demuestra como en gu´ıas de secci´on transversal arbitraria con uno o dos ejes de simetr´ıa se puede generar, tambi´en mediante el m´etodo BI-RME, toda la familia de modos de dicha gu´ıa de manera que verifiquen una cierta condici´on de contorno ficticia de pared el´ectrica o pared magn´etica en el plano de simetr´ıa, y se discuten las ventajas computacionales respecto a calcular todos los modos simult´aneamente. Adem´as, las distintas familias de simetr´ıa se propagan de forma independiente a lo largo de estructuras constituidas por una conexi´on en cascada de gu´ıas uniformes que presentan la misma simetr´ıa. Dicha situaci´on se puede explotar para aumentar de forma notable la eficiencia del simulador electromagn´etico. Verificada con ´exito la eficiencia y precisi´on de la nueva herramienta inform´atica desarrollada mediante el an´alisis de transiciones publicadas en la bibliograf´ıa t´ecnica relacionada, se analizan dispositivos pasivos realmente complejos, tales como un filtro con ventanas de acoplo inductivas y tornillos de sinton´ıa, un filtro con esquinas redondeadas, filtros de modo dual en gu´ıa circular con iris el´ıpticos o en gu´ıa el´ıptica, un filtro de modo evanescente, un filtro paso bajo en gu´ıa coaxial, y finalmente un nuevo girador de polarizaci´on de 90o para aplicaciones espaciales. Los resultados son completamente validados mediante comparaci´on con otros publicados en la bibliograf´ıa t´ecnica relacionada, o bien mediante las medidas de las respuestas asociadas a unas implementaciones pr´acticas de las estructuras analizadas. Finalmente se extraen las conclusiones de la tesis y se indican posibles l´ıneas de investigaci´on futuras. Se indican tambi´en las publicaciones en revistas y las comunicaciones en congresos a que ha dado lugar el trabajo desarrollado en el marco de esta tesis.[CA] L’objectiu general d’esta tesi ´es el desenrotllament d’una ferramenta b`asica general per a l’an`alisi de dispositius passius de microones i ones mil·lim`etriques usats en la nova generaci´o de sistemes de comunicacions. En particular, el treball se centra en desenrotllar una ferramenta per a una eficient i precisa caracteritzaci´o modal de dispositius passius constitu¨ıts per guies d’ona de secci´o transversal arbitr`aria. Per a complir amb este objectiu es proposa estendre un m`etode sorgit recentment i anomenat BI-RME (Boundary Integral - Resonant Mode Expansion, que en valenci`a significa Integral de Contorn - Expansi´o Modal Ressonant). Este m`etode s’ha revelat com un dels mes adequats, per la seua tremenda efici`encia computacional, per a caracteritzar modalment les guies de secci´o transversal arbitr`aria. Respecte al m`etode BI-RME original es pret´en millorar la precisi´o i l’efici`encia en pres`encia de pertorbacions circulars i el·l´ıptiques en el contorn de les guies a estudiar. El primer treball de la tesi consistix aleshores a estendre la teoria del m`etode BI-RME a geometries circulars i el·l´ıptiques incloent la possibilitat de connectar estos dos nous tipus d’arcs (circulars i el·l´ıptics) amb els trams rectes usats fins ara en la implementaci´o pr`actica del m`etode. Amb l’objecte de validar la nova teoria desenrotllada es calcula un conjunt de par`ametres, com les freq¨ u`encies de tall, la longitud d’ona de tall o el camp electromagn`etic, que caracteritzen guies can`oniques i guies arbitr`aries d’inter´es pr`actic, i es comparen els resultats obtinguts amb les solucions anal´ıtiques conegudes o resultats publicats en la literatura. Una vegada obtinguda la carta modal de les diferents guies de secci´o transversal arbitr`aria, el pas seg¨uent ´es calcular les integrals d’acoblament entre estos modes i els modes de la guia rectangular que tanca completament el contorn arbitrari. Tals integrals s´on fonamentals per a l’an`alisi modal d’estructures passives de microones constitu¨ıdes per transicions planars entre guies de secci´o transversal distinta. Amb eixa finalitat, s’integra la nova i estesa t`ecnica BI-RME proposta en una ferramenta inform`atica basada en el m`etode de l’equaci´o integral, el qual permet caracteritzar eficientment transicions planars per mitj`a de matrius d’inmit`ancia (admit`ancia o imped`ancia). Este m`etode d’an`alisi electromagn`etica full-wave necessita l’espectre modal de cadascuna de les guies que formen les transicions, aix´ı com les integrals d’acoblament entre els modes de les dos guies adjacents que constitu¨ıxen la discontinu¨ıtat. En el cas de guies rectangulars, dita informaci´o modal es pot obtindre f`acilment de forma anal´ıtica. No obstant quan una guia o les dos tenen una secci´o transversal arbitr`aria, esta informaci´o es pot obtindre de forma eficient i precisa per mitj` a del m`etode BI-RME. L’us del m`etode de l’equaci´o integral basat en matrius d’admit`ancies o d’imped`ancias per a caracteritzar dispositius integrats per guies connectades en cascada resulta especialment avantatj´os, perqu`e condu¨ıx a un sistema d’equacions lineals a resoldre la matriu de coeficients del qual presenta una estructura en banda, caracter´ıstica que pot explotar-se adequadament per a incrementar l’efici`encia computacional associada a la resoluci´o del citat sistema, i reduir considerablement el cost associat a l’an`alisi de dispositius complexos. A continuaci´o es demostra com en guies de secci´o transversal arbitr`aria amb un o dos eixos de simetria es pot generar, tamb´e per mitj`a del m`etode BI-RME, tota la fam´ılia de modes de dita guia de manera que verifiquen una certa condici´o de contorn fict´ıcia de paret el`ectrica o paret magn`etica en el pla de simetria, i es discutix els avantatges computacionals respecte a calcular tots els modes simult`aniament. A m´es, les distintes fam´ılies de simetria es propaguen de forma independent al llarg d’estructures constitu¨ıdes per una connexi´o en trencada de guies uniformes que tenen les meteixes propietats de simetria. La dita situaci´o es pot explotar per a augmentar de forma notable l’efici`encia del simulador electromagn`etic. Verificada amb `exit l’efici`encia i precisi´o de la nova ferramenta inform`atica desenrotllada per mitj`a de l’an`alisi de transicions publicades en la bibliografia t`ecnica relacionada, s’analitzen dispositius passius realment complexos, tals com un filtre amb finestres d’acoblament inductives i tornels de sintonia, un filtre amb cantons arredonits, filtres de modo dual en guia circular amb iris el·l´ıptics o en guia el·l´ıptica, un filtre de modo evanescent, un filtre pas baix en guia coaxial, i finalment un nou girador de polaritzaci´o de 90o per a aplicacions espacials. Els resultats s´ on completament validats per mitjanc¸ant la comparaci´o amb altres publicats en la bibliografia t` ecnica relacionada, o b´e per mitj`a de les mesures de les respostes associades a unes implementacions pr`actiques de les estructures analitzades. Finalment s’extrauen les conclusions de la tesi i s’indiquen possibles l´ınies d’investigaci´o futures. S’indiquen tamb´e les publicacions en revistes i les comunicacions en congressos a qu`e ha donat lloc el treball desenrotllat en el marc d’esta tesi.Marini, S. (2005). Análisis modal eficiente de dispositivos pasivos de microondas implementados con guías de sección transversal arbitraria [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/13173

