Now showing items 1-20 of 23

  • A low-power-consumption out-of-Plane electrothermal actuator 

    Girbau Sala, David; Llamas Morote, Marco Antonio; Casals Terré, Jasmina; Simó Selvas, Francisco Javier; Pradell i Cara, Lluís; Lázaro Guillén, Antoni (IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC, 2007-06-30)
    Article
    Open Access
    This paper proposes a new vertical electrothermal actuator. It can be considered as a hybrid between the traditional in-plane buckle-beam actuator and the vertical hot-cold actuator. It is here referred to as vertical ...
  • A method for characterizing coplanar waveguide-to-microstrip transitions, and its application to the measurement of microstrip devices with coplanar microprobes 

    Maya Sánchez, Mª del Carmen; Lázaro Guillén, Antoni; Pradell i Cara, Lluís; Paco, D. de (JOHN WILEY & SONS INC, 2003-12-31)
    Article
    Open Access
    This paper presents a method for characterizing coplanar waveguide-to-microstrip (CPW-M) transitions by using on-wafer coplanar (CPW) microprobes. It is based on extracting the transmission matrix of the CPW-M transition ...
  • A Method for the Determination of a Distributed FET Noise-Model Based on Matched-Source Noise-Figure Measurements 

    Maya Sánchez, Mª del Carmen; Pradell i Cara, Lluís; Lázaro Guillén, Antoni (JOHN WILEY & SONS INC, 2004-05-31)
    Article
    Open Access
    A new method for the determination of a distributed FET noise model is presented. It is based on the extraction of the intrinsic noise-correlation matrix of an elemental section of the device from the device's noise figure, ...
  • A Method to Simultaneously Extract the Small-Signal Equivalent Circuit and Noise Parameters of Heterojunction Bipolar Transistors 

    Maya Sánchez, Mª del Carmen; Lázaro Guillén, Antoni; Pradell i Cara, Lluís (JOHN WILEY & SONS INC, 2006-07-31)
    Article
    Open Access
    A method to extract the elements of the small-signal equivalent circuit and the noise parameters (NPs) of heterojunction bipolar transistors (HBTs) is presented. The extraction is done by simultaneous fitting of the measured ...
  • A wideband detector for the 30 Ghz channel of the Planck mission low frequency instrument 

    Paco Sánchez, Pedro Antonio de; Lázaro Guillén, Antoni; Pradell i Cara, Lluís (GORDON BREACH SCI PUBL LTD, 2000-05-31)
    Article
    Open Access
    Design considerations of a 30 GHz detector prototype for the Planck Low Frequency Instrument (LFI) are presented. A simple detector configuration based on a commercial Schottky diode is used, featuring a good linearity and ...
  • Application of CAD load-pull techniques in mixer design 

    Velázquez, A.; Lázaro Guillén, Antoni; Pradell i Cara, Lluís; Comerón Tejero, Adolfo (2003-02)
    Article
    Open Access
    This work describes the application of a commercial CAD software to implement load-pull techniques in the design of microwave mixers. This method is used to generate conversion-loss regions when a diode is pumped and ...
  • Application of CAD load_pull techniques in mixer design 

    Velázquez, A.; Lázaro Guillén, Antoni; Pradell i Cara, Lluís; Comerón Tejero, Adolfo (JOHN WILEY & SONS INC, 2003-02-28)
    Article
    Open Access
    This work describes the application of a commercial CAD software to implement load-pull techniques in the design of microwave mixers. This method is used to generate conversion-loss regions when a diode is pumped and ...
  • Bias-dependence of FET intrinsic noise sources, determined with a quasi-2D model 

    Lázaro Guillén, Antoni; Maya Sánchez, Mª del Carmen; Pradell i Cara, Lluís (JOHN WILEY & SONS INC, 2003-11-30)
    Article
    Open Access
    The bias-dependence of microwave-FET intrinsic noise sources in their hybrid configuration is theoretically determined, using a new quasi-2D (Q-2D) physical model based on Thornber's current equation [8]. It is shown that ...
  • Characterization of dynamics and power handling of RF MEMS using vector measurement techniques 

    Girbau Sala, David; Lázaro Guillén, Antoni; Pradell i Cara, Lluís (IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC, 2004-11-30)
    Article
    Open Access
    This paper proposes a new method to measure dynamics and power handling of RF microelectromechanical systems (MEMS) devices based on a mobile membrane. The method uses in-phase/quadrature demodulation of an RF signal ...
  • Characterization of dynamics in RF-MEMS switches 

    Llamas Morote, Marco Antonio; Girbau Sala, David; Pradell i Cara, Lluís; Lázaro Guillén, Antoni; Giacomozzi, Flavio; Colpo, S (2009)
    Conference report
    Open Access
    This paper proposes a new method to measure dynamics and power handling of RF microelectromechanical systems (MEMS) devices based on a mobile membrane. The method uses in-phase/quadrature demodulation of an RF signal ...
  • Direct extraction of all four transistor noise parameters from 50 noise figure measurements 

