Person:
Ederra Urzainqui, Íñigo

person.page.identifierURI

https://academica-e.unavarra.es/handle/2454/48935

Last Name

Ederra Urzainqui

First Name

Íñigo

person.page.departamento

Ingeniería Eléctrica, Electrónica y de Comunicación

person.page.instituteName

ISC. Institute of Smart Cities

ORCID

0000-0002-0497-1627

person.page.upna

2699

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Now showing 1 - 10 of 17

Open Access
Design of a multifrequency antenna array with the use of left-handed superstrates
(2005) Sáenz Sáinz, Elena; Gonzalo García, Ramón; Ederra Urzainqui, Íñigo; Maagt, Peter de; Ingeniería Eléctrica y Electrónica; Ingeniaritza Elektrikoa eta Elektronikoa
In this paper, the radiation performances of different antenna configuration based on Left-Handed superstrates are presented. First of all, the behaviour of a Left- Handed (LH) unit cell is analysed, showing a resonant response with pass band and stop band frequencies. In order to improve the radiation performances of a single dipole, ie., to increase the directivity and efficiency and to reduce the back radiation, diverse LH superstrates working at the resonant frequency of the dipole are analysed. With these configurations, improvements in terms of directivity higher than 6 dB with efficiency closer to 100 % have been obtained.
Open Access
Planar DNG superstrate for dipole antenna gain enhancement
(2007) Sáenz Sáinz, Elena; Gonzalo García, Ramón; Ederra Urzainqui, Íñigo; Ikonen, Pekka; Tretyakov, Sergei A.; Maagt, Peter de; Ingeniería Eléctrica y Electrónica; Ingeniaritza Elektrikoa eta Elektronikoa
In this paper, a volumetric double-negative (DNG) superstrate based on grids of dipoles and wires for dipole antenna applications is proposed.
Open Access
Decoupling of multifrequency dipole antenna arrays for microwave imaging applications
(Hindawi Publishing Corporation, 2010) Sáenz Sáinz, Elena; Guven, K.; Ozbay, Ekmel; Ederra Urzainqui, Íñigo; Gonzalo García, Ramón; Ingeniería Eléctrica y Electrónica; Ingeniaritza Elektrikoa eta Elektronikoa
The mutual coupling between elements of a multifrequency dipole antenna array is experimentally investigated by S-parameter measurements and planar near-field scanning of the radiated field. A multifrequency array with six dipoles is analyzed. In order to reduce the coupling between dipoles, a planarmetasurface is placed atop the array acting as superstrate. Themutual coupling of the antenna elements in the absence and presence of the superstrate is presented comparatively. Between 3 and 20 dB mutual coupling reduction is achieved when the superstrate is used. By scanning the field radiated by the antennas and far-field measurements of the radiation pattern, it is observed that the superstrate confines the radiated power, increases the boresight radiation, and reduces the endfire radiation.
Open Access
Design of a planar meta-surface based on dipoles and wires for antenna applications
(2006) Sáenz Sáinz, Elena; Gonzalo García, Ramón; Ederra Urzainqui, Íñigo; Maagt, Peter de; Ingeniería Eléctrica y Electrónica; Ingeniaritza Elektrikoa eta Elektronikoa
In this paper, the design of a planar meta-surface based on dipoles and wires is presented. The unit cell is formed by three independent layers, which contain two parallel dipoles and one wire. The behaviour of these elements have been analysed separately as an independent unit cell, i.e., the one dipole unit cell, the two dipoles unit cell and the two dipoles and wire unit cell, by means of the transmission response and the dispersion diagrams. For a normal incident plane wave with the E field parallel to the wires and the H field axial to the dipoles, the electric and magnetic responses are excited producing a pass band behaviour which exhibit negative refractive index. This cell has been used to create meta-surfaces for antenna applications. Two configurations have been analysed; the first one is a superstrate of a dipole antenna with the pass band tuned to the resonant frequency of the dipole. It has been observed that the power goes through the meta-surface and is radiated mainly in boresight direction, which increases the directivity up to 8 dBi and the aperture efficiency of the whole configuration. In the second case, a substrate with the stop band tuned to the pass band of the superstrate and the resonant frequency of the dipole has been added. A directivity higher than 9 dBi with a back radiation of -20 dBi have been obtained.
Open Access
Resultados experimentales de la mejora de potencia radiada por un dipolo mediante un superstrato left-handed
(2006) Sáenz Sáinz, Elena; Gonzalo García, Ramón; Ederra Urzainqui, Íñigo; Maagt, Peter de; Ingeniería Eléctrica y Electrónica; Ingeniaritza Elektrikoa eta Elektronikoa
In this paper a comparison between the measured radiation performances of a single dipole and a dipole with a left handed superstrate based on a finite periodic repetition of a unit cell is presented. First of all the return losses and resonant frequency of the dipole has been measured for different sizes of the superstrate, having a good impedance matching and a decrease in the resonant frequency as the number of cells increase. By using an anechoic chamber and a receiver horn antenna, the power transmitted at boresight has been measured for different frequencies, observing a filtering behaviour due to the resonant characteristic of the superstrate and an improvement of the power transmitted at the resonant frequency of around 3.5 dB. Comparing the H and E plane radiation patterns of a dipole and the dipole with superstrate, more symmetrical and directive radiation patterns can be observed. Finally, a comparison between the simulated and measured aperture efficiency is presented with a good agreement between them.
