Now showing items 1-20 of 86

  • Accurate numerical modeling of the TARA reflector system 

    Heldring, Alexander; Rius Casals, Juan Manuel; Ligthart, Leo P.; Cardama Aznar, Ángel (IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC, 2004-07-31)
    Article
    Open Access
    The radiation pattern of the large parabolic reflectors of the Transportable Atmospheric RAdar system (TARA), developed at Delft University of Technology, has been accurately simulated. The electric field integral ...
  • Active microwave sensing of highly contrasted dielectric bodies 

    Broquetas Ibars, Antoni; Mallorquí Franquet, Jordi Joan; Rius Casals, Juan Manuel; Jofre Roca, Lluís; Cardama Aznar, Ángel (1993-11)
    Article
    Restricted access - publisher's policy
    In this work the active tomographic imaging of biological bodies which exhibits a high dielectric contrast is studied. Two approaches based on the Born approximation are presented: a differential reconstruction method which ...
  • A cylindrical array for fast microwave tomography 

    de los Reyes, Elías; Jofre Roca, Lluís; Broquetas Ibars, Antoni; Elias Fusté, Antoni; Cardama Aznar, Ángel (Unión Científica Internacional de Radio (URSI), 1987)
    Conference report
    Open Access
  • Admitancia de entrada de una guía rectangular rellena de dieléctrico 

    Jofre Roca, Lluís; Ferrando Bataller, Miquel; Cardama Aznar, Ángel (Unión Científica Internacional de Radio (URSI), 1983)
    Conference report
    Open Access
    A variational formulation, based in a plane wave angular decomposition, is developped for the admitance of a rectangular dielectric-filled waveguide, radiating in a half space.
  • Algoritmo iterativo de propagación espectral para el cálculo de RCS en cavidades conductoras 

    Rius Casals, Juan Manuel; Cardama Aznar, Ángel; Jofre Roca, Lluís (1992)
    Conference report
    Open Access
    One of the most difficult problems in the RCS prediction of a complex target is the analysis of the cavities existing at the air inlets and outlets of engines. The geometrical complexity of these structures makes difficult ...
  • Algoritmos para el cálculo de los campos lejanos radiados por antenas, a partir de medidas en campo próximo 

    Jofre Roca, Lluís; Cardama Aznar, Ángel (1980)
    Conference report
    Open Access
    We present the principles of operation of near field antenna ranges and general expressions for the calculation of the far field, from measurements on plane surfaces, focusing on the limitations of the different aproaches. ...
  • Análisis de antenas de reflector mediante procesado gráfico 

    Vall-Llossera Ferran, Mercedes Magdalena; Salazar, C; Rius Casals, Juan Manuel; Cardama Aznar, Ángel (Universidad de Valladolid, 1995)
    Conference report
    Open Access
    The aim of this article is to show a new technique for calculating the Radiation Pattern of arbitrary geometry reflector antennas. We use the Graphical processing technique developed in this group for Radar Cross Section ...
  • Análisis de antenas parabólicas 

    Jofre Roca, Lluís; Cardama Aznar, Ángel (1981)
    Conference report
    Open Access
    This paper describes a set of procedures for computing secondary patterns of parabolic-reflector antennas. Once the primary feed radiation pattern is defined, aperture-plane fields are computed for a grid of points using ...
  • Análisis de guías parcialmente rellenas de dieléctrico mediante el método de los elementos finitos 

    Ferrando Bataller, Miquel; Cruellas Ibarz, Juan Carlos; Cardama Aznar, Ángel; Jofre Roca, Lluís (Unión Científica Internacional de Radio (URSI), 1983)
    Conference report
    Open Access
    The finite element's method is aplied to the study of inhomogenous waveguides of arbitrary cross-section. The fields in the guide are - expanded in a series of bidimensional functions, obtaining a variational expression ...
  • Analysis of electrically large concave scatterers with the integral equation mei 

    Rius Casals, Juan Manuel; Carpintero, C Pérez; Cardama Aznar, Ángel; Michalski, Krzysztof (1997-04)
    Article
    Restricted access - publisher's policy
    The integral equation MEI (IE-MEI) is a new, sparse matrix formulation of the boundary-element method, which is particularly well suited for large convex scatterers. In this Letter we explain why the original implementation ...
  • Analysis of reflector and horn antennas using multilevel fast multipole algorithm 

