Exploració per tema "equivalent circuits"

Ara es mostren els items 1-13 de 13

    • 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
      Accés obert
      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 ...

    • 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
      Accés obert
      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
      Accés obert
      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 ...

    • Circuit model for a coplanar-slotline cross 

      Ribó i Pal, Miquel; Pradell i Cara, Lluís (IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC, 2000-12-31)
      Article
      Accés obert
      A new 6-port “circuit-model” for coplanar-slotline crosses is presented. The model is based on the separation of the two fundamental Coplanar Waveguide (CPW) modes (even and odd) into different ports. It generalizes previous ...

    • Circuit Model for mode conversion in coplanar waveguide assymmetric shunt impedances 

      Ribó i Pal, Miquel; Pradell i Cara, Lluís (IEE-INST ELEC ENG, 1999-04-30)
      Article
      Accés obert
      A new `circuit model' for the conversion between even and odd modes in coplanar waveguide asymmetric shunt impedances is presented. The model is based on the separation of modes into two input and two output ports. In ...

    • Circuit model for mode conversion in coplanar waveguide asymmetric series-impedances 

      Ribó i Pal, Miquel; Cruz Llopis, Luis Javier de la; Pradell i Cara, Lluís (IEE-INST ELEC ENG, 1999-10-31)
      Article
      Accés obert
      A new `circuit model' for converting between even and odd modes in asymmetric series impedances in the ground plane of a coplanar waveguide is presented. The model is based on the separation of modes into two input and two ...

    • 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
      Accés obert
      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 ...

    • 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
      Accés obert
      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 ...

    • Model predicts large-signal modfet performance 

      O'Callaghan Castellà, Juan Manuel; Beyer, J. B. (PENTON MEDIA, INC, 1989-11-30)
      Article
      Accés obert
      Modulation doped FETs (MODFETs) provide low-noise performance in many medium- and high-power microwave applications. Unfortunately, there are few large-signal models available for MODFETs, and determining the parameters ...

    • 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
      Accés obert
      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 Distortion in a 8-Pole Quasi-Elliptic Bandpass HTS Filter for CDMA System 

      Collado Gómez, Juan Carlos; Mateu Mateu, Jordi; Menéndez Nadal, Óscar; O'Callaghan Castellà, Juan Manuel (IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC, 2005-06-30)
      Article
      Accés obert
      High Temperature Superconductor materials are known to produce intermodulation and other nonlinear effects which may restrict their use in wireless communication systems. Quantifying this degradation is crucial in determining ...

    • Nonlinear Model of Coupled Superconducting Lines 

      Mateu Mateu, Jordi; Collado Gómez, Juan Carlos; O'Callaghan Castellà, Juan Manuel (IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC, 2005-06-30)
      Article
      Accés obert
      High Temperature Superconductor materials are known to produce intermodulation and other nonlinear effects. In planar structures, these nonlinearities depend on the field configuration on the strip, which in turn strongly ...

    • Nonlinear performance characterization in an eight-pole quasi-elliptic bandpass filter 

      Mateu Mateu, Jordi; Collado Gómez, Juan Carlos; Menéndez Nadal, Óscar; O'Callaghan Castellà, Juan Manuel (IOP PUBLISHING LTD, 2004-05-31)
      Article
      Accés obert
      In this work we predict the nonlinear behaviour of an eight-pole quasi-elliptic bandpass high temperature superconducting (HTS) filter with an equivalent circuit extracted from intermodulation measurements performed at the ...