Envíos recientes

  • Design of MOS-translinear multiplier/dividers in analog VLSI 

    López Martín, Antonio; Carlosena García, Alfonso (Hindawi Publishing Corporation, 2000)   Artículo / Artikulua
    A general framework for designing current-mode CMOS analog multiplier/divider circuits based on the cascade connection of a geometric-mean circuit and a squarer/ divider is presented. It is shown how both building blocks ...
  • Effect of the glottal source and the vocal tract on the partials amplitude of vibrato in male voices 

    Arroabarren Alemán, Ixone; Carlosena García, Alfonso (Acoustical Society of America, 2006)   Artículo / Artikulua
    In this paper the production of vocal vibrato is investigated. The most relevant features of the acoustical vibrato signal, frequency and amplitude variations of the partials, will be related to the voice production ...
  • Metasurface-based ultrathin carpet cloaks for millimeter waves 

    Orazbayev, Bakhtiyar; Mohammadi Estakhri, Nasim; Alù, Andrea; Beruete Díaz, Miguel (2017)   Artículo / Artikulua
    A metasurface carpet cloak for millimetre-wave range with polarization independent performance is experimentally demonstrated. It is shown that the cloak is able to mimic the ground plane by fully restoring the amplitude ...
  • 3D-printed 96 GHz bull’s-eye antenna with off-axis beaming 

    Beaskoetxea Gartzia, Unai; Maci, Stefano; Navarro Cía, Miguel; Beruete Díaz, Miguel (IEEE, 2017)   Artículo / Artikulua
    Reducing the profile, footprint and weight of antennas embarked on aircrafts, drones or satellites has been a long pursued objective. Here we tackle this issue by developing a millimeter-wave 96 GHz elliptical Bull’s-Eye ...
  • Diffusive-light invisibility cloak for transient illumination 

    Orazbayev, Bakhtiyar; Beruete Díaz, Miguel; Martínez, Alejandro; García Meca, Carlos (American Physical Society, 2016)   Artículo / Artikulua
    Invisibility in a diffusive-light-scattering medium has been recently demonstrated by employing a scattering-cancellation core-shell cloak. Unlike nondiffusive cloaks, such a device can be simultaneously macroscopic, ...
  • Experimental demonstration of metasurface-based ultrathin carpet cloaks for millimetre waves 

    Orazbayev, Bakhtiyar; Mohammadi Estakhri, Nasim; Alù, Andrea; Beruete Díaz, Miguel (Wiley, 2016)   Artículo / Artikulua
    A metasurface carpet cloak for millimeter-wave range with polarization-independent performance is experimentally demonstrated. It is shown that the cloak is able to mimic the ground plane by fully restoring the amplitude ...
  • Polarization diversity scheme for BOTDA sensors based on a double orthogonal pump interaction 

    Urricelqui Polvorinos, Javier; López Fernandino, Felipe; Sagüés García, Mikel; Loayssa Lara, Alayn (IEEE, 2015)   Artículo / Artikulua
    We introduce a Brillouin optical time domain analysis (BOTDA) sensor deploying a novel polarization diversity technique based on the use of two orthogonal pump pulses which simultaneously interact with a phase modulated ...
  • Synthesis of Brillouin frequency shift profiles to compensate non-local effects and Brillouin induced noise in BOTDA sensors 

    Urricelqui Polvorinos, Javier; Sagüés García, Mikel; Loayssa Lara, Alayn (Optical Society of America, 2014)   Artículo / Artikulua
    We present a novel technique for Brillouin optical time domain analysis (BOTDA) sensors that simultaneously compensates non local effects and reduces Brillouin noise. The technique relies on the wavelength modulation of ...
  • Phasorial differential pulse-width pair technique for long-range Brillouin optical time-domain analysis sensors 

    Urricelqui Polvorinos, Javier; Sagüés García, Mikel; Loayssa Lara, Alayn (Optical Society of America, 2014)   Artículo / Artikulua
    We introduce a novel phasorial differential pulse width pair (PDPP) method for Brillouin optical time domain analysis (BOTDA) sensors that combines spatial resolution enhancement with increased tolerance to non local ...
  • BOTDA measurements tolerant to non-local effects by using a phase-modulated probe wave and RF demodulation 

    Urricelqui Polvorinos, Javier; Sagüés García, Mikel; Loayssa Lara, Alayn (Optical Society of America, 2013)   Artículo / Artikulua
    We demonstrate a Brillouin optical time domain analysis sensor based on a phase modulated probe wave and RF demodulation that provides measurements tolerant to frequency dependent variations of the pump pulse power induced ...
  • Dynamic BOTDA measurements based on Brillouin phase-shift and RF demodulation 

    Urricelqui Polvorinos, Javier; Zornoza Indart, Ander; Sagüés García, Mikel; Loayssa Lara, Alayn (Optical Society of America, 2012)   Artículo / Artikulua
    We demonstrate a novel dynamic BOTDA sensor based, for the first time to our knowledge, on the use of the Brillouin phase shift in addition to the conventional Brillouin gain. This provides the advantage of measurements ...
  • Overcoming non-local effects and Brillouin threshold limitations in Brillouin optical time domain sensors 

