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 Publikoa
Here 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.
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 Elektronikoa
In 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.
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 Elektronikoa
In 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.
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 Elektronikoa
We 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.
Open Access
Experimental demonstration of metamaterials application for mitigating scan blindness in phased array antennas
(EDP Sciences, 2016) Rodríguez Ulibarri, Pablo; Crépin, Thomas; Martel, Cédric; Boust, Fabrice; Falcone Lanas, Francisco; Loecker, Claudius; Herbertz, Kai; Bertuch, Thomas; Dousset, Thierry; Martinaud, Jean-Paul; Maci, Stefano; Marcotegui Iturmendi, José Antonio; Beruete Díaz, Miguel; Ingeniería Eléctrica y Electrónica; Ingeniaritza Elektrikoa eta Elektronikoa
This paper presents two metamaterial-inspired solutions to mitigate the scan blindness effects in a phased array antenna. In the ﬁrst solution, portions of a bed of nails are introduced in the radome to prevent the excitation of surface waves. In the second solution, a superstrate metasurface is designed to synthesize a permittivity tensor optimized to achieve a wide angle impedance matching. In both approaches, the numerical simulations are successfully compared with measurements of a phased array antenna prototype with 100 elements. The wire medium-based solution reveals an effective way for reducing the blind-spot in a wide bandwidth, while the metaradome has been found less suitable for the same purpose.
Open Access
Impact of high power interference sources in planning and deployment of wireless sensor networks and devices in the 2.4 GHz frequency band in heterogeneous environments
(MDPI, 2012) López Iturri, Peio; Nazábal Urriza, Juan Antonio; Azpilicueta Fernández de las Heras, Leyre; Rodríguez Ulibarri, Pablo; Beruete Díaz, Miguel; Fernández Valdivielso, Carlos; Falcone Lanas, Francisco; Ingeniería Eléctrica y Electrónica; Ingeniaritza Elektrikoa eta Elektronikoa; Gobierno de Navarra / Nafarroako Gobernua
In this work, the impact of radiofrequency radiation leakage from microwave ovens and its effect on 802.15.4 ZigBee-compliant wireless sensor networks operating in the 2.4 GHz Industrial Scientific Medical (ISM) band is analyzed. By means of a novel radioplanning approach, based on electromagnetic field simulation of a microwave oven and determination of equivalent radiation sources applied to an in-house developed 3D ray launching algorithm, estimation of the microwave oven's power leakage is obtained for the complete volume of an indoor scenario. The magnitude and the variable nature of the interference is analyzed and the impact in the radio link quality in operating wireless sensors is estimated and compared with radio channel measurements as well as packet measurements. The measurement results reveal the importance of selecting an adequate 802.15.4 channel, as well as the Wireless Sensor Network deployment strategy within this type of environment, in order to optimize energy consumption and increase the overall network performance. The proposed method enables one to estimate potential interference effects in devices operating within the 2.4 GHz band in the complete scenario, prior to wireless sensor network deployment, which can aid in achieving the most optimal network topology.
Open Access
Electroinductive waves in chain of complementary metamaterial elements
(AIP Publishing, 2006) Beruete Díaz, Miguel; Falcone Lanas, Francisco; Freire, M. J.; Marqués, R.; Baena, J.D.; Ingeniería Eléctrica y Electrónica; Ingeniaritza Elektrikoa eta Elektronikoa
Electronductive waves supported by chains of resonators drilled on a metallic plate are presented. Propagation of energy comes as a consequence of the electric coupling between these resonators. Therefore, these waves are termed as electroinductive waves. They can be interpreted as the dual counterpart of the so-called magnetoinductive waves, which are due to the mutual inductances along chains of resonators. In order to show their existence, some electromagnetic simulations and experiments have been carried out, using as resonators the complementary particle of the split ring resonator. The reported result opens the way to a high variety of applications in one- and two-dimensional devices, such as transducers, delay lines, bends, power dividers, couplers, antennas, lenses, etc.
Open Access
Response of complementary split ring resonators in composite stratified substrate integrated waveguide
(American Institute of Physics, 2017) Pérez Escudero, José Manuel; Jarauta Ayensa, Eduardo; Falcone Lanas, Francisco; Beruete Díaz, Miguel; Ingeniaritza Elektrikoa eta Elektronikoa; Institute of Smart Cities - ISC; Ingeniería Eléctrica y Electrónica
In this work, the behavior of a Complementary Split Ring Resonator (CSRR) operating within the quasi-static resonance regime and embedded in a composite stratified Substrate Integrated Waveguide (SIW) with two different dielectric layers is analyzed. In these conditions, the propagating modes within the SIW combined with the imposed non-symmetrical structure lead to the excitation of the CSRR elements inside the SIW at difference with conventional excitation. Several cases of CSRR loaded SIW are proposed, and their electromagnetic field components as well as their frequency response are analyzed, providing insight into the CSRR resonance excitation. A test prototype has been designed, fabricated, and measured, showing a good agreement with simulation results and providing a new alternative for the implementation of compact frequency selective devices compatible with planar technology and without undesired radiation loss.
Open Access
Extraordinary transmission and left-handed propagation in miniaturized stacks of doubly periodic subwavelength hole arrays
(Optical Society of America, 2007) Beruete Díaz, Miguel; Sorolla Ayza, Mario; Navarro Cía, Miguel; Falcone Lanas, Francisco; Campillo, Igor; Lomakin, Vitaliy; Ingeniería Eléctrica y Electrónica; Ingeniaritza Elektrikoa eta Elektronikoa
Metallic plates embedded between dielectric slabs and perforated by rectangular arrays of subwavelength holes with a dense periodicity in one of the directions support extraordinary transmission (ET) phenomena, viz. strong peaks in the transmittance frequency dependence. Stacks of such perforated plates support ET phenomena with propagation along the stack axis that is characterized by the left handed behavior. The incorporation of the dielectric materials and dense periodicity allows significantly reducing the illuminated area of the perforated plate required experimentally to observe the ET phenomena as compared to the areas required in the case of free standing rectangular hole arrays. This facilitates the experimental investigation of ET under excitation in the Fresnel zone of Gaussian beams.
Open Access
Ultra-wideband metamaterial filter based on electroinductive-wave coupling between microstrips
(EMW Publishing, 2009) Navarro Cía, Miguel; Carrasco, José Miguel; Beruete Díaz, Miguel; Falcone Lanas, Francisco; Ingeniería Eléctrica y Electrónica; Ingeniaritza Elektrikoa eta Elektronikoa
In this work, we analyse the frequency response of microstrip lines coupled by complementary split ring resonators (CSRRs) etched on the ground plane supporting electroinductive waves (EIWs). The single-particle configurations demonstrate the principle of operation whose bandwidths reach 67% of the central frequency. A double configuration is afterwards investigated as a further improvement of the filtering response, such as the level of the spurious lower frequency band. Finally, an ultimate prototype comprising different CSRRs along the access line, together with the aforementioned EIW-coupling is proposed for filtering undesired higher bands. Experimental results confirm numerical analysis.