• Validation of 3D simulation tool for radio channel modeling at 60 GHz: a meeting point for empirical and simulation-based models 

      Celaya Echarri, Mikel Upna Orcid; Azpilicueta Fernández de las Heras, Leyre Upna Orcid; López Iturri, Peio Upna Orcid; Falcone Lanas, Francisco Javier Upna Orcid; García Sánchez, Manuel; Vázquez Alejos, Ana (Elsevier, 2020)   Artículo / Artikulua  OpenAccess
      The radio channel modelling of the millimeter wave bands for the fifth generation of wireless mobile communications, appears as a challenge for both empirical and simulation approaches. In this paper we discuss the use of ...
    • Validation of HTTP response time from network traffic as an alternative to web browser instrumentation 

      López Romera, Carlos Upna; Morató Osés, Daniel Upna Orcid; Magaña Lizarrondo, Eduardo Upna Orcid; Izal Azcárate, Mikel Upna Orcid (IEEE, 2021)   Artículo / Artikulua  OpenAccess
      The measurement of response time in hypertext transfer protocol (HTTP) requests is the most basic proxy measurement method for evaluating web browsing quality. It is used in the research literature and in application ...
    • Validation of the filling factor index to study the filling process of the sEMG signal in the quadriceps 

      Rodríguez Falces, Javier Upna Orcid; Malanda Trigueros, Armando; Mariscal, Cristina; Niazi, Imran Khan; Navallas Irujo, Javier (Elsevier, 2023)   Artículo / Artikulua  OpenAccess
      Introduction: The EMG filling factor is an index to quantify the degree to which an EMG signal has been filled. Here, we tested the validity of such index to analyse the EMG filling process as contraction force was ...
    • Valorization of insulation cellulose waste as solid biomass fuel 

      Espuelas Zuazu, Sandra Upna Orcid; Marcelino Sádaba, Sara Upna Orcid; Castillo, Jesús María del Upna Orcid; García, Beñat; Seco Meneses, Andrés Upna Orcid (MDPI, 2021)   Artículo / Artikulua  OpenAccess
      This paper investigates the ability of insulation cellulose fiber powder (CFP) to be pelletized for its valorization as biomass fuel. CFP is a waste originating from insulation cellulose manufacturing that lacks any method ...
    • Vertically coupled InP/InGaAsP microring lasers using a single epitaxial growth and singleside lithography 

      García López, Óscar; Thourhout, Dries Van; Verstuyft, Steven; López-Amo Sáinz, Manuel Upna Orcid; Baets, Roel; Galarza Galarza, Marko Upna Orcid (IEEE, 2020)   Artículo / Artikulua  OpenAccess
      The experimental demonstration of vertical microring lasers requiring only one single epitaxial growth and two single-side lithographic steps is presented, in what is the simplest fabrication scheme for such devices published ...
    • Very-low frequency capacitively coupled AC amplifier with a current feedback operational amplifier 

      Beloso Legarra, Javier Upna Orcid; Cruz Blas, Carlos Aristóteles de la Upna Orcid; Carlosena García, Alfonso Upna Orcid; Martincorena Arraiza, Maite Upna Orcid (Wiley, 2023)   Artículo / Artikulua  OpenAccess
      In this paper, we propose the idea of using transimpedance amplifiers, in lieu of operational amplifiers (OAs) or transconductance amplifiers (OTAs) to design capacitively coupled AC amplifiers. The idea is demonstrated ...
    • Virtual antenna array for reduced energy per bit transmission at Sub-5 GHz mobile wireless communication systems 

      Alibakhshikenari, Mohammad; Virdee, Bal S.; Mariyanayagam, Dion; García Zuazola, Ignacio Julio; Benetatos, Harry; Althuwayb, Ayman Abdulhadi; Alali, Bader; Xu, Kai-Da; Falcone Lanas, Francisco Javier Upna Orcid (Elsevier, 2023)   Artículo / Artikulua  OpenAccess
      This paper presents an innovative technique to synthesize a virtual antenna array (VAA) that consumes less energy than conventional antenna arrays that are used in mobile communications systems. We have shown that for a ...
    • Virtual FBGs using saturable absorbers for sensing with fiber lasers 

      Rodríguez Cobo, Luis; Pérez Herrera, Rosa Ana Upna Orcid; Quintela, M. A.; Ruiz Lombera, Rubén; López-Amo Sáinz, Manuel Upna Orcid; López Higuera, José Miguel (MDPI, 2018)   Artículo / Artikulua  OpenAccess
      The spectral narrowing of Fiber Bragg Gratings (FBGs) introduced by unpumped Er-doped fiber (EDF) was analyzed for fiber lasers (FL). Owing to spatial hole burning (SHB), the spectral response of a virtual FBG can be ...
    • A water content continuous monitoring of grapevine xylem tissue using a portable low-power cost-effective FMCW radar 