Open Access
Low profile multi-frequency dipole antenna array based on planar meta-surfaces
(IEEE, 2007) Sáenz Sáinz, Elena; Ikonen, Pekka; Gonzalo García, Ramón; Ederra Urzainqui, Íñigo; Tretyakov, Sergei A.; Maagt, Peter de; Ingeniería Eléctrica y Electrónica; Ingeniaritza Elektrikoa eta Elektronikoa
In this paper, the radiation performance of a low profile multi-frequency dipole antenna array with a planar meta-surface is presented. The meta-surface consists of two closely located parallel grids of short dipoles and one grid of continuous wires in between. By tuning a dipole to the pass band of the superstrate and due to the magnetic dipole moments induced in the unit cells, a uniform illumination is achieved and therefore an enhancement of the directivity. Placing a second meta-surface under the dipole with the stop-band tuned to the working frequency, the back radiation is reduced. By combining low and high resonant-frequency unit cells and tuning dipoles to these frequencies, a double-frequency array is formed.
Open Access
Radiation performances of a multifrequency dipole antenna array with a left handed superstrate
(2005) Sáenz Sáinz, Elena; Gonzalo García, Ramón; Ederra Urzainqui, Íñigo; Maagt, Peter de; Ingeniería Eléctrica y Electrónica; Ingeniaritza Elektrikoa eta Elektronikoa
In this paper, the radiation performances of a multifrequency antenna array (MFAA) which consists of two dipoles (1 and 3) that are radiating at 9.57 GHz and other one (dipole 2) radiating at 11.98 GHz are presented. In order to improve the directivity and to reduce the coupling between the dipoles, a non-uniform Left Handed (LH) superstrate formed by cells of different resonant frequencies has been placed over them. Each dipole is tuned to the resonant frequency of the cells that are on top of it allowing the power transmission and producing a very uniform illumination that enhance the radiation performances of the whole structure. With this configuration, directivity values of 10.1 dB when dipoles 1 and 3 are radiating and 8.1 dB when dipole 2 is radiating have been obtained, with a gap between dipoles of 0.23 0 at resonant frequency of the first dipole and a coupling smaller than - 17 dB.
Open Access
Metamaterials as super-substrate to enhance dipole antenna performances
(2004) Sáenz Sáinz, Elena; Gonzalo García, Ramón; Ederra Urzainqui, Íñigo; Maagt, Peter de; Ingeniería Eléctrica y Electrónica; Ingeniaritza Elektrikoa eta Elektronikoa
In this work, pass band properties of Left Handed Media (LHM) are demonstrated. These properties have been used in order to make a LHM super-substrate that is put over a dipole antenna. This super-substrate is going to determine the characteristics of radiation patterns. Simulation with different types of configurations are presented in order to enhance the features of radiation patterns at bore-sight direction.
Open Access
Enhancement of the power radiated by a dipole antenna at boresight by means of a left handed superstrate
(IEEE, 2006) Sáenz Sáinz, Elena; Ederra Urzainqui, Íñigo; Gonzalo García, Ramón; Maagt, Peter de; Ingeniería Eléctrica y Electrónica; Ingeniaritza Elektrikoa eta Elektronikoa
In this paper a comparison between the measured radiation performances of a single dipole and a dipole with a left handed superstrate based on a finite periodic repetition of a unit cell is presented. First of all the return losses and resonant frequency of the dipole has been measured for different sizes of the superstrate, having a good impedance matching and a decrease in the resonant frequency as the number of cells increase. By using an anechoic chamber and a receiver horn antenna, the power transmitted at boresight has been measured for different frequencies, observing a filtering behaviour due to the resonant characteristic of the superstrate and an improvement of the power transmitted at the resonant frequency of around 3 dB. Comparing the H and E plane radiation patterns of a dipole and the dipole with superstrate, more symmetrical and directive radiation patterns can be observed. Finally, a comparison between the simulated and measured aperture efficiency is presented with a good agreement.
Open Access
Análisis de efecto de un superestrato left-handed en la apertura de una guía rectangular
(2005) Sáenz Sáinz, Elena; Gonzalo García, Ramón; Ederra Urzainqui, Íñigo; Maagt, Peter de; Ingeniería Eléctrica y Electrónica; Ingeniaritza Elektrikoa eta Elektronikoa
In this paper, results showing the experimental verification of the gain improvement of a rectangular waveguide antenna when a left-handed material (LHM) is used as superstrate are presented. The improvement has been characterized by means of measuring the increase of transmission (S21 parameter) obtained when this LHM is placed between two open-ended rectangular waveguide antennas. An average increase of transmission of about 6.5 d.B has been obtained. Besides, improvements in the radiation patterns of a rectangular waveguide with a LH superstrate are analyzed. An enhancement of 3.5 dB in the directivity and a reduction of 15 dB in the back radiation have been obtained.