Embargo
Experimental validation of a Ku-band dual circularly polarized metasurface antenna
(IEEE, 2018) Tellechea Pereda, Amagoia; Caminita, Francesco; Martini, Enrica; Ederra Urzainqui, Íñigo; Teniente Vallinas, Jorge; Iriarte Galarregui, Juan Carlos; Gonzalo García, Ramón; Maci, Stefano; Ingeniaritza Elektrikoa eta Elektronikoa; Institute of Smart Cities - ISC; Ingeniería Eléctrica y Electrónica
The experimental validation of a Ku-band dual circularly polarized (CP) broadside-beam metasurface (MTS) antenna is presented. A radially modulated anisotropic single layer MTS has been synthesised employing sub-wavelength elliptical slotted metallic patches printed on top of a thin Arlon grounded substrate. In the structure, two decoupled phasematched transverse magnetic and transverse electric surface waves (SWs) are excited, which interact with the modulated surface leading to a CP broadside radiation. Two different orthomode transducers have been designed to excite the SWs with orthogonal polarization and equal amplitude. The first feeding system is composed of a metallic stepped septum inside an airfilled square waveguide. A conical section is included to match the output port of the square waveguide with the terminal, dielectric filled circular waveguide. The second feed is much more compact and efficient and it is composed of a circular waveguide completely filled by a dielectric. Depending on the input port excited on the feeds, two TE11 modes are excited with ±90° phase shift, which determine the right-hand or left-hand sense of the broadside beam generated by the MTS. Manufacturing details of the MTS and excitations are given and the measurements are compared with the simulation results. Finally, conclusions are drawn.
Open Access
New hexagonal CORPS-BFN for multibeam antenna applications
(IEEE, 2020) Biurrun Quel, Carlos; Montesano, Antonio; Ederra Urzainqui, Íñigo; Iriarte Galarregui, Juan Carlos; Río Bocio, Carlos del; Ingeniaritza Elektrikoa, Elektronikoaren eta Telekomunikazio Ingeniaritzaren; Institute of Smart Cities - ISC; Ingeniería Eléctrica, Electrónica y de Comunicación
This work presents a new topology of a Coherently Radiating Periodic Structure - Beam Forming Network (CORPS-BFN) and its application for multibeam systems. A unit cell, consisting of a transition from a coaxial input to an intersection of three strip-lines with an angular span of 120 degrees, is proposed and analysed. A periodical replication of the cell gives rise to a uniform layer, allowing a proper matching of the ports of the network. Stacked layers allow in-phase propagation and distribution of the energy through the structure, increasing the number of output ports with each layer.
Open Access
A wide beamwidth magneto-electric dipole atenna for wide beam scanning antenna arrays
(IEEE, 2024-09-30) Khan, Ihtesham; Zhao, Huiling; Iriarte Galarregui, Juan Carlos; Ederra Urzainqui, Íñigo; Ingeniería Eléctrica, Electrónica y de Comunicación; Ingeniaritza Elektrikoa, Elektronikoa eta Telekomunikazio Ingeniaritza
In this study, a simple and cost-effective configuration to broaden the beamwidths of the patch antenna has been studied. The proposed wide beamwidths antenna consists of two parasitic magnetic dipoles placed orthogonally to a driven electric dipole. Due to the complementary far-field radiation behaviors of both antennas in their respective E-plane and H-plane, the antenna half-power beamwidth broadens. An excellent wide beam of 138.6° and 110.9° in E-plane and H-plane, respectively, has been achieved at 4.72 GHz. The proposed antenna has been fabricated and tested. Measurements shows good agreement with the simulations. The proposed antenna can find its application for the increasing the scanning coverage of the patch antenna arrays.
Open Access
Remote sensing for plant water content monitoring: a review
(MDPI, 2021) Quemada Mayoral, Carlos; Pérez Escudero, José Manuel; Gonzalo García, Ramón; Ederra Urzainqui, Íñigo; Santesteban García, Gonzaga; Torres Molina, Nazareth; Iriarte Galarregui, Juan Carlos; Institute of Smart Cities - ISC; Institute for Multidisciplinary Research in Applied Biology - IMAB
Las redes sociales se han convertido en una de las principales fuentes de información, especialmente entre los más jóvenes. Al mismo tiempo, se ha incrementado la producción y circulación de información falsa o fake news a través de las redes. En este contexto, resulta crucial que los jóvenes adquieran estrategias y competencias para realizar una lectura crítica de la información que consumen. Este estudio busca analizar el comportamiento del alumnado de secundaria ante la información falsa y el efecto de una intervención didáctica, realizada online durante la pandemia de la covid-19, cuyo objetivo era que el alumnado desarrollara competencias para detectar noticias falsas. Se trata de una investigación participativa con un diseño de pre-test y post-test. Los resultados muestran que el alumnado incrementó su competencia para identificar algunos tipos de falsedad como la información no probada y la información tergiversada, si bien tuvo problemas para reconocer información descontextualizada o el uso de lenguaje discriminatorio. Las estrategias que más utilizó son la comprobación de datos en internet y el uso de verificadores. Se observaron comportamientos diferenciados entre el alumnado que identificó la información falsa y el que no lo hizo. Las conclusiones apuntan a la necesidad de trabajar en el aula de forma integral, extensiva y transversal la evaluación de la información partiendo de las habilidades que el alumnado ya posee.
