Browsing by Author "Sorolla Ayza, Mario"
Now showing 1 - 20 of 64
Results Per Page
Sort Options
Publication Open Access All-metallic ε-near-zero (ENZ) lens based on ultra-narrow hollow rectangular waveguides: experimental results(IEEE, 2014) Orazbayev, Bakhtiyar; Torres Landívar, Víctor; Pacheco-Peña, Víctor; Falcone Lanas, Francisco; Teniente Vallinas, Jorge; Beruete Díaz, Miguel; Sorolla Ayza, Mario; Navarro Cía, Miguel; Engheta, Nader; Ingeniería Eléctrica y Electrónica; Ingeniaritza Elektrikoa eta Elektronikoa; Universidad Pública de Navarra / Nafarroako Unibertsitate PublikoaHere we perform numerical and experimental investigation of plano-concave all-metallic ε-near-zero (ENZ) lens with operational frequency f = 144 GHz. The ENZ lens is achieved by stacking an array of narrow hollow rectangular waveguides working near cut-off frequency. Focusing and radiation properties are numerically analyzed and measured. The enhancement of 5.61 dB and directivity of 17.6 dBi are shown. Good agreement between experimental and numerical results is demonstrated.Publication Open Access Analysis of surface-plasmon-like modes under an engineering perspective(2011) Navarro Cía, Miguel; Beruete Díaz, Miguel; Sorolla Ayza, Mario; Ingeniería Eléctrica y Electrónica; Ingeniaritza Elektrikoa eta ElektronikoaIn this communication we show how one can exploit equivalent circuits to analyze surface-plasmon-like modes (slit and hole arrays, Sievenpiper mushrooms and coaxial hole arrays) and to propose new designs with outstanding features.Publication Open Access Antenas de bocina optimizadas para acoplar modos gaussianos de orden superior(1995) Río Bocio, Carlos del; Gonzalo García, Ramón; Sorolla Ayza, Mario; Thumm, Manfred; Ingeniería Eléctrica y Electrónica; Ingeniaritza Elektrikoa eta ElektronikoaThe concept of higher order free space modes, gaussian-like beam modes can be applied to efficiently transport the power generated by a gyrotron for technological applications. Waveguide modes can be coupled properly to higher order gaussian modes. These modes can be guided by an optimized higher order beam waveguide to the final experiment. A family of optimized non linear horn antennas is investigated in order to maximize the coupling between the guided output modes of a technological gyrotron and the free space modes. The numerical computations show very favourable coupling to higher order gaussian modes, with a conversion effiencies of about 99.8%.Publication Open Access Antenas de ranura sobre planos metálicos(2011) Aliste Álvarez, Francisco José; Beruete Díaz, Miguel; Sorolla Ayza, Mario; Escuela Técnica Superior de Ingenieros Industriales y de Telecomunicación; Telekomunikazio eta Industria Ingeniarien Goi Mailako Eskola Teknikoa; Ingeniería Eléctrica y Electrónica; Ingeniaritza Elektrikoa eta ElektronikoaEste proyecto fin de carrera se centra en el análisis de la radiación y comportamiento de una antena de ranura, así como de la relación existente entre una antena ranurada normal y con corrugaciones. Pretende ofrecer tanto nociones básicas de la teoría de antenas, como un completo estudio de antenas slot tanto teórico como práctico. Se da a conocer en qué consiste una antena y cómo opera, detallando las principales características de las mismas. Se presenta el estudio radioeléctrico, comparando resultados obtenidos de forma simulada con resultados obtenidos de forma práctica, así mismo, se realiza un estudio del comportamiento de la antena cuando aumentamos el plano de masa y le introducimos corrugaciones de diferente geometría. Para finalizar, se ha realizado un estudio en relación al comportamiento que adquiere la antena en función del tipo, profundidad y cantidad de corrugación colocada. Partimos de una antena slot previamente simulada para la frecuencia de 3GHz, aumentado su plano de masa e introduciéndole corrugaciones, para finalmente cambiar el tipo de excitación, por una guía de onda, y ver las mejoras existentes. De todo este proceso, obtenemos muchas conclusiones interesantes, entre las que destacan la mejora de ganancia y directividad de la antena.Publication Open Access Arrangements of via-holes in microstrip lines as metallodielectric periodic