@article {14_JEMWA_CORCOLES_FULL-WAVEFloquet, title = {Full-wave analysis of finite periodic cylindrical conformal arrays with Floquet spherical modes and a hybrid finite element {\textendash} generalized scattering matrix method}, journal = {Journal of Electromagnetic Waves and Applications}, volume = {28}, number = {1}, year = {2014}, month = {Jan}, pages = {102-111}, abstract = {This work reports a novel approach for the full-wave analysis of a finite conformal array made up of antennas which are periodically arranged on a metallic cylindrical surface. The analysis methodology is based on a hybrid finite element and modal analysis method, and it allows the computation of the generalized scattering matrix of the structure. In this case, spherical vector modes are used to characterize the radiating region and because of the periodic nature of the conformal array, Floquet{\textquoteright}s theory is used to render the methodology efficient and accurate. Therefore, the formulation is derived to be able to characterize the whole structure from the analysis of only one semi-period. Numerical results of arrays made up of rectangular apertures and microstrip patches are presented and compared with the ones obtained with commercial software and infinite models both for conformal and planar arrays.}, keywords = {cylindrical conformal array, finite element method, Floquet{\textquoteright}s theory, generalized scattering matrix, spherical modes}, issn = {0920-5071}, doi = {10.1080/09205071.2013.857280}, url = {http://www.tandfonline.com/doi/abs/10.1080/09205071.2013.857280$\#$.U57p9vl_vQg}, author = {J C{\'o}rcoles and Gonz{\'a}lez, M A and Zapata, J} } @conference {13_EIEC_RubioetAl_SphericalModesinCEM, title = {Spherical Modes in Computational Electromagnetics applied to Antenna Problems}, booktitle = {IX Iberian Meeting on Computational Electromagnetism}, year = {2013}, month = {May}, pages = {1}, abstract = {In this work we review the use of spherical modes in computational electromagnetics mainly applied to antenna problems. First, the theory of spherical modes will be reviewed. Second, the use jointly with the Finite Element Method will be exposed. Third, the application to the analysis of finite arrays will be shown. Finally, it will be presented how the spherical modes allow us to obtain an equivalent model of the antenna, in terms of infinitesimal dipoles, which increases the capabilities of the method for the analysis of finite arrays.}, author = {Rubio, J and Izquierdo, J F and Gonz{\'a}lez, M A and Gil, J M and Garc{\'\i}a, J and de la Rubia, V and J C{\'o}rcoles and Zapata, J} } @article {12_TAP_Corcoles_CombinedArrayThinning, title = {Efficient Combined Array Thinning and Weighting for Pattern Synthesis With a Nested Optimization Scheme}, journal = {IEEE Transactions on Antennas and Propagation}, volume = {60}, number = {11}, year = {2012}, month = {Nov}, pages = {5107-5117}, abstract = {A novel procedure to thin an antenna array which synthesizes a desired pattern with the minimum number of active elements is introduced. The proposed method yields both the active elements and their corresponding excitations of a thinned array having the minimum number of active elements needed to meet several prescribed design specifications of the radiated far-field pattern. Specifications such as achieving a minimum gain, obtaining a pattern with a maximum allowable sidelobe level or synthesizing a shaped beam pattern confined into a mask are considered. Null field directions can also be added. In order to carry out the thinning, a genetic algorithm is used, while computing the excitations is carried out through linear or quadratic programming. The procedure incorporates the generalized scattering matrix analysis of an array made up of elements whose radiated field can be expressed as a spherical mode expansion, thus taking all electromagnetic effects inherently into account. Therefore, since the presence of an element can substantially alter the array features because of mutual coupling, two types of thinning are considered: removing elements or turning them off. Numerical results of arrays made up of isotropic sources, dielectric resonator antennas and microstrip patch antennas are presented.