Open Access
EBG superstrate antenna for WAAS bands
(2008) Osés de León, Ángel; Iriarte Galarregui, Juan Carlos; Ederra Urzainqui, Íñigo; Gonzalo García, Ramón; Ingeniería Eléctrica y Electrónica; Ingeniaritza Elektrikoa eta Elektronikoa
Multiband antennas can simplify considerably the complexity of receivers and transmitters, reducing the size and the mass of the conventional configurations. On the other hand, applications with high directivity requirements need array designs to comply with the directivity specifications using conventional technology. EBG superstrate designs have been satisfactory applied to single band applications using a single EBG superstrate layer. The number of number of radiating elements of conventional technology designs are considerably reduced when using EBG technology. Dual band configurations have also been designed in a single layer, but when working frequencies are too close a second EBG layer is needed. A dual layer EBG superstrate which can easily be adjusted to the desired operational frequencies is presented. The design has been realized to comply with the navigation antenna requirements of Wide Area Augmentation system (WAAS) application in L1 and L2 bands.
Open Access
Surface waves of finite size electromagnetic band gap woodpile structures
(EMW Publishing, 2011) Ederra Urzainqui, Íñigo; Iriarte Galarregui, Juan Carlos; Gonzalo García, Ramón; Ingeniería Eléctrica y Electrónica; Ingeniaritza Elektrikoa eta Elektronikoa
This paper studies the surface modes at the interface of finite size Electromagnetic Band Gap (EBG) woodpile structures. The impact of different types of woodpile terminations on the properties of these surface modes is analyzed. For all the studied terminations there exist surface modes which must be taken into account when designing components based on this EBG structure.
Open Access
Design alternatives for a submillimeter-wave Fabry-Perot cavity antenna with a SiGe on-chip feed
(IEEE, 2024-02-17) Iriarte Galarregui, Juan Carlos; Khan, Ihtesham; Herrera-Martin, Juan M.; Urain, Álvaro; Berenguer, Roc; Ederra Urzainqui, Íñigo; González Posadas, Vicente; Segovia-Vargas, Daniel; Ingeniería Eléctrica, Electrónica y de Comunicación; Ingeniaritza Elektrikoa, Elektronikoa eta Telekomunikazio Ingeniaritza; Universidad Pública de Navarra / Nafarroako Unibertsitate Publikoa, PRO-UPNA 11893
In this paper different alternatives for the design of a Fabry-Perot cavity antenna operating in the Sub-mmwave frequency range and fed by a SiGe spiral antenna are evaluated. In particular a single spiral and a sequentially fed array of spiral antennas are compared, showing, due to the losses in the Si substrate the superior performance of the single fed cavity. However, the use of a sequentially rotated array significantly improves the Axial Ratio (AR).
Open Access
A new ABS conductive material to develop fully 3D-printed patch antennas
(IEEE, 2023) Jiménez Peña, Javier; Irigoyen, Joseba; Aresti Bartolomé, Maite; Ederra Urzainqui, Íñigo; Bravo Larrea, Javier; Iriarte Galarregui, Juan Carlos; Ingeniería Eléctrica, Electrónica y de Comunicación; Institute of Smart Cities - ISC; Ingeniaritza Elektrikoa, Elektronikoaren eta Telekomunikazio Ingeniaritzaren
Additive manufacturing technology is rapidly overcoming some of its initial limitations and, thus, creating a very useful engineering option for prototyping complex geometries for a wide range of electronic devices. Based on important advantages such as turn-around, reliability, material waste reduction, and low implementation costs, the technology is being continuously developed and improved. This paper presents a completely 3D-printed microstrip patch antenna to demonstrate the feasibility of a new conductive Acrylonitrile Butadiene Styrene (ABS) material in the fabrication of three-dimensional (3D) antennas using additive manufacturing method. The prototype of the antenna has been fabricated using Raise3D E2 printer, commercial ABS and a new ABS filament developed by Naitec for dielectric and conductive parts of the antenna, respectively. The fabricated antenna is compact and light. Preliminary prototypes and fabrication techniques are presented.
Open Access
Broadband radar cross-section reduction using AMC technology
(IEEE, 2013) Iriarte Galarregui, Juan Carlos; Tellechea Pereda, Amagoia; Martínez de Falcón, José Luis; Ederra Urzainqui, Íñigo; Gonzalo García, Ramón; Maagt, Peter de; Ingeniería Eléctrica y Electrónica; Ingeniaritza Elektrikoa eta Elektronikoa
This paper presents the design, fabrication and characterization of a planar broadband chessboard structure to reduce the radar cross-section (RCS) of an object. The chessboard like configuration is formed by combining two artificial magnetic conductor (AMC) cells. The bandwidth limitations intrinsic to AMC structures are overcome in this work by properly selecting the phase slope versus frequency of both AMC structures. 180 degrees phase difference has been obtained over more than 40% frequency bandwidth with a RCS reduction larger than 10dB. The influence of the incidence angle in the working bandwidth has been performed. A good agreement between simulations and measurements is achieved.
Open Access
Research on metamaterials for antenna applications
(2005) Gonzalo García, Ramón; Ederra Urzainqui, Íñigo; Iriarte Galarregui, Juan Carlos; Martínez Pascual, Beatriz; Sáenz Sáinz, Elena; Cantora Álvarez, Pablo; Maagt, Peter de; Ingeniería Eléctrica y Electrónica; Ingeniaritza Elektrikoa eta Elektronikoa
During the last 20 years a lot of attention has been paid to apply Electromagnetic Band Gap (EBG) technology in different frequency ranges, from microwaves to optics. EBG technology is based on the use of periodic structures to prevent the electromagnetic propagation in certain frequency ranges, known as the bandgap [1]. In the last years the new and revolutionary field of Metamaterials is trying to be applied to similar applications. Although different, both technologies have some similitudes as it has been proven for different authors. For instance when working with EBG structures Left-Handed properties can be obtained in some frequency ranges. In this paper, research efforts focussed on applying EBG technology and the more recent Metamaterials, in particular, left-handed materials, to antenna subsystems at microwave and (sub)millimetre wave frequencies are introduced.