Now showing items 1-20 of 262

    • ±0.25 V Class-AB CMOS capacitance multiplier and precision rectifiers 

      Pourashraf, Shirin; Ramírez-Angulo, Jaime; Hinojo Montero, José María; González Carvajal, Ramón; López Martín, Antonio Upna Orcid (IEEE, 2019)   Artículo / Artikulua  OpenAccess
      Reduction of minimum supply requirements is a crucial aspect to decrease the power consumption in VLSI systems. A high performance capacitance multiplier able to operate with supplies as low as ±0.25 V is presented. It is ...
    • 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 Orcid; 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 Upna; 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 ...
    • AC amplifiers with ultra-low corner frequency by using bootstrapping 

      Martincorena Arraiza, Maite Upna Orcid; Carlosena García, Alfonso Upna Orcid; De la Cruz Blas, Carlos A.; López Martín, Antonio Upna Orcid (Institution of Engineering and Technology, 2021)   Artículo / Artikulua  OpenAccess
      A novel architecture for an AC (i.e. high-pass) amplifier is proposed allowing a drastic reduction of the cutoff frequency to the sub-Hertz range. It builds upon the classic AC configuration with a high gain amplifier and ...
    • AC coupled amplifier with a resistance multiplier technique for ultra-low frequency operation 

      Martincorena Arraiza, Maite Upna Orcid; Cruz Blas, Carlos Aristóteles de la Upna Orcid; Carlosena García, Alfonso Upna Orcid; López Martín, Antonio Upna Orcid (Elsevier, 2022)   Artículo / Artikulua  OpenAccess
      This paper proposes a novel, tunable AC coupled capacitive feedback amplifier, exhibiting an ultra-low high pass corner frequency. This is accomplished by actively boosting the output resistive value of a MOS transistor ...
    • Accurate pupil center detection in off-the-shelf eye tracking systems using convolutional neural networks 

      Larumbe Bergera, Andoni Upna Orcid; Garde Lecumberri, Gonzalo Upna; Porta Cuéllar, Sonia Upna Orcid; Cabeza Laguna, Rafael Upna Orcid; Villanueva Larre, Arantxa Upna Orcid (MDPI, 2021)   Artículo / Artikulua  OpenAccess
      Remote eye tracking technology has suffered an increasing growth in recent years due to its applicability in many research areas. In this paper, a video-oculography method based on convolutional neural networks (CNNs) for ...
    • 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 ...
    • Advances in fiber optic DNA-based sensors: a review 

      Santano, Desiree Upna Orcid; Urrutia Azcona, Aitor Upna Orcid; Ruiz Zamarreño, Carlos Upna Orcid; Del Villar, Ignacio Upna Orcid (IEEE, 2021)   Artículo / Artikulua  OpenAccess
      DNA is becoming increasingly important in the domain of optical fiber sensors, either as a tool for biosensing, or as a target to detect. In this review the main contributions of the last years are presented both in the ...
    • Aggregator to electric vehicle LoRaWAN based communication analysis in vehicle-to-grid systems in smart cities 

      Klaina, Hicham Upna; 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, ...
    • Analysis of low power wide area network wireless technologies in smart agriculture for large-scale farm monitoring and tractor communications 

      Klaina, Hicham; Picallo Guembe, Imanol Upna Orcid; López Iturri, Peio Upna Orcid; Campo-Bescós, Miguel Upna Orcid; Azpilicueta Fernández de las Heras, Leyre Upna Orcid; Aghzout, Otman; Vázquez Alejos, Ana; Falcone Lanas, Francisco Javier Upna Orcid (Elsevier, 2022)   Artículo / Artikulua  OpenAccess
      In this paper, the assessment of multiple scenario cases for large-scale farm monitoring using Low-Power Wide-Area Network (LPWAN) based near-ground sensor nodes with the interaction of both tractors and farmers are ...
    • Analysis of the combinatory effect of uniaxial electrical and magnetic anisotropy on the input impedance and mutual coupling of a printed dipole antenna 

      Bouknia, Mohamed Lamine; Zebiri, Chemseddine; Sayad, Djamel; Elfergani, Issa; Alibakhshikenari, Mohammad; Rodriguez, Jonathan; Abd-Alhameed, Raed; Falcone Lanas, Francisco Javier Upna Orcid; Limiti, Ernesto (IEEE, 2021)   Artículo / Artikulua  OpenAccess
      The main objective of this work is to investigate the combinatory effects of both uniaxial magnetic and electrical anisotropies on the input impedance, resonant length and the mutual coupling between two dipoles printed ...
    • 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 ...
    • Antenna on chip (AoC) design using metasurface and SIW technologies for THz wireless applications 

      Althuwayb, Ayman Abdulhadi; Alibakhshikenari, Mohammad; Virdee, Bal S.; Benetatos, Harry; Falcone Lanas, Francisco Javier Upna Orcid; Limiti, Ernesto (MDPI, 2021)   Artículo / Artikulua  OpenAccess
      This paper presents the design of a high-performance 0.45-0.50 THz antenna on chip (AoC) for fabrication on a 100-micron GaAs substrate. The antenna is based on metasurface and substrate-integrated waveguide (SIW) technologies. ...
    • 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) ...
    • Basketball Player On-Body Biophysical and Environmental Parameter Monitoring Based on Wireless Sensor Network Integration 

      Picallo Guembe, Imanol Upna Orcid; López iturri, Peio Upna Orcid; Astrain Escola, José Javier Upna Orcid; Aguirre Gallego, Erik Upna Orcid; Azpilicueta Fernández de las Heras, Leyre; Celaya-Echarri, Mikel; Villadangos Alonso, Jesús Upna Orcid; Falcone Lanas, Francisco Upna Orcid (IEEE, 2021)   Artículo / Artikulua  OpenAccess
      Sport activities have benefited in recent years from the progressive adoption of different technological assets in order to improve individual as well as group training, collect different statistics or enhance the spectator ...
    • Beyond near-infrared lossy mode resonances with fluoride glass optical fiber 

      Vitoria Pascual, Ignacio Upna Orcid; Ruiz Zamarreño, Carlos Upna Orcid; Ozcariz Celaya, Aritz Upna Orcid; Imas González, José Javier Upna Orcid; Matías Maestro, Ignacio Upna Orcid (Optica, 2021)   Artículo / Artikulua  OpenAccess
      The objective of this Letter consists of the exploration of the lossy mode resonance (LMR) phenomenon beyond the nearinfrared region and specifically in the short wave infrared region (SWIR) and medium wave infrared region ...