    Heldring, Alexander; Rius Casals, Juan Manuel; Parrón Granados, Josep; Cardama Aznar, Ángel; Ligthart, L P (CIMNE, 2000)
    Conference report
    Open Access
    The MultiLevel Fast Multipole Algorithm (MLFMA) has been implemented in a Method of Moments code for arbitrarily shaped metal surfaces discretized in Rao, Wilton and Glisson (RWG) basisfunctions. The accuracy of the ...
  • An approximate expression to estimate signal-to-noise improvement in cylindrical near-field measurements 

    Romeu Robert, Jordi; Jofre Roca, Lluís; Cardama Aznar, Ángel (IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC, 1994-07-01)
    Article
    Open Access
    A very simple approximate expression for the process gain (PG) for the cylindrical case is derived. The different approximations and assumptions required to obtain this expression are shown. This expression might be useful ...
  • A near field spherical wave inverse synthetic aperture radar technique 

    Broquetas Ibars, Antoni; Jofre Roca, Lluís; Cardama Aznar, Ángel (Institute of Electrical and Electronics Engineers (IEEE), 1992)
    Conference report
    Open Access
    The authors present an imaging near-field spherical wave inverse synthetic aperture radar (SWISAR) algorithm based on a focusing operator of the scattered fields on the target surface. A spherical wave can be easily generated ...
  • Antenas 

    Cardama Aznar, Ángel; Jofre Roca, Lluís; Rius Casals, Juan Manuel; Romeu Robert, Jordi; Blanch Boris, Sebastián; Ferrando Bataller, Miguel (Edicions UPC, 2002)
    Book
    Restricted access to UB, UAB, UPC, UPF, UdG, UdL, URV, UOC, BC, UVic, UJI, URL, UIC users
    En este libro se presentan los métodos fundamentales de análisis de antenas con un nivel de detalle que permite comprender sus principios de funcionamiento y conocer los parámetros de diseño que son de interés práctico. ...
  • Antenas centenarias 

    Cardama Aznar, Ángel (Escola Tècnica Superior d'Enginyers de Telecomunicació de Barcelona, 1994)
    Article
    Open Access
  • Antenas de ranura en el plano de masa de una línea stripline 

    Ferrando Bataller, Miquel; Cardama Aznar, Ángel (1980)
    Conference report
    Open Access
    A theoretical analysis of slot antennas excited by stripline is presented, with calculation of impedance and resonance frequency for different positions of the slot. Mutual effects are taken into account and results for ...
  • Antenas: ¿ha cambiado algo en ellas en este siglo? 

    Cardama Aznar, Ángel (1998)
    Conference report
    Open Access
  • Antenas para radio y TV. Principios de funcionamiento y características técnicas 

    Cardama Aznar, Ángel; Jofre Roca, Lluís (1980-09)
    Article
    Restricted access - publisher's policy
    Existe una gran variedad de antenas utilizadas satisfactoriamente como transmisoras y receptoras y aunque en cada banda de frecuencias existe una gran especialización de los tipos empleados, todas ellas operan sobre ...
  • Application of the conjugate gradient method to a self-matching network for industrial microwave heating antennas 

    Mallorquí Franquet, Jordi Joan; Aguasca Solé, Alberto; Cardama Aznar, Ángel; Pages, R; Haro, J M (Institute of Electrical and Electronics Engineers (IEEE), 1999)
    Conference report
    Open Access
    One of the main problems regarding the efficiency in a heating industrial system using high power microwaves is related with the uncontrolled changes on the load. These changes can be caused both by the different kinds of ...
  • Automatic self-matching network for industrial microwave heating based on the conjugate gradient algorithm 

    Mallorquí Franquet, Jordi Joan; Aguasca Solé, Alberto; Cardama Aznar, Ángel; Pagès Serra, Romà; Haro Sánchez, Jose (IEE-INST ELEC ENG, 1999-02-28)
    Article
    Open Access
    An automatic matching network has been implemented using a waveguide magic T with two sliding short circuit stubs whch are adjusted by a microcontroller running a conjugate gradient algorithm. The inclusion of this device ...