}, keywords = {Antenna arrays, Arrays, generalized scattering matrix, Genetic algorithms, genetic algorithms (GAs), GSM, linear programming, optimization, quadratic programming (QP), spherical wave expansion, thinned arrays, Transmission line matrix methods, Vectors}, issn = {0018-926X}, doi = {10.1109/TAP.2012.2207667}, url = {http://ieeexplore.ieee.org/stamp/stamp.jsp?tp=\&arnumber=6236035}, author = {J C{\'o}rcoles and Gonz{\'a}lez, M A} } @article {11_TAP_PontesCorcoles_ModalNetworkMIMO, title = {Modal Network Model for MIMO Antenna in-System Optimization}, journal = {IEEE Transactions on Antennas and Propagation}, volume = {59}, number = {2}, year = {2011}, month = {Feb}, pages = {643-653}, abstract = {The analysis of MIMO systems is described with the aid of a novel modal network model. For this purpose the capacity performance of typical base station and mobile station antennas in a simulated macro-cellular scenario with varying antenna inter element spacings and antenna rotation will be studied. The model is based on the modal description of typical receiving and transmitting antennas. In this manner a significant simulation time reduction is achieved which allows for faster analysis and optimization. To prove this the effects of both the mobile and base station antennas are investigated. Moreover, for the more restrictive case of base station antennas, a fully modal descriptive model is proven to yield very similar results as those from measured commercial antennas. It is found that the modal approach improves simulation speed without loss of accuracy or generality. Simulations are done for the city of Karlsruhe with a three-dimensional Ray-tracing tool.}, keywords = {3D Ray-tracing tool, Antenna arrays, antenna inter element spacing, antenna optimization, antenna rotation, base station antenna, capacity performance, cellular radio, macro-cellular scenario, MIMO antenna, MIMO communication, MIMO network model, MIMO system, mobile antennas, mobile station antenna, modal network model, multiple-input multiple-output (MIMO), network theory, path-based channel models, receiving antenna, receiving antennas, spherical mode expansion, system optimization, transmitting antenna, transmitting antennas}, issn = {0018-926X}, doi = {10.1109/TAP.2010.2096179}, url = {http://ieeexplore.ieee.org/stamp/stamp.jsp?tp=\&arnumber=5654566}, author = {Pontes, J and J C{\'o}rcoles and Gonz{\'a}lez, M A and Zwick, T} } @article {11_TAP_CorcolesRubio_SphericalSynthesis, title = {Spherical-Wave-Based Shaped-Beam Field Synthesis for Planar Arrays Including the Mutual Coupling Effects}, journal = {IEEE Transactions on Antennas and Propagation}, volume = {59}, number = {8}, year = {2011}, month = {Aug}, pages = {2872-2881}, abstract = {An analytical method to synthesize shaped-beam patterns with planar arrays, based on the handling of spherical waves, is proposed. Translational Addition Theorems will be used here for two different purposes: (1) relating the spherical modes produced by each element in the array to calculate the mutual coupling effects, and (2) expressing the field radiated by each element in terms of spherical modes corresponding to the whole array, to carry out a spherical-wave synthesis procedure based on the orthogonal properties of spherical modes. This field synthesis method is based on the fact that any antenna radiated field can be expressed as a discrete series of weighted spherical vector wave functions and it only requires the a priori knowledge of the Generalized Scattering Matrix of each array element considered as isolated from the rest of the array elements.}, keywords = {antenna feeds, antenna radiated field, antenna radiation patterns, Arrays, electromagnetic coupling, electromagnetic wave scattering, field synthesis method, generalized scattering matrix, GSM, Mutual coupling, mutual coupling effect, pattern field synthesis, planar antenna arrays, planar array, planar array element, Planar arrays, S-matrix theory, Scattering, spherical wave expansion, spherical-wave synthesis procedure, spherical-wave-based shaped-beam field synthesis, translational addition theorem, translational addition theorems, weighted spherical vector wave function}, issn = {0018-926X}, doi = {10.1109/TAP.2011.2158950}, url = {http://ieeexplore.ieee.org/stamp/stamp.jsp?tp=\&arnumber=5871276}, author = {J C{\'o}rcoles and Rubio, J and Gonz{\'a}lez, M A} } @conference {10_EIEC_RubioCorcoles_SintesisAnaliticaModosEsfericos, title = {S{\'\i}ntesis anal{\'\i}tica de agrupaciones planas basada en traslaci{\'o}n de modos esf{\'e}ricos}, booktitle = {VII Iberian Meeting on Computational Electromagnetism (in Spanish)}, year = {2010}, month = {May}, pages = {1}, abstract = {Se presenta en este trabajo un m{\'e}todo anal{\'\i}tico de s{\'\i}ntesis de haz conformado en agrupaciones planas basado en la manipulaci{\'o}n de modos esf{\'e}ricos. Los teoremas de traslaci{\'o}n se utilizan para dos fines diferentes: relacionar los modos esf{\'e}ricos de cada elemento de la agrupaci{\'o}n con el fin de calcular los efectos de acoplamiento mutuo, y expresar el campo producido por cada elemento en t{\'e}rminos de modos esf{\'e}ricos de todo el conjunto para aplicar un procedimiento de s{\'\i}ntesis esf{\'e}rica basada en las propiedades ortogonales de los modos esf{\'e}ricos. Este m{\'e}todo de s{\'\i}ntesis de campo se basa en el hecho de que cualquier campo radiado de la antena puede expresarse como una serie discreta ponderada de funciones vectoriales esf{\'e}ricas y s{\'o}lo requiere