• AC amplifiers with ultra-low corner frequency by using bootstrapping 

      Martincorena Arraiza, Maite Upna Orcid; Carlosena García, Alfonso Upna Orcid; Cruz Blas, Carlos Aristóteles de la Upna Orcid; 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 ...
    • Analysis and synthesis of vibrato in lyric singers 

      Arroabarren Alemán, Ixone Upna; Carlosena García, Alfonso Upna Orcid (2002)   Contribución a congreso / Biltzarrerako ekarpena  OpenAccess
      In this paper two aspects of the vibrato signal characterisation are presented. First, an analysis method, which breaks down the musical signal into its different partials, and decomposes them into two separate ...
    • Computation of greatest common divisor for the blind deconvolution of transient impulsive signals 

      Lecumberri Villamediana, Pablo Upna; Gómez Fernández, Marisol Upna Orcid; Carlosena García, Alfonso Upna Orcid (Universitat Politècnica de Catalunya, 2005)   Contribución a congreso / Biltzarrerako ekarpena  OpenAccess
      We propose a new blind deconvolution method for transient impulsive signals in a single input – multiple output (SIMO) system. The method exploits the data redundancy inherent to SIMO multichannel systems to obtain an ...
    • Design of low-cost smart accelerometers 

      Carlosena García, Alfonso Upna Orcid; López Martín, Antonio Upna Orcid; Massarotto, Marco Upna; Cruz Blas, Carlos Aristóteles de la Upna Orcid; Lecumberri Villamediana, Pablo Upna; Gómez Fernández, Marisol Upna Orcid; Pintor Borobia, Jesús María Upna Orcid; Gárriz Sanz, Sergio Upna (Universitat Politècnica de Catalunya, 2005)   Contribución a congreso / Biltzarrerako ekarpena  OpenAccess
      The goal of this project is to design a low-cost smart accelerometer, making use of a piezoelectric element as basic sensing material, and adding a mixed-mode conditioning circuit.
    • Design of MOS-translinear multiplier/dividers in analog VLSI 

      López Martín, Antonio Upna Orcid; Carlosena García, Alfonso Upna Orcid (Hindawi Publishing Corporation, 2000)   Artículo / Artikulua  OpenAccess
      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 ...
    • Diseño y aplicaciones de un elemento activo universal 

      Cabeza Laguna, Rafael Upna Orcid (Universidad Pública de Navarra / Nafarroako Unibertsitate Publikoa, 1996)   Tesis doctoral / Doktoretza tesia  OpenAccess
      La lista de elementos activos presentes en el comienzo de la década de los noventa es numerosa y no exenta de repeticiones o conceptos poco útiles. Por otra parte no se presenta en la literatura ningún esfuerzo a la hora ...
    • Effect of the glottal source and the vocal tract on the partials amplitude of vibrato in male voices 

      Arroabarren Alemán, Ixone Upna; Carlosena García, Alfonso Upna Orcid (Acoustical Society of America, 2006)   Artículo / Artikulua  OpenAccess
      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 ...
    • A family of alternating current amplifiers for ultra-low frequency operation 

      Martincorena Arraiza, Maite Upna Orcid; Carlosena García, Alfonso Upna Orcid; Cruz Blas, Carlos Aristóteles de la Upna Orcid; Beloso Legarra, Javier Upna Orcid; López Martín, Antonio Upna Orcid (Wiley, 2021)   Artículo / Artikulua  OpenAccess
      A family of capacitively coupled alternating current (AC) amplifiers featuring ultra-low (below 1 Hz) corner frequency is presented. This is achieved by using high-gain devices which actively boost feedback resistance and ...
    • Glottal spectrum based inverse filtering 

      Arroabarren Alemán, Ixone Upna; Carlosena García, Alfonso Upna Orcid (ISCA, 2003)   Contribución a congreso / Biltzarrerako ekarpena  OpenAccess
      In this paper a new inverse filtering technique for the time-domain estimation of the glottal excitation is presented. This approach uses the DAP modeling for the vocal tract characterization, and a spectral model for the ...
    • High-order PLL design with constant phase margin 

