Now showing items 1-20 of 175

    • 3-D-printed transmit-array antenna for broadband backhaul 5G links at V-band 

      Matos, Sérgio A.; Teixeira, Jorge P.; Costa, Jorge R.; Fernandes, Carlos A.; Río Bocio, Carlos del Upna Orcid (IEEE, 2020)   Artículo / Artikulua  OpenAccess
      The low cost and compactness of transmit-array antennas (TAs) make them attractive for 5G backhaul links. However, the TA advantage is less obvious when considering the broadband operation requirement. Two main factors ...
    • 300 GHz optoelectronic transmitter combining integrated photonics and electronic multipliers for wireless communication 

      Ali, Muhsin; Pérez Escudero, José Manuel Upna Orcid; Guzmán Martínez, Robinson Cruzoe; Lo, Mu Chieh; Ederra Urzainqui, Íñigo Upna Orcid; Gonzalo García, Ramón Upna Orcid; García Muñoz, Luis Enrique (MDPI, 2019)   Artículo / Artikulua  OpenAccess
      THz communications systems at carrier frequencies above 200 GHz are the key to enable next-generation mobile communication networks with 100 Gbit/s wireless data rates. One of the key questions is, which carrier frequency ...
    • 360 nW gate-driven ultra-low voltage CMOS linear transconductor with 1 MHz bandwidth and wide input range 

      Rico-Aniles, Héctor Daniel; Ramírez-Angulo, Jaime; López Martín, Antonio Upna; González Carvajal, Ramón (IEEE, 2020)   Artículo / Artikulua  OpenAccess
      A low voltage linear transconductor is introduced. The circuit is a pseudo differential architecture that operates with ±0.2V supplies and uses 900nA total biasing current. It employs a floating battery technique to achieve ...
    • A 3D ray launching time-frequency channel modeling approach for UWB ranging applications 

      Otim, Timothy; López Iturri, Peio Upna Orcid; Azpilicueta Fernández de las Heras, Leyre Upna Orcid; Bahillo, Alfonso; Falcone Lanas, Francisco Javier Upna Orcid (IEEE, 2020)   Artículo / Artikulua  OpenAccess
      Ultrawideband (UWB) has the ability to achieve decimetre level of ranging accuracy, hence, its wider usage nowadays in the field of positioning. In spite of the attractiveness of UWB, its performance is strongly dependent ...
    • 60 GHz single-layer slot-array antenna fed by groove gap waveguide 

      Ferrando Rocher, Miguel; Valero Nogueira, Alejandro; Herranz Herruzo, José I.; Teniente Vallinas, Jorge Upna Orcid (IEEE, 2019)   Artículo / Artikulua  OpenAccess
      A V-band single-layer low-loss slot-array antenna is presented in this letter. Radiating slots are backed by coaxial cavities, which are fed through a groove gap waveguide E-plane corporate feed network. Cavity resonances ...
    • Advanced graphene-based transparent conductive electrodes for photovoltaic applications 

      Fernández, Susana; Boscá, Alberto; Pedrós, Jorge; Inés Ortigosa, Andrea; Fernández Vallejo, Montserrat Upna; Arnedo Gil, Israel Upna Orcid; González, José Pablo (MDPI, 2019)   Artículo / Artikulua  OpenAccess
      New architectures of transparent conductive electrodes (TCEs) incorporating graphene monolayers in different configurations have been explored with the aim to improve the performance of silicon-heterojunction (SHJ) cell ...
    • Aggregator to electric vehicle LoRaWAN based communication analysis in vehicle-to-grid systems in smart cities 

      Klaina, Hicham; Picallo Guembe, Imanol Upna Orcid; López Iturri, Peio Upna Orcid; Astrain Escola, José Javier Upna Orcid; Azpilicueta Fernández de las Heras, Leyre Upna Orcid; Falcone Lanas, Francisco Javier Upna Orcid (IEEE, 2020)   Artículo / Artikulua  OpenAccess
      Recently, there has been growing attention to the power grid management due to the increasing concerns on global warming. With the advancement in electric vehicles (EV) industry and the evolution in batteries, EVs become ...
    • Aluminum doped zinc oxide (AZO) coated optical fiber LMR refractometers. An experimental demonstration 

      Ozcariz Celaya, Aritz Upna Orcid; Piña-Azamar, Dafne A.; Ruiz Zamarreño, Carlos Upna Orcid; Domínguez Cruz, René; Arregui San Martín, Francisco Javier Upna Orcid (Elsevier, 2019)   Artículo / Artikulua  OpenAccess
      This work presents the experimental demonstration of lossy mode resonance generation by means of aluminum doped zinc oxide thin-films. The use of such material may allow to optimize the performance of LMR-based sensors, ...
    • Antenna mutual coupling suppression over wideband using embedded periphery slot for antenna arrays 

      Alibakhshikenari, Mohammad; Virdee, Bal S.; Shukla, Panchamkumar; See, Chan H.; Abd-Alhameed, Raed; Khalily, Mohsen; Falcone Lanas, Francisco Javier Upna Orcid; Limiti, Ernesto (MDPI, 2018)   Artículo / Artikulua  OpenAccess
      This paper presents a new approach to suppress interference between neighbouring radiating elements resulting from surface wave currents. The proposed technique will enable the realization of low-profile implementation of ...
    • Attention to online channels across the path to purchase: an eye-tracking study 