structures(Wiley, 2000) Gómez Laso, Miguel Ángel; Lopetegui Beregaña, José María; Bacaicoa, Miguel; Hernández, Jorge; Gonzalo García, Ramón; Sorolla Ayza, Mario; Ingeniería Eléctrica y Electrónica; Ingeniaritza Elektrikoa eta Elektronikoa; Gobierno de Navarra / Nafarroako GobernuaIn this paper, the use of via holes in microstrip lines to design periodic structures that can be regarded as metallodielectric electromagnetic crystals is analyzed. The proposed novel periodic structures achieve a notably increased reflectivity compared to that obtained with a single via hole. Theoretical analysis and experimental results are provided showing a satisfactory performance for these devices as broadband reflectors or short circuits with enhanced behavior at high frequencies.Publication Open Access The beauty of anisotropy in extraordinary transmission fishnet metamaterials(2011) Navarro Cía, Miguel; Beruete Díaz, Miguel; Sorolla Ayza, Mario; Ingeniería Eléctrica y Electrónica; Ingeniaritza Elektrikoa eta ElektronikoaIn this work, we explore both numerically and experimentally, the possibility to obtain positive and negative refraction regimes that depend on the wave polarization, exploiting the strong anisotropy of extraordinary transmission fishnet metamaterials.Publication Open Access Broadband spoof plasmons and subwavelength electromagnetic energy confinement on ultrathin metafilms(Optical Society of America, 2009) Navarro Cía, Miguel; Beruete Díaz, Miguel; Agrafiotis, Spyros; Falcone Lanas, Francisco; Sorolla Ayza, Mario; Maier, Stefan A.; Ingeniería Eléctrica y Electrónica; Ingeniaritza Elektrikoa eta ElektronikoaA complementary split ring resonator (CSRR)-based metallic layer is proposed as a route to mimic surface plasmon polaritons. A numerical analysis of the textured surface is carried out and compared to previous prominent topologies such as metal mesh, slit array, hole array, and Sievenpiper mushroom surfaces, which are studied as well from a transmission line perspective. These well-documented geometries suffer from a narrowband response, alongside, in most cases, metal thickness constraint (usually of the order of λ/4) and non-subwavelength modal size as a result of the large dimensions of the unit cell (one dimensions is at least of the order of λ/2). All of these limitations are overcome by the proposed CSRR-based surface. Besides, a planar waveguide is proposed as a proof of the potential of this CSRR-based metallic layer for spoof surface plasmon polariton guiding. Fundamental aspects aside, the structure under study is easy to manufacture by simple PCB techniques and it is expected to provide good performance within the frequency band from GHz to THz.Publication Open Access Circuit approach to the minimal configuration of terahertz anomalous extraordinary transmission(American Institute of Physics, 2011) Beruete Díaz, Miguel; Navarro Cía, Miguel; Kuznetsov, Sergei A.; Sorolla Ayza, Mario; Ingeniería Eléctrica y Electrónica; Ingeniaritza Elektrikoa eta ElektronikoaIn this letter we present an in-depth circuit analysis of anomalous extraordinary transmission ET through subwavelength slit and hole arrrays loaded by a dielectric slab. We show the key role played by the thickness of the dielectric slab in order to enhance the transmission for TE-polarized waves incident electric field parallel to the slits or to the short in-plane period in hole arrays arranged in rectangular lattice within the cut-off regime of the apertures and to suppress Wood’s anomaly. Analytical and numerical results together with experimental data are presented, showing good agreement among them. This work provides physical insight of the underlying mechanism governing anomalous ET and offers further independent control over orthogonal polarized waves impinging into subwavelength aperture arrays.Publication Open Access Comment on “A waveguide slit array antenna fabricated with subwavelength periodic grooves Appl. Phys. Lett. 91, 143512 (2007)”(AIP Publishing, 2008) Beruete Díaz, Miguel; Falcone Lanas, Francisco; Sorolla Ayza, Mario; Campillo, Igor; Dolado, Jorge S.; Rodríguez Seco, J. E.; Perea, E.; Ingeniería Eléctrica y Electrónica; Ingeniaritza Elektrikoa eta ElektronikoaWe firmly think that it is proven that most of the ideas, results, and discussions presented in C. Huang, C. L. Du, and X. G. Luo, Appl. Phys. Lett. 91, 143512, 2007 were already present in our previous paper (M. Beruete, I. Campillo, J. S. Dolado, J. E. Rodríguez-Seco, E. Perea, F. Falcone, and M. Sorolla, IEEE Trans. Antennas Propag. 