    Ruiz Lombera, Rubén; Urricelqui Polvorinos, Javier; Sagüés García, Mikel; Mirapeix, Jesús; López Higuera, José Miguel; Loayssa Lara, Alayn (IEEE, 2015)   Artículo / Artikulua
    We demonstrate, for the first time to our knowledge, a Brillouin optical time domain analysis (BOTDA) sensor that is able to operate with a probe power larger than the Brillouin threshold of the deployed sensing fiber ...
  • Brillouin optical time-domain analysis sensor assisted by Brillouin distributed amplification of pump pulses 

    Urricelqui Polvorinos, Javier; Sagüés García, Mikel; Loayssa Lara, Alayn (Optical Society of America, 2015)   Artículo / Artikulua
    We demonstrate the extension of the measurement range of Brillouin optical time-domain analysis (BOTDA) sensors using a distributed Brillouin amplifier (DBA). The technique is based on injecting a DBA pump wave in the ...
  • Cost-effective Brillouin optical time-domain analysis sensor using a single optical source and passive optical filtering 

    Iribas Pardo, Haritz; Urricelqui Polvorinos, Javier; Mariñelarena Ollacarizqueta, Jon; Sagüés García, Mikel; Loayssa Lara, Alayn (Hindawi Publishing Corporation, 2016)   Artículo / Artikulua
    We present a simplified configuration for distributed Brillouin optical time-domain analysis sensors that aims to reduce the cost of the sensor by reducing the number of components required for the generation of the two ...
  • Brillouin optical time-domain analysis sensor with pump pulse amplification 

    Mompó Roselló, Juan José; Urricelqui Polvorinos, Javier; Loayssa Lara, Alayn (Optical Society of America, 2016)   Artículo / Artikulua
    We demonstrate a simple technique to provide conventional Brillouin optical time-domain analysis sensors with mitigation for pump pulse attenuation. The technique is based on operating the sensor in loss configuration so ...
  • Gain dependence of the phase-shift spectra measured in coherent Brillouin optical time-domain analysis sensors 

    Mariñelarena Ollacarizqueta, Jon; Urricelqui Polvorinos, Javier; Loayssa Lara, Alayn (IEEE, 2016)   Artículo / Artikulua
    We report on the effects of large pump pulse powers on Brillouin optical time-domain analysis (BOTDA) sensors based on phase-modulated probe wave and coherent self-heterodyne detection. These sensors are particularly ...
  • Experimental demonstration of metamaterials application for mitigating scan blindness in phased array antennas 

    Rodríguez Ulibarri, Pablo; Crépin, Thomas; Martel, Cédric; Boust, Fabrice; Falcone Lanas, Francisco Javier; Loecker, Claudius; Herbertz, Kai; Bertuch, Thomas; Dousset, Thierry; Martinaud, Jean-Paul; Maci, Stefano; Marcotegui Iturmendi, José Antonio; Beruete Díaz, Miguel (EDP Sciences, 2016)   Artículo / Artikulua
    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 ...
  • Chirping techniques to maximize the power-handling capability of harmonic waveguide low-pass filters 

    Teberio Berdún, Fernando; Arregui Padilla, Iván; Gómez Torrent, Adrián; Arnedo Gil, Israel; Chudzik, Magdalena; Zedler, Michael; Goertz, Franz-Josef; Jost, Rolf; Lopetegui Beregaña, José María; Gómez Laso, Miguel Ángel (IEEE, 2016)   Artículo / Artikulua
    A novel chirping technique is applied to the design of very high-power waveguide harmonic low-pass filters. The technique could be used, for instance, to avoid multipactor testing in multicarrier systems such as the ...
  • Zoned fishnet lens antenna with reference phase for side lobe reduction 

    Pacheco Peña, Víctor; Navarro Cía, Miguel; Orazbayev, Bakhtiyar; Minin, Igor V.; Minin, Oleg V.; Beruete Díaz, Miguel (IEEE, 2015)   Artículo / Artikulua
    Reduction of first side lobe level and nulls in artificial fishnet metalenses is accomplished here by applying the reference phase concept along with the zoning technique. Higher focusing efficiency is achieved for a ...
  • ε-near-zero (ENZ) graded index quasi-optical devices: steering and splitting millimeter waves 

    Pacheco Peña, Víctor; Torres Landívar, Víctor; Beruete Díaz, Miguel; Navarro Cía, Miguel; Engheta, Nader (IOP Publishing, 2014)   Artículo / Artikulua
    Graded index ε near-zero (GRIN-ENZ) quasi-optical components such as beam steerers and power splitters are designed, simulated and analyzed. The GRIN-ENZ medium is realized using stacked narrow hollow waveguides whose ...

Más