Methodology based on collaborative problem solving implemented in a high academic achievement group

[EN] The High Academic Achievement (ARA, by its acronym in Spanish) group began its course in the 2011/12 academic year to reinforce the potential of the most outstanding students since the beginning of their university studies. In order to improve the employability of this students, at least 50% of basic or compulsory credits of the degree are taught in English. In addition, a series of language training aids are provided, which also has advantages in obtaining Erasmus scholarships. The ARA group only offers 25 places each academic course. Being a small group, personalized teaching is enhanced while the schedule is compacted. In this contribution the methodology used in the subject of Signals and Systems of the Degree in Sound and Image in Telecommunication Engineering of the Alicante University (Spain) is presented. The methodology emphasizes the practical application of the subject and its direct applicability in real systems.Ferrando-Rocher, M.; Marini, S.; Galiana-Merino, J.; Carbajo, J. (2020). Methodology based on collaborative problem solving implemented in a high academic achievement group. En 6th International Conference on Higher Education Advances (HEAd'20). Editorial Universitat Politècnica de València. (30-05-2020):555-560. https://doi.org/10.4995/HEAd20.2020.11105OCS55556030-05-202

A Ka-band Compact Single-Layer Gap Waveguide Monopulse Slot Array Antenna

[EN] This paper presents a gap-waveguide-based compact monopulse array antenna for millimeter-wave tracking applications at Ka-band (27.5 to 30.5 GHz). A low-loss Magic-Tee is designed to be used in a monopulse comparator network. The gap waveguide planar monopulse comparator network is integrated in a single layer with a 2×2 corporate-fed network combining ridge gap and groove gap waveguides. Simulated results show bandwidths of 10% with input reflection coefficients better than ¿12 dB for the sum and difference ports over the frequency band of interest. Besides, the isolation between sum and difference ports is more than 50 dB. The simplicity of the design and the fact that it is housed in a single layer permit easy scaling to larger arrays.This work has been funded by the Spanish Ministry of Science and Innovation under projects PID2019-107688RBC22 and PID2019-103982RB-C43.Ferrando-Rocher, M.; Mayor, B.; Marini, S.; Valero-Nogueira, A.; Herranz Herruzo, JI. (2021). A Ka-band Compact Single-Layer Gap Waveguide Monopulse Slot Array Antenna. IEEE. 1-3. http://hdl.handle.net/10251/1910641

