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 Publikoa
The 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.
Open Access
Nuevas técnicas para el diseño de antenas de bocina corrugadas
(2004) Teniente Vallinas, Jorge; Gonzalo García, Ramón; Río Bocio, Carlos del; Ingeniería Eléctrica y Electrónica; Ingeniaritza Elektrikoa eta Elektronikoa
The present paper deals with the design of modern corrugated horn antennas for extremely low sidelobe level with the use of the well known corrugated Gaussian Profiled Horn Antenna (corrugated GPHA’s) to improve the radiation pattern features and reduce the antenna size. Basic design rules will be given to start with an appropriate profile which can be quickly used as input profile for modern optimization codes to improve antenna characteristics, i.e. its size.
Open Access
Generation of the HE11 mode in rectangular waveguide using gaussian techniques
(IEEE, 1999) Teniente Vallinas, Jorge; Gonzalo García, Ramón; Sorolla Ayza, Mario; Río Bocio, Carlos del; Ingeniería Eléctrica y Electrónica; Ingeniaritza Elektrikoa eta Elektronikoa
A new and efficient design of a rectangular corrugated waveguide mode converter, from TE10 mode in a smooth rectangular monomode waveguide to HE11 mode in a corrugated rectangular waveguide, is proposed. The main idea is the application of Gaussian design techniques, described in the given references, previously applied in circular waveguides. By using these techniques compact and very efficient components are obtained. The obtained far field pattern is rather good as illuminator of square or rectangular parabolic reflectors, with very low sidelobes and crosspolarisation levels, avoiding the use of a rectangular to circular waveguide converter. Simulations by using the HP’s Finite Element code HFSS shown very promising results.
Open Access
Design and characterization of terahertz CORPS beam forming networks
(Springer, 2023) Biurrun Quel, Carlos; Haddad, Thomas; Sievert, Benedikt; Kress, Robin; Weimann, Nils; Erni, Daniel; Rennings, Andreas; Stöhr, Andreas; Teniente Vallinas, Jorge; Río Bocio, Carlos del; Ingeniería Eléctrica, Electrónica y de Comunicación; Institute of Smart Cities - ISC; Ingeniaritza Elektrikoa, Elektronikoaren eta Telekomunikazio Ingeniaritzaren; Universidad Pública de Navarra / Nafarroako Unibertsitate Publikoa
This work reviews the design and applicability of beam-forming networks based on Coherently Radiating Periodic Structures (CORPS-BFN) at Terahertz (THz) frequency bands. These versatile networks offer two operation modes: a continuous beam steering – feeding an antenna array with a linearly progressive phase distribution – using a reduced number of phase controls; or a multi-beam operation, generating independent, overlapped beams. These networks are built upon the concatenation of power combiners/dividers (PCDs) with isolated outputs. The isolation is provided by monolithically integrated resistors, implemented with Ti/TiO thin films for the first time. In this work, a planar prototype of a (inputs/outputs) microstrip CORPS-BFN for operation in the WR3.4/WM-864 band (220–330 GHz) on a thin 50 m Indium Phosphide (InP) substrate is designed, fabricated, and characterized. The measured S-parameters show a reflection coefficient better than -15 dB and an insertion loss between 1.6 and 3.2 dB in the whole band. In addition, an isolation better than 20 dB between the input ports has been measured. An overall remarkable agreement is observed between the measurements and the simulations. Last, the applications, scalability and efficiency of this type of networks at the targeted band are discussed in detail.
Open Access
Generación del modo HE11 a partir de una guía circular lisa monomodo
(1996) Gonzalo García, Ramón; Río Bocio, Carlos del; Teniente Vallinas, Jorge; Sorolla Ayza, Mario; Ingeniería Eléctrica y Electrónica; Ingeniaritza Elektrikoa eta Elektronikoa
In this paper, we present an original taper design to obtain the HE11 corrugated circular waveguide mode exciting with a pure TE11 monomode smooth circular waveguide mode. The proposed corrugated taper has a longitudinal section composed of two hyperbolic profiles in series, one concave and the other convex united at a point, such that the derivative is continuous. Superimposed there is an additional tapering of the corrugation depth that goes from l/2 at taper input to l/4 within the first hyperbola. This original synthesis procedure has been successfully tested by computational simulation. The calculation method has been validated by experimental results of other authors.
