Ara es mostren els items 1-20 de 68

    • A GPU parallel randomized CUR compression method for the Method of Moments 

      López Menchón, Héctor; Heldring, Alexander; Úbeda Farré, Eduard; Rius Casals, Juan Manuel (2023-06-01)
      Article
      Accés restringit per política de l'editorial
      In this work, we propose a GPU parallel implementation of the randomized CUR (or Pseudo Skeleton) Approximation to compress the -matrices of linear systems that arise in the discretization of integral equations modeling ...
    • A microwave invisibility cloak: the design, simulation, and measurement of a simple and effective frequency-selective surface-based mantle cloak 

      Yuste, Pedro; Rius Casals, Juan Manuel; Romeu Robert, Jordi; Blanch Boris, Sebastián; Heldring, Alexander; Úbeda Farré, Eduard (2018-06-26)
      Article
      Accés obert
      In recent years, there has been a growing interest in developing invisibility cloaks that can conceal an object. These techniques are often based either on coating a dielectric or conducting object with a homogeneous ...
    • A Monte Carlo method for solving the electromagnetic scattering problem in dielectric bodies with massive parallelization 

      López Menchón, Héctor; Rius Casals, Juan Manuel; Úbeda Farré, Eduard; Heldring, Alexander (Unión Científica Internacional de Radio (URSI), 2021)
      Text en actes de congrés
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      In this work, we develop a novel Monte Carlo method for solving the electromagnetic scattering problem. The method is based on a formal representation of the solution as a modified Born series whose coefficients are found ...
    • A parallel Monte Carlo method for solving electromagnetic scattering in clusters of dielectric objects 

      López Menchón, Héctor; Úbeda Farré, Eduard; Heldring, Alexander; Rius Casals, Juan Manuel (Elsevier, 2022-08-15)
      Article
      Accés restringit per política de l'editorial
      In this work, we develop a novel Monte Carlo method for solving the electromagnetic scattering problem for clusters of photonic particles. The method is based on a formal solution of the scattering problem as a modified ...
    • A recursive acceleration technique for static potential Green's functions of a rectangular cavity combining image and modal series 

      Tamayo Palau, José María; López-Peña, Sergio; Mattes, Michael; Heldring, Alexander; Rius Casals, Juan Manuel; Mosig, Juan Ramón (2011-03)
      Article
      Accés restringit per política de l'editorial
      A hybrid acceleration algorithm for the computation of the static potential Green’s functions of a rectangular cavity is proposed. Similarly to Ewald’s method, it combines the series expansions in terms of images and modes. ...
    • A simple and effective microwave invisibility cloak based on frequency selective surfaces 

      Yuste, Pedro; Rius Casals, Juan Manuel; Romeu Robert, Jordi; Blanch Boris, Sebastián; Heldring, Alexander; Úbeda Farré, Eduard (Institute of Electrical and Electronics Engineers (IEEE), 2017)
      Comunicació de congrés
      Accés obert
      This paper presents the design, simulation, manufacturing and testing of a simple invisibility cloak based on a frequency selective surface (FSS). The work is focused on cloaking an electrically thin dielectric cylinder ...
    • Accelerated direct solution of the method-of-moments linear system 

      Heldring, Alexander; Tamayo, J.M.; Úbeda Farré, Eduard; Rius Casals, Juan Manuel (2012-08)
      Article
      Accés restringit per política de l'editorial
      This paper addresses the direct (noniterative) solution of the method-of-moments (MoM) linear system, accelerated through block-wise compression of the MoM impedance matrix. Efficient matrix block compression is achieved ...
    • Accelerated direct solution of the MoM linear system using block compression and nested factorization 

      Heldring, Alexander; Rius Casals, Juan Manuel (IEEE, 2011)
      Text en actes de congrés
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      A comparison is presented between different algorithms for direct (non-iterative) accelerated solution of the Method of Moments. The alternatives are common block LU factorization and Compressed Block Decomposition (CBD), ...
    • Accelerated direct solution of the MoM-VIE for dielectric scatterers 

      Heldring, Alexander; Tamayo Palau, José María; Rius Casals, Juan Manuel; Úbeda Farré, Eduard (2011)
      Text en actes de congrés
      Accés obert
      The Multiscale Compressed Block Decomposition algorithm (MS-CBD), a direct (non-iterative) linear solver, is applied to accelerate the solution of the MoM-VIE formulation for dielectric scatterers. Numerical solutions are ...
    • Acceleration of Born series by change of variables 