Ultrafast nonlinear optical response of Dirac fermions in graphene

The speed of solid-state electronic devices, determined by the temporal dynamics of charge carriers, could potentially reach unprecedented petahertz frequencies through direct manipulation by optical fields, consisting in a million-fold increase from state-of-the-art technology. In graphene, charge carrier manipulation is facilitated by exceptionally strong coupling to optical fields, from which stems an important back-action of photoexcited carriers. Here we investigate the instantaneous response of graphene to ultrafast optical fields, elucidating the role of hot carriers on sub-100 fs timescales. The measured nonlinear response and its dependence on interaction time and field polarization reveal the back-action of hot carriers over timescales commensurate with the optical field. An intuitive picture is given for the carrier trajectories in response to the optical-field polarization state. We note that the peculiar interplay between optical fields and charge carriers in graphene may also apply to surface states in topological insulators with similar Dirac cone dispersion relations.Peer ReviewedPostprint (published version

Fundamental material properties of the 2LiBH4-MgH2 reactive hydride composite for hydrogen storage: (II) Kinetic properties

Reaction kinetic behaviour and cycling stability of the 2LiBH4-MgH2 reactive hydride composite (Li-RHC) are experimentally determined and analysed as a basis for the design and development of hydrogen storage tanks. In addition to the determination and discussion about the properties; different measurement methods are applied and compared. The activation energies for both hydrogenation and dehydrogenation are determined by the Kissinger method and via the fitting of solid-state reaction kinetic models to isothermal volumetric measurements. Furthermore, the hydrogen absorption-desorption cycling stability is assessed by titration measurements. Finally, the kinetic behaviour and the reversible hydrogen storage capacity of the Li-RHC are discussed.Fil: Jepsen, Julian. Helmholtz-Zentrum Geesthacht Zentrum für Material- und Küstenforschung; AlemaniaFil: Milanese, Chiara. Università degli Studi di Pavia; ItaliaFil: Puszkiel, Julián Atilio. Comisión Nacional de Energía Atómica. Centro Atómico Bariloche; Argentina. Helmholtz-Zentrum Geesthacht Zentrum für Material- und Küstenforschung; Alemania. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte; ArgentinaFil: Girella, Alessandro. Università degli Studi di Pavia; ItaliaFil: Schiavo, Benedetto. Università degli Studi di Palermo; ItaliaFil: Lozano, Gustavo A.. Helmholtz-Zentrum Geesthacht Zentrum für Material- und Küstenforschung; AlemaniaFil: Capurso, Giovanni. Helmholtz-Zentrum Geesthacht Zentrum für Material- und Küstenforschung; AlemaniaFil: Von Colbe, José M. Bellosta. Helmholtz-Zentrum Geesthacht Zentrum für Material- und Küstenforschung; AlemaniaFil: Marini, Amedeo. Comisión Nacional de Energía Atómica. Centro Atómico Bariloche; ArgentinaFil: Kabelac, Stephan. Leibniz Universität Hannover; AlemaniaFil: Dornheim, Martin. Helmholtz-Zentrum Geesthacht Zentrum für Material- und Küstenforschung; AlemaniaFil: Klassen, Thomas. Helmholtz-Zentrum Geesthacht Zentrum für Material- und Küstenforschung; Alemani

Practical Design of Filters Using EBG Waveguides Periodically Loaded with Metal Ridges

[EN] The dispersion diagram of infinite periodic structures is useful for the practical design of waveguide filters. Starting from the dispersion diagram of a unit cell, it is possible to generate a finite structure with very similar pass- and stop-bands (gaps). However, truncation of the infinite periodic structure degrades the pass-band performance. In this paper, these impairments are overcome by means of suitable waveguide tapers matching the impedance of the periodic structure to the access ports. As a result, the design of practical low-pass filters, derived from passive structures based on Electromagnetic Band-Gap (EBG) waveguides periodically loaded with metal ridges, is successfully addressed. According to this procedure, a five-order and an eight-order EBG low-pass filters are obtained after an optimization step. Measurements of a manufactured prototype fully validate the proposed approach.This work was supported by the Ministerio de Economía y Competitividad (MINECO), Spanish Government, under the R&D projects TEC2013-47037-C5-1-R and TEC2013-47037-C5-4-R. The authors would like to thank ITACA (Instituto de Aplicaciones de las Tecnologías y de las Comunicaciones Avanzadas), from Technical University of Valencia (Valencia, Spain), for their support in the accurate manufacturing of the low-pass filter prototypeMarini, S.; Soto Pacheco, P.; Coves, A.; Gimeno Martinez, B.; Boria Esbert, VE. (2016). Practical Design of Filters Using EBG Waveguides Periodically Loaded with Metal Ridges. Progress in ElectromagneticsResearch C. Pier C. 63:13-21. https://doi.org/10.2528/PIERC15111603S13216