Open Access
Low-sidelobe-level millimeter-wave asymmetric bull's eye antenna with minimal profile feeding
(IEEE, 2024) Navarro Cía, Miguel; Beaskoetxea Gartzia, Unai; Teniente Vallinas, Jorge; Beruete Díaz, Miguel; Ingeniería Eléctrica, Electrónica y de Comunicación; Institute of Smart Cities - ISC; Ingeniaritza Elektrikoa, Elektronikoaren eta Telekomunikazio Ingeniaritzaren
Bull’s eye antennas exhibit remarkable directivity considering their low profile, albeit accompanied by high sidelobes. This undesirable radiation characteristic is tackled here by reporting a complementary split ring feeding whereby the broadside space-wave partially responsible for the high sidelobes is cancelled while the leaky wave is excited effectively. This feeding results in an asymmetric bull’s eye antenna with minimal profile (∼ 0.73λ0) and no protrusions on the radiating interface. The fabricated 10-period antenna operating in the Ka-band shows a directivity of 23.5 dBi, a sidelobe level of −22.9 dB (>6 dB improvement compared to other bull’s eye antennas) and a beamwidth of 3.7◦ and 6.7◦ in the E- and H-plane, respectively.
Open Access
Comparación entre antenas cónicas corrugadas y antenas gaussianas corrugadas
(2002) Teniente Vallinas, Jorge; Gonzalo García, Ramón; Río Bocio, Carlos del; Ingeniería Eléctrica y Electrónica; Ingeniaritza Elektrikoa eta Elektronikoa
In this paper, a study of two equal size corrugated horn antennas; a conical and a gaussian profiled horn antenna (GPHA) has been developed. It will be demonstrated that GPHA´s provide lower sidelobes and wider bandwidths, while conical corrugated horn antennas offer higher directivities for the same aperture. Both type of antennas provide low crosspolar levels.
Open Access
The Canfranc Axion Detection Experiment (CADEx): search for axions at 90 GHz with Kinetic Inductance Detectors
(IOP Publishing, 2022) Aja, Beatriz; Arguedas Cuendis, Sergio; Arregui Padilla, Iván; Artal, Eduardo; Barreiro, R. Belén; Casas, Francisco J.; Ory, Marina C. de; Díaz-Morcillo, Alejandro; Fuente, Luisa de la; Gallego, Juan Daniel; García-Barceló, José María; Gimeno, Benito; Gómez, Alicia; Granados, Daniel; Kavanagh, Bradley J.; Gómez Laso, Miguel Ángel; Lopetegui Beregaña, José María; Lozano-Guerrero, Antonio José; Magaz, María T.; Martín-Pintado, Jesús; Martínez-González, Enrique; Miralda-Escudé, Jordi; Monzó-Cabrera, Juan; Najarro de la Parra, Francisco; Navarro-Madrid, José R.; Núñez Chico, Ana B.; Pascual, Juan Pablo; Pelegrin, Jorge; Peña Garay, Carlos; Rodríguez, David; Socuéllamos, Juan M.; Teberio Berdún, Fernando; Teniente Vallinas, Jorge; Vielva, Patricio; Vila, Iván; Vilar, Rocío; Villa, Enrique; Ingeniería Eléctrica, Electrónica y de Comunicación; Institute of Smart Cities - ISC; Ingeniaritza Elektrikoa, Elektronikoaren eta Telekomunikazio Ingeniaritzaren
We propose a novel experiment, the Canfranc Axion Detection Experiment (CADEx), to probe dark matter axions with masses in the range 330–460 μeV, within the W-band (80–110 GHz), an unexplored parameter space in the well-motivated dark matter window of Quantum ChromoDynamics (QCD) axions. The experimental design consists of a microwave resonant cavity haloscope in a high static magnetic field coupled to a highly sensitive detecting system based on Kinetic Inductance Detectors via optimized quasi-optics (horns and mirrors). The experiment is in preparation and will be installed in the dilution refrigerator of the Canfranc Underground Laboratory. Sensitivity forecasts for axion detection with CADEx, together with the potential of the experiment to search for dark photons, are presented.
Open Access
Highly efficient focusing of terahertz waves with an ultrathin superoscillatory metalens: experimental demonstration
(Wiley, 2021-05-06) Legaria Lerga, Santiago; Teniente Vallinas, Jorge; Kuznetsov, Sergei A.; Pacheco-Peña, Víctor; Beruete Díaz, Miguel; Institute of Smart Cities - ISC
The performance of an ultrathin (thickness < 0.04λ 0) metasurface superoscillatory lens (metaSOL) is experimentally demonstrated in the terahertz (THz) range. The metaSOL is designed using two different hexagonal unit cells to improve the efficiency and properties of the conventional transparent–opaque zoning approach. The focusing metastructure produces, at a frequency f exp = 295 GHz, a sharp focal spot 8.9λ exp away from its output surface with a transversal resolution of 0.52λ exp (≈25% below the resolution limit imposed by diffraction), a power enhancement of 18.2 dB, and very low side lobe level (−13 dB). Resolution below the diffraction limit is demonstrated in a broad fractional operation bandwidth of 18%. The focusing capabilities of the proposed metaSOL show its potential use in a range of applications such as THz imaging, microscopy, and communications.
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 Elektronikoa
In 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 ).