      Quemada Mayoral, Carlos Upna Orcid; García González, Cebrián Upna; Iriarte Galarregui, Juan Carlos Upna Orcid; Marín Ederra, Diana Upna Orcid; Gastón Beraza, Diego; Miranda Jiménez, Carlos Upna Orcid; Gonzalo García, Ramón Upna Orcid; Maestrojuán Biurrun, Itziar Upna; Santesteban García, Gonzaga Upna Orcid; Ederra Urzainqui, Íñigo Upna Orcid (IEEE, 2019)   Artículo / Artikulua  OpenAccess
      This paper presents the real-time monitoring of a grapevine’s water content that flows up through the xylem tissue by means of a frequency-modulated continuous-wave (FMCW) radar. The application of an optimization process, ...
    • Watt-level green random laser at 532  nm by SHG of Yb-doped fiber laser 

      Rota Rodrigo, Sergio Upna; Gouhier, B.; Dixneuf, C.; Antoni Micollier, L.; Guiraud, G.; Leandro González, Daniel Upna Orcid; López-Amo Sáinz, Manuel Upna Orcid; Traynor, N.; Santarelli, Giorgio (Optical Society of America, 2018)   Artículo / Artikulua  OpenAccess
      We have developed a Watt-level random laser at 532 nm. The laser is based on a 1064 nm random distributed ytterbium-gain assisted fiber laser seed with a 0.35 nm line-width and 900 mW polarized output power. A study for ...
    • Wavelength and intensity based lossy mode resonance breathing sensor 

      Bohórquez Navarro, Dina Luz Upna Orcid; Del Villar, Ignacio Upna Orcid; Corres Sanz, Jesús María Upna Orcid; Matías Maestro, Ignacio Upna Orcid (Elsevier, 2021)   Artículo / Artikulua  OpenAccess
      Copper oxide (CuO) allows the generation of lossy mode resonance (LMR) in a wide wavelength range of the optical spectrum, both in the visible and the near-infrared (NIR). For this, it is necessary to use a configuration ...
    • Wavelength converter using a highly Er-doped optical fiber ring laser 

      Pérez Herrera, Rosa Ana Upna Orcid; López-Amo Sáinz, Manuel Upna Orcid; Rodríguez, Luis; Ventura Rípodas, Daniel; López Higuera, José Miguel (IOP Publishing, 2018)   Artículo / Artikulua  OpenAccess
      This work presents an all-fiber wavelength converter based on a highly Er-doped fiber laser, which has been experimentally demonstrated. Frequencies from several kilohertz up to tens of gigahertz have been investigated. ...
    • Wavelength-switchable L-band fiber laser assisted by random reflectors 

      Pérez Herrera, Rosa Ana Upna Orcid; Roldán Varona, Pablo; Sánchez-González, Arturo; Rodríguez Cobo, Luis; López Higuera, José Miguel; López-Amo Sáinz, Manuel Upna Orcid (EDP Open, 2023)   Artículo / Artikulua  OpenAccess
      A wavelength-switchable L-band erbium-doped fiber laser (EDFL) assisted by an artificially controlled backscattering (ACB) fiber reflector is here presented. This random reflector was inscribed by femtosecond (fs) laser ...
    • Winding resistance measurement in power inductors - understanding the impact of the winding mutual resistance 

      Barrios Rípodas, Ernesto Upna Orcid; Elizondo Martínez, David Upna Orcid; Ursúa Rubio, Alfredo Upna Orcid; Sanchis Gúrpide, Pablo Upna Orcid (IEEE, 2021)   Artículo / Artikulua  OpenAccess
      Inductors are cornerstone components in power electronics converters. Since winding loss is the dominant loss mechanism in these components, its accurate measurement is fundamental for the validation of the inductor's ...
    • Wireless characterization and assessment of an UWB-Based system in industrial environments 

      Picallo Guembe, Imanol Upna Orcid; López Iturri, Peio Upna Orcid; Klaina, Hicham Upna; Glaría Ezker, Guillermo; Sáez de Jaúregui Urdanoz, Félix; Zabalza Cestau, José Luis; Azpilicueta Fernández de las Heras, Leyre Upna Orcid; Falcone Lanas, Francisco Javier Upna Orcid (IEEE, 2021)   Artículo / Artikulua  OpenAccess
      The advent of Indsutrial Internet of Things is one of the main drivers for the implementation of Industry 4.0 scenarios and applications, in which wireless communication systems play a key role in terms of flexibility, ...
    • Zero-loss switching in LLC resonant converters under discontinuous conduction mode: analysis and design methodology 

      Elizondo Martínez, David Upna Orcid; Barrios Rípodas, Ernesto Upna Orcid; Larequi, Íñigo; Ursúa Rubio, Alfredo Upna Orcid; Sanchis Gúrpide, Pablo Upna Orcid (IEEE, 2023)   Artículo / Artikulua  OpenAccess
      Many thriving applications where isolation is required, such as LED drivers, traction and EV fast charging, implement LLC resonant converters, particularly when voltage regulation is not required or an additional ...

      El Repositorio ha recibido la ayuda de la Fundación Española para la Ciencia y la Tecnología para la realización de actividades en el ámbito del fomento de la investigación científica de excelencia, en la Línea 2. Repositorios institucionales (convocatoria 2020-2021).
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