54, 340, 2006) and that the antenna design in Huang et al. cannot be considered original at all since it is identical to our design. The only innovative aspect in Huang et al. is the discussion about the multiple slit source.Publication Open Access Comportamiento de propagacion electromagnetica en el apilamiento de agujeros sublambda y agujeros propagantes(2009) Navarro Cía, Miguel; Beruete Díaz, Miguel; Falcone Lanas, Francisco; Campillo, Igor; Sorolla Ayza, Mario; Ingeniería Eléctrica y Electrónica; Ingeniaritza Elektrikoa eta ElektronikoaIn this work, we provide more insight on the physics underlying the transmission through subwavelength hole arrays metaprism by comparing it with propagating hole arrays prism. We show the critical role that the size of the holes plays in this electromagnetic propagation, changing the effective index of refraction from negative to positive values as the hole diameter increases. This causes negative refraction for the zero-th order emerging beam in the metaprism whereas positive refraction in the non-cut-off holes prism. Experimental results (co- and cross-polar measurements) performed at the V-band of the millimeter waves in the Fresnel zone are well supported by numerical analyses in terms of dispersion diagram, spatial electric field distribution and power flow within the prism along with in the output air zone. As expected, higher order diffracted outgoing beams are recorded for the classical prism but not for the metaprism.Publication Open Access Consideraciones de paraxialidad en modos gaussianos de orden superior(1996) Ruiz de la Cuesta, María Teresa; Río Bocio, Carlos del; Gonzalo García, Ramón; Sorolla Ayza, Mario; Ingeniería Eléctrica y Electrónica; Ingeniaritza Elektrikoa eta ElektronikoaUsually, the gaussian beam modes are assumed to be solutions of the wave equation in the free space. Nevertheless, these modes are obtained supposing some paraxial restrictions. Therefore, we will have to check if our working conditions are obeying or not these paraxial restrictions to consider these beam modes as really solutions in free space. In other hand, applications of processing materials, surface coating, etc can use these beam modes to simplify considerably the transmision line between the generator and the final cavity. In this paper, an original study of paraxial considerations for the higher order gaussian modes is presented.Publication Open Access Converging biconcave metallic lens by double-negative extraordinary transmission metamaterial(AIP Publishing, 2009) Navarro Cía, Miguel; Beruete Díaz, Miguel; Sorolla Ayza, Mario; Campillo, Igor; Ingeniería Eléctrica y Electrónica; Ingeniaritza Elektrikoa eta ElektronikoaIn this letter we present simulation and experimental results of a left-handed converging biconcave metallic lens made of stacked subwavelength hole arrays SSHAs working in the millimeter wave range with additional features of polarizer and frequency filter. The converging behavior of the biconcave metallic lens, in contrast with focusing biconvex dielectric lenses, comes as a result of the negative index of refraction that characterizes double-negative metamaterials made of SSHAs. The presented results may find application in the design of lenses and devices both in the microwave, infrared and optical ranges.Publication Open Access Diseño antena microstrip de ranura y antena de parche con geometría fractal(2012) Villar Etxeondo, Víctor Javier; Beruete Díaz, Miguel; Sorolla Ayza, Mario; Escuela Técnica Superior de Ingenieros Industriales y de Telecomunicación; Telekomunikazio eta Industria Ingeniarien Goi Mailako Eskola Teknikoa; Ingeniería Eléctrica y Electrónica; Ingeniaritza Elektrikoa eta ElektronikoaEl Proyecto a realizar consiste en diseñar una antena de ranura con alimentación microstrip, así como una antena parche con geometría fractal, mediante software