Ejemplo práctico de diseño de un filtro en iris rectangular empleando tecnología SIW para laboratorios docentes

Comunicación presentada en el XXIX Simposium Nacional de la Unión Científica Internacional de Radio, URSI 2014, Valencia, Septiembre 2014.This paper presents the design and practical implementation of a waveguide-based microwave filter in Substrate Integrated Waveguide (SIW) technology. The use of SIW technology for implementing waveguide filters makes the presented design specially aimed for being used in undergraduate courses related to microwave engineering and filter designing. Their low cost and easiness from the filter fabrication point of view allows their use in microwave laboratory courses where students can implement their own theoretical filter designs and measure their frequency response

Fundamental material properties of the 2LiBH4-MgH2 reactive hydride composite for hydrogen storage: (I) Thermodynamic and heat transfer properties

Thermodynamic and heat transfer properties of the 2LiBH4-MgH2 composite (Li-RHC) system are experimentally determined and studied as a basis for the design and development of hydrogen storage tanks. Besides the determination and discussion of the properties, different measurement methods are applied and compared to each other. Regarding thermodynamics, reaction enthalpy and entropy are determined by pressure-concentration-isotherms and coupled manometric-calorimetric measurements. For thermal diffusivity calculation, the specific heat capacity is measured by high-pressure differential scanning calorimetry and the effective thermal conductivity is determined by the transient plane source technique and in situ thermocell. Based on the results obtained from the thermodynamics and the assessment of the heat transfer properties, the reaction mechanism of the Li-RHC and the issues related to the scale-up for larger hydrogen storage systems are discussed in detail.Fil: Jepsen, Julian. Helmholtz-Zentrum Geesthacht; AlemaniaFil: Milanese, Chiara. University of Pavia; ItaliaFil: Puszkiel, Julián Atilio. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Comisión Nacional de Energía Atómica. Centro Atómico Bariloche; Argentina. Helmholtz-Zentrum Geesthacht; AlemaniaFil: Girella, Alessandro. University of Pavia; ItaliaFil: Schiavo, Benedetto. Universidad de Palermo; Argentina. Istituto per le Tecnologie Avanzate; ItaliaFil: Lozano, Gustavo A.. Helmholtz-Zentrum Geesthacht; Alemania. BASF; AlemaniaFil: Capurso, Giovanni. Helmholtz-Zentrum Geesthacht; AlemaniaFil: Von Colbe, José M. Bellosta. Helmholtz-Zentrum Geesthacht; AlemaniaFil: Marini, Amedeo. University of Pavia; ItaliaFil: Kabelac, Stephan. Leibniz Universität Hannover; AlemaniaFil: Dornheim, Martin. Helmholtz-Zentrum Geesthacht; AlemaniaFil: Klassen, Thomas. Helmholtz-Zentrum Geesthacht; Alemani

Efficient full-wave modal analysis of waveguides with arbitrary geometry defined by straight, circular and elliptical segments

Many modern waveguide devices, such as dual-mode filters and diplexers, can be modelled considering the whole circuit as a cascade of waveguide step discontinuities. Most of such discontinuities usually involve waveguides with arbitrary cross-section defined by linear, circular and/or elliptical segments. A fast and accurate procedure for the full-wave modal characterization of such arbitrarily shaped waveguides is based on the Boundary Integral— Resonant Mode Expansion (BI-RME) technique well described in [1]. In this paper, we present a very efficient implementation of a full-wave modal analysis tool for arbitrarily shaped waveguides based on the BI-RME theory.This work was supported by the European Commission under the Research and Training Networks Programme, Contract No. HPRN-CT-2000-00043

Full-wave analysis and applications of EBG waveguides periodically loaded with metal ridges

In this paper, a fast and accurate full-wave analysis tool of passive structures based on Electromagnetic-Bandgap (EBG) waveguides periodically loaded with metal ridges is proposed. For this purpose, a very efficient Integral Equation (IE) technique is followed to model the planar steps involving arbitrary waveguides. The well-known Boundary Integral - Resonant Mode Expansion (BI-RME) method is used to obtain the modal chart of the ridged waveguides. In order to show the advantages of this tool, a periodically loaded E-plane filter with improved stopband performance is analyzed and compared to standard implementation. Dispersion relations are also derived and used as guidelines for designing an EBG fifth-order low-pass filter