      Cortiñas Ugalde, Mónica Upna Orcid; Cabeza Laguna, Rafael Upna Orcid; Chocarro Eguaras, Raquel Upna Orcid; Villanueva Larre, Arantxa Upna Orcid (Elsevier, 2019)   Artículo / Artikulua  OpenAccess
      Currently, consumers display what is known as omnichannel behavior: the combined use of digital and physical channels providing them with multiple points of contact with firms. We combine the stimulus-organism-response (S-O-R) ...
    • Bloch waves at the surface of a single-layer coating D-shaped photonic crystal fiber 

      González Valencia, Esteban; Del Villar, Ignacio Upna Orcid; Torres, Pedro (Optical Society of America, 2020)   Artículo / Artikulua  OpenAccess
      Bloch surface wave (BSW) platforms are particularly interesting for light confinement and surface sensitivity, as an alternative to the metal-based surface plasmon polaritons (SPP). However, most of the reported BSW platforms ...
    • Building decentralized fog computing-based smart parking systems: from deterministic propagation modeling to practical deployment 

      Celaya Echarri, Mikel; Froiz Míguez, Iván; Azpilicueta Fernández de las Heras, Leyre Upna Orcid; López Iturri, Peio Upna Orcid; Falcone Lanas, Francisco Javier Upna Orcid (IEEE, 2020)   Artículo / Artikulua  OpenAccess
      The traditional process of finding a vacant parking slot is often inefficient: it increases driving time, traffic congestion, fuel consumption and exhaust emissions. To address such problems, smart parking systems have ...
    • Building standardized and secure mobile health services based on social media 

      Trigo Vilaseca, Jesús Daniel; Rubio, Óscar J.; Martínez de Espronceda Cámara, Miguel; Alesanco, Álvaro; García, José; Serrano Arriezu, Luis Javier (MDPI, 2020)   Artículo / Artikulua  OpenAccess
      Mobile devices and social media have been used to create empowering healthcare services. However, privacy and security concerns remain. Furthermore, the integration of interoperability biomedical standards is a strategic ...
    • Bull’s-eye antenna with circular polarization at millimeter waves based on ridge gap waveguide technology 

      Pérez, Dayan Upna Orcid; Ederra Urzainqui, Íñigo Upna Orcid; Beruete Díaz, Miguel Upna Orcid (IEEE, 2021)   Artículo / Artikulua
      In this communication, a Bull’s-Eye (BE) antenna with circular polarization (CP) based on ridge gap waveguide (RGW) technology is numerically and experimentally demonstrated. The structure is excited from the bottom with ...
    • A Chebyshev transformer-based microstri-to-groove-gap-waveguide inline transition for MMIC packaging 

      Pérez Escudero, José Manuel Upna Orcid; Torres García, Alicia E. Upna Orcid; Gonzalo García, Ramón Upna Orcid; Ederra Urzainqui, Íñigo Upna Orcid (IEEE, 2019)   Artículo / Artikulua  OpenAccess
      The gap waveguide technology has become an alternative to millimeter- and submillimeter-wave electronic circuit packaging thanks to the loss reduction associated with its use. In this paper, a simplified design of an inline ...
    • Cloud tomography applied to sky images: a virtual testbed 

      Mejía, Felipe A.; Kurtz, Ben; Levis, Aviad; Parra Laita, Íñigo de la Upna Orcid; Kleissl, Jan (Elsevier, 2018)   Artículo / Artikulua  OpenAccess
      Two tomographic techniques are applied to two simulated sets of sky images with different cloud fraction. The Algebraic Reconstruction Technique (ART) is applied to optical depth maps from sky images to reconstruct 3-D ...
    • A combination of a vibrational electromagnetic energy harvester and a giant magnetoimpedance (GMI) sensor 

      Beato López, Juan Jesús Upna Orcid; Royo, Isaac Upna Orcid; Algueta-Miguel, Jose M. Upna Orcid; Gómez Polo, Cristina Upna Orcid (MDPI, 2020)   Artículo / Artikulua  OpenAccess
      An energy harvesting device combined with a giant magnetoimpedance (GMI) sensor is presented to analyze low frequency vibrating systems. An electromagnetic harvester based on magnetic levitation is proposed for the electric ...
    • Combined dynamic programming and region-elimination technique algorithm for optimal sizing and management of lithium-ion batteries for photovoltaic plants 

      Berrueta Irigoyen, Alberto Upna Orcid; Heck, Michael; Jantsch, Martin; Ursúa Rubio, Alfredo Upna Orcid; Sanchis Gúrpide, Pablo Upna Orcid (Elsevier, 2018)   Artículo / Artikulua  OpenAccess
      The unpredictable nature of renewable energies is drawing attention to lithium-ion batteries. In order to make full utilization of these batteries, some research works are focused on the management of existing systems, ...
    • Common-mode and phase-to-ground voltage reduction in back-to-back power converters with discontinuous PWM 

      Samanes Pascual, Javier Upna Orcid; Gubía Villabona, Eugenio Upna Orcid; Juankorena Saldias, Xabier Upna; Gironés Remírez, Carlos Upna (IEEE, 2020)   Artículo / Artikulua  OpenAccess
      Discontinuous space vector pulsewidth modulation (DSVPWM) techniques are an interesting option for three-phase, two-level power converters when efficiency is a key factor. Such is the case of back-to-back (B2B) power ...
    • A compact wide bandpass filter for satellite communications with improved out-of-band rejection 

      Ahmed, Badiaa Ait; Naghar, Azzeddin; Aghzout, Otman; Vazquez Alejos, Ana; Falcone Lanas, Francisco Javier Upna Orcid (AEM, 2020)   Artículo / Artikulua  OpenAccess
      This paper presents a compact C-band bandpass filter with improved out-of-band rejection. It consists of a symmetric three-pole parallel coupled line microstrip loaded with complementary split ring resonators (CSRRs) and ...