para posteriormente analizar y evaluar los resultados obtenidos de sus parámetros por medio de simulaciones.Publication Open Access Diseño de guías de onda cuasi-ópticas para modos gaussianos de orden superior(1996) Río Bocio, Carlos del; Sorolla Ayza, Mario; Ingeniería Eléctrica y Electrónica; Ingeniaritza Elektrikoa eta ElektronikoaEn este trabajo se presenta un nuevo método de diseño de guías de onda cuasi-ópticas para modos gaussianos, a frecuencias milimétricas. En concreto, se centrará en la generación de modos gaussianos de orden superior, como posibles candidatos a ser portadores de la energía a través de la línea de transmisión cuasi-óptica. Para lograrlo, se presenta un perfil de antena óptimo para la excitación de modos gaussianos de orden superior, a partir de modos de guía de onda convencional. Este perfil, además de conseguir estructuras gaussianas de alta pureza, adapta óptimamente las estructuras de guías de onda con el espacio libre. La idea de diseño es absolutamente general, por lo que puede ser aplicable a guías de onda rectangulares, ya sean corrugadas o no. El abanico de aplicaciones de este tipo de antenas es muy grande, ya que se pueden utilizar como alimentadoras de líneas de transmisión cuasi-ópticas, como alimentadores de antenas parabólicas para la emisión y/o recepción de señales via satélite, etc. En cuanto al diseño de reflectores, se comprueba la existencia, bajo ciertas condiciones (paraxialidad), de una compatibilidad total de los diseños de guías de onda cuasi-ópticas para modos de orden superior con los diseños clásicos para el modo gaussiano fundamental. Se estudian las estructuras de los modos gaussianos de orden superior, definiendo unos nuevos límites de paraxialidad para estos modos superiores. Finalemente, a modo de validación, se ha podido diseñar, construir y medir, la primera línea cuasi-óptica que utiliza un modo gaussiano de orden superior para transportar la potencia entre un generador de microondas y un aplicador o cavidad final. Se ha obtenido una buena concordancia entre los resultados de la simulación y los medidos experimentalmente.Publication Open Access Diseño óptimo de antenas de bocina multimodo para excitar un haz gaussiano fundamental de alta pureza(1996) Gonzalo García, Ramón; Río Bocio, Carlos del; Teniente Vallinas, Jorge; Sorolla Ayza, Mario; Ingeniería Eléctrica y Electrónica; Ingeniaritza Elektrikoa eta ElektronikoaIn this paper, we present an original and optimal multimode horn antenna design to excite the fundamental Gaussian beam from an overmoded waveguide. In particular, we focus the study in overmoded circular corrugated waveguide. The main idea to design this multimode horn antenna, is to increase the waveguide radius as the desired gaussian mode expands. This principle has also been applied to smooth circular waveguides to excite higher order Gaussian beams from TE0n modes. The horn antenna design considered here, improves the gaussian conversion efficiency, the crosspolarisation and the sidelobes level of some good mixture ( aprox. 85% of TE11 and 15% of TM11 ).Publication Open Access Diseño y simulación de antena plana(2011) Roldán Escolano, Álvaro; Sorolla Ayza, Mario; Escuela Técnica Superior de Ingenieros Industriales y de Telecomunicación; Telekomunikazio eta Industria Ingeniarien Goi Mailako Eskola Teknikoa; Ingeniería Eléctrica y Electrónica; Ingeniaritza Elektrikoa eta ElektronikoaEn este proyecto se describe el diseño, construcción y medida de una antena impresa. La antena se diseñan para sistemas WIFI a 2,45 GHz. El diseño se lleva a cabo con el programa de simulación electromagnética en 3 dimensiones CST Microwave Studio. Para empezar, se diseña, construye y se mide una antena de parche rectangular básica. A continuación se diseña otra antena igual añadiendo unas inserciones en el parche con las que se mejora la adaptación de la antena como se pretendía. Finalmente, se presenta el análisis de los resultados obtenidos, junto con las limitaciones que se han encontrado en la realización de éste proyecto.Publication Open Access Electroinductive waves role in left-handed stacked complementary split rings resonators(Optical Society of America, 2009) Beruete