      Ugarte Gil, Mikel Upna; Carlosena García, Alfonso Upna Orcid (IEEE, 2010)   Contribución a congreso / Biltzarrerako ekarpena  OpenAccess
      In this paper we describe a novel procedure to design high-type high-order Phase Locked Loops (PLLs) from lower order prototypes, preserving a prescribed Phase Margin (PM). The method builds on a model recently proposed ...
    • Instantaneous amplitude and phase signal modeling for harmonic removal in wind turbines 

      Zivanovic, Miroslav Upna Orcid; Plaza Puértolas, Aitor Upna Orcid; Iriarte Goñi, Xabier Upna Orcid; Carlosena García, Alfonso Upna Orcid (Elsevier, 2023)   Artículo / Artikulua  OpenAccess
      We present a novel approach to harmonic disturbance removal in single-channel wind turbine acceleration data by means of time-variant signal modeling. Harmonics are conceived as a set of quasi-stationary sinusoids whose ...
    • Micropower class AB low-pass analog filter based on the super-source follower 

      Martincorena Arraiza, Maite Upna Orcid; Cruz Blas, Carlos Aristóteles de la Upna Orcid; López Martín, Antonio Upna Orcid; Carlosena García, Alfonso Upna Orcid (IEEE, 2022)   Artículo / Artikulua  OpenAccess
      An improved class AB version of the super source follower is used to implement a compact and power-efficient second order analog low-pass filter. The proposed circuit achieves a 41% power reduction as well as an improvement ...
    • Modelling of vibrato production 

      Arroabarren Alemán, Ixone Upna; Carlosena García, Alfonso Upna Orcid (2004)   Contribución a congreso / Biltzarrerako ekarpena  OpenAccess
      In this paper, a novel Non-Interactive Source-Filter model for singing voice, incorporating vibrato, is proposed. In this way the periodic frequency variation, peculiar to vibrato is included in a simplified signal model ...
    • Multichannel blind deconvolution of impulsive signals 

      Lecumberri Villamediana, Pablo Upna; Gómez Fernández, Marisol Upna Orcid; Carlosena García, Alfonso Upna Orcid (2005)   Contribución a congreso / Biltzarrerako ekarpena  OpenAccess
      In this communication, the problem of blind deconvolution of transient, impulsive signals in a multichannel environment is addressed. This kind of signals arise naturally, or are used as external excitation, in many ...
    • A novel design method for phase-locked loops of any order and type 

      Carlosena García, Alfonso Upna Orcid; Mànuel Lázaro, Antonio (IEEE, 2006)   Contribución a congreso / Biltzarrerako ekarpena  OpenAccess
      In this paper a novel approach to the design of PLLs is presented, which can be used regardless of their Order and Type. The method stems from the fact that high-frequency poles in the loop filter determine filtering ...
    • A novel PLL architecture 

      Osa, Juan I.; Carlosena García, Alfonso Upna Orcid; López Martín, Antonio Upna Orcid (2000)   Contribución a congreso / Biltzarrerako ekarpena  OpenAccess
      A novel phase-locked loop scheme is proposed in this paper, whose main distinguishing features are infinite hold-in range, pull-out range fractionally constant and also a ripple fractionally constant. To this end, it ...
    • Performance comparison and design guidelines for Type II and Type III PLLs 

      Ugarte Gil, Mikel Upna; Carlosena García, Alfonso Upna Orcid (Birkhauser, 2015)   Artículo / Artikulua  OpenAccess
      The advantages provided by Type III PLLs are poorly known, since these devices are very often considered unstable and difficult, or even impossible, to design. In this paper, a performance comparison between Type II and ...
    • Presentación e inauguración de la Jornada 

      Carlosena García, Alfonso Upna Orcid; López López, Hugo Upna Orcid (2016)   Contribución a congreso / Biltzarrerako ekarpena  OpenAccess
      El objetivo de la Jornada es dar a conocer las posibilidades de participación en acciones ERASMUS+ diferentes a la movilidad, entre otras: titulaciones de máster conjuntas Erasmus Mundus, asociaciones estratégicas en el ...
    • Seinaleak eta espektroak: naturaren zikloen bila 

      Carlosena García, Alfonso Upna Orcid (Universidad Pública de Navarra / Nafarroako Unibertsitate Publiko, 2023)   Otros / Bestelakoak  OpenAccess

      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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