      López Menchón, Héctor; Rius Casals, Juan Manuel; Heldring, Alexander; Úbeda Farré, Eduard (2021-09)
      Article
      Accés obert
      In this work, we propose a method to enhance the convergence of the Born series. The Born series is widely used in scattering theory, but its convergence is only guaranteed under certain restrictive conditions which limit ...
    • 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
      Accés obert
      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 ...
    • Accurate, grid-robust and versatile combined-field discretization for the electromagnetic scattering analysis of perfectly conducting targets 

      Úbeda Farré, Eduard; Sekulic, Ivan; Rius Casals, Juan Manuel; Heldring, Alexander (2020-04-15)
      Article
      Accés obert
      Recent implementations of the Electric-Field Integral Equation (EFIE) for the electromagnetic scattering analysis of perfectly conducting targets rely on the electric current expansion with the monopolar-RWG basis functions, ...
    • Adapted ACA algorithm with improved efficiency and compression rate 

      Heldring, Alexander; Úbeda Farré, Eduard; Rius Casals, Juan Manuel (2015)
      Text en actes de congrés
      Accés obert
      This contribution proposes an adapted version of the popular Adaptive Cross Approximation algorithm for block wise compression of Method of Moments impedance matrices. The estimation of the matrix block ...
    • Analysis of microstrip antennas by multilevel matrix decomposition algorithm 

      Parrón Granados, Josep; Rius Casals, Juan Manuel; Heldring, Alexander; Úbeda Farré, Eduard; Mosig, Juan R (ESA, 1999)
      Text en actes de congrés
      Accés obert
      Integral equation methods (IE) are widely used in conjunction with Method of Moments (MoM) discretization for the numerical analysis of microstrip antennas. However, their application to large antenna arrays is difficult ...
    • 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)
      Text en actes de congrés
      Accés obert
      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 ...
    • Application of Multilevel Adaptive Cross Approximation (MLACA) to electromagnetic scattering and radiation problems 

      Tamayo Palau, José María; Heldring, Alexander; Rius Casals, Juan Manuel (2009-09-14)
      Text en actes de congrés
      Accés obert
    • Compression of the MoM matrix using macrobasis functions with a full-controlable accuracy 

      Tamayo Palau, José María; Heldring, Alexander; Rius Casals, Juan Manuel (EurAPP, 2009)
      Text en actes de congrés
      Accés obert
      A new accuracy-controlable method for compressing the MoM impedance matrix of an electromagnetic problem based on a basis change plus a truncation with a threshold is presented here. The idea is to switch to singular basis ...
    • Creació de recursos en línea per a l’autoaprenentage, foment de l’esperit crític i emprenedor i formació d’un comité d’avaluació externa en el màster MERIT 

      Pradell i Cara, Lluís; Cabrera-Bean, Margarita; Canal Bienzobas, Fernando; Cardama Aznar, Ángel; Gasull Llampallas, Antoni; González Arbesú, José María; Giró Nieto, Xavier; Heldring, Alexander; Herranz Luis, Jaime; Jofre Roca, Lluís; Mallorquí Franquet, Jordi Joan; Nadeu Camprubí, Climent; Olmos Bonafé, Juan José; Romeu Robert, Jordi; Rius Casals, Juan Manuel; Torres Torres, Francisco; Úbeda Farré, Eduard; Coderch Collell, Marcel; Kerans, Mary Ellen; Ros Giralt, Jordi; García, Antonio; González Font, Blanca; Guardiola Garcia, Marta; Hernández, Antoni; Melgarejo, Natali; Mestres, Albert (2009-02-12T10:25:51Z)
      Comunicació de congrés / Text en actes de congrés
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      El projecte es desenvolupa en el marc de la titulació oficial de màster MERIT del Departament de Teoria del Senyal i Comunicacions. El màster, orientat a la recerca i integrat dins del programa Erasmus Mundus, presenta ...
    • Discretization of the EFIE in Method of Moments without continuity of the normal current component across edges 

      Úbeda Farré, Eduard; Rius Casals, Juan Manuel; Heldring, Alexander (Institute of Electrical and Electronics Engineers (IEEE), 2013)
      Text en actes de congrés
      Accés restringit per política de l'editorial
      The discretization in Method of Moments (MoM) of the Electric-Field Integral Equation (EFIE) is traditionally carried out by preserving the continuity of the normal component in the expansion of the current across the ...
    • Edge diffraction computation using GRECO 

      Rius Casals, Juan Manuel; Carbo, Alex; Úbeda Farré, Eduard; Heldring, Alexander (Institute of Electrical and Electronics Engineers (IEEE), 2016)
      Text en actes de congrés
      Accés restringit per política de l'editorial
      This paper addresses two graphical processing approaches for computation of edge scattering with Physical Theory of Diffraction (PTD) high-frequency approximation. One is based on processing only a bitmap containing an ...