    Lázaro Guillén, Antoni; Pradell i Cara, Lluís; Beltrán, A.; O'Callaghan Castellà, Juan Manuel (IEE, 1998-02-05)
    Article
    Open Access
    A new method for measuring the four noise parameters (NPs) of a transistor is presented. It is based on the determination of its intrinsic noise matrix elements (C11INT, C22INT, Re(C12INT), Im(C12INT)) by fitting the ...
  • Distortion produced by RF MEMS varactors on digital communication signals 

    Lázaro Guillén, Antoni; Girbau Sala, David; Pradell i Cara, Lluís (JOHN WILEY & SONS INC, 2006-02-28)
    Article
    Open Access
    This paper presents a study of the nonlinear effects introduced by MEMS varactors when excited with digitally modulated RF signals (QPSK and 16 QAM). The study is based on simulating a nonlinear model of the MEMS device ...
  • Electrothermally actuated RF MEMS switches suspended on a low-resistivity substrate 

    Girbau Sala, David; Pradell i Cara, Lluís; Lázaro Guillén, Antoni; Nebot Serra, Àlvar (IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC, 2007-10-31)
    Article
    Open Access
    This paper presents an electrothermally actuated lateral resistive-contact switch for application to low-gigahertz-band communication systems. It was manufactured on a standard low-resistivity substrate, and its RF performance ...
  • Extraction of an avalanche diode noise model for its application as on-wafer noise source 

    Maya Sánchez, Mª del Carmen; Lázaro Guillén, Antoni; Pradell i Cara, Lluís (JOHN WILEY & SONS INC, 2003-07-31)
    Article
    Open Access
    This paper presents a method to characterize the excess noise ratio (ENR) of an unmatched avalanche noise diode for application as an on-wafer noise source. It is based on the determination of a broadband device noise ...
  • Extraction of noise parameters of transistor using a spectrum analyser and 50^ noise figure measurements only. 

    Lázaro Guillén, Antoni; Pradell i Cara, Lluís (IEE, 1998-11-26)
    Article
    Open Access
    A method for measuring the four noise parameters of a transistor in the microwave range using a configuration based on a conventional spectrum analyser is presented. In contrast to previous methods, it requires wideband ...
  • Fet noise-parameter determination using a novel technique based on 50 noise measurements 

    Lázaro Guillén, Antoni; Pradell i Cara, Lluís; O'Callaghan Castellà, Juan Manuel (IEEE, 1999)
    Article
    Open Access
    A novel method for measuring the four noise parameters of a field-effect transistor (FET) is presented. It is based on the determination of its intrinsic noise matrix elements [C11INT, C22INT, Re(C12 INT), Im(C12INT)] by ...
  • Measurement of on-wafer transistor noise parameters without a tuner using unrestricted noise sources 

    Lázaro Guillén, Antoni; Maya Sánchez, Mª del Carmen; Pradell i Cara, Lluís (HORIZON HOUSE PUBLICATIONS INC, 2002-03-31)
    Article
    Open Access
    The authors present a method for calibrating the four noise parameters of a noise receiver which does not require a tuner The method permits using general (mismatched) noise sources, which may present very different source ...
  • Method for measuring noise parameters of microwave two-port 

    Lázaro Guillén, Antoni; Pradell i Cara, Lluís; O'Callaghan Castellà, Juan Manuel (IEE, 1998-06-30)
    Article
    Open Access
    A new tuner-based method for measuring the four noise-parameters of a two-port is proposed. It makes use of a novel measurement ratio that includes noise powers and mismatch factors simultaneously. In contrast to previous ...
  • Noise model of a reverse-biased Cold-FET applied to the characterization of its ENR 

    Maya Sánchez, Mª del Carmen; Lázaro Guillén, Antoni; Pradell i Cara, Lluís (JOHN WILEY & SONS INC, 2004-02-28)
    Article
    Open Access
    This paper presents a broadband-noise circuit model for a cold-FET (Vds = 0 V) with a reverse-biased gate. The noise model includes two intrinsic uncorrelated noise-current sources whose spectral densities are determined ...
  • Nonlinear actuation model for lateral electrostatically-actuated DC-contact RF MEMS series switches. 

    Lázaro Guillén, Antoni; Girbau Sala, David; Pradell i Cara, Lluís; Nebot Serra, Àlvar (JOHN WILEY & SONS INC, 2007-06-01)
    Article
    Open Access
    In this work, a nonlinear model to predict actuation characteristics in lateral electrostatically-actuated DC-contact MEMS switches is proposed. In this case a parallel-plate approximation cannot be applied. The model ...