Díaz, Miguel; Aznabet, Mariem; Navarro Cía, Miguel; El Mrabet, O.; Falcone Lanas, Francisco; Aknin, N.; Essaaidi, M.; Sorolla Ayza, Mario; Ingeniería Eléctrica y Electrónica; Ingeniaritza Elektrikoa eta ElektronikoaIn this letter it is presented a Left-Handed Metamaterial design route based upon stacked arrays of screens made of complementary split rings resonators under normal incidence in the microwave regime. Computation of the dispersion diagram highlights the possibility to obtain backward waves provided the longitudinal lattice is small enough. The experimental results are in good agreement with the computed ones. The physics underlying the Left-Handed behavior is found to rely on electroinductive waves, playing the mutual capacitive coupling the major role to explain the phenomenon. Our route to Left-Handed metamaterial introduced in this paper based on stacking CSRRs screens can be scaled to millimeter and terahertz for future applications.Publication Open Access Electromagnetic response of extraordinary transmission plates inspired on Babinet’s principle(InTech, 2011) Navarro Cía, Miguel; Beruete Díaz, Miguel; Sorolla Ayza, Mario; Ingeniería Eléctrica y Electrónica; Ingeniaritza Elektrikoa eta ElektronikoaThis chapter is devoted to polarization effects arisen from perforated metallic plates exhibiting extraordinary transmission (ET). Setting aside the state-of-the-art of perforated metallic plates, we show that by applying Babinet’s principle, subwavelength hole arrays (SHAs) arranged in rectangular lattice can further enhance its potential polarization response. Different perspectives are brought about to describe and understand the particular behaviour of self-complementariness-based SHAs: Babinet’s principle, equivalent circuit analysis, retrieved constitutive parameters, etc. Afterwards, we embark on the numerical analysis of stacked self-complementariness-based perforated plates. It is shown the potential of having a birefringent artificial medium behaving like negative and positive effective refractive index for the vertical and horizontal polarization, respectively. All these findings are experimentally demonstrated at millimetre-waves.Publication Open Access Estudio de la posibilidad de utilizar modos de orden superior en guías de onda cuasi-ópticas(1995) Río Bocio, Carlos del; Gonzalo García, Ramón; Marín Pilz, Miguel; Sorolla Ayza, Mario; Möbius, Arnold; Thumm, Manfred; Ingeniería Eléctrica y Electrónica; Ingeniaritza Elektrikoa eta ElektronikoaThe possibility to employ low power gyrotron tubes (10-30 kW, CW) at millimeter wave frequencies (30-100 GHz) has potential applications in advanced ceramic sintering, surface coating, radar, remote sensing, etc.. In materials processing applications, the final shape of the beam is not relevant, because the experiment have to be done in a cavity which has a metallic mode stirrer in order to obtain inside a uniform distribution of the electromagnetic fields. In this paper, we present a preliminar study, showing that it is possible to use high order modes in the transmission line to carry the power to the final experiment efficiently.Publication Open Access Experimental demonstration of a millimeter-wave metallic ENZ lens based on the energy squeezing principle(IEEE, 2015) Torres Landívar, Víctor; Orazbayev, Bakhtiyar; Pacheco-Peña, Víctor; Teniente Vallinas, Jorge; Beruete Díaz, Miguel; Navarro Cía, Miguel; Sorolla Ayza, Mario; Ingeniería Eléctrica y Electrónica; Ingeniaritza Elektrikoa eta Elektronikoa; Universidad Pública de Navarra / Nafarroako Unibertsitate PublikoaThe performance of an epsilon-near zero (ENZ) plano-concave lens is experimentally demonstrated and verified at the D-band of the millimeter-waves. The lens is comprised of an array of narrow metallic waveguides near cut-off frequency, which effectively behaves as an epsilon-near-zero medium at 144 GHz. A good matching with free space is achieved by exploiting the phenomenon of energy squeezing and a clear focus with a transmission enhancement of 15.9 dB is measured. The lens shows good radiation properties with a directivity of 17.6 dBi and low cross-polar components of -34 dB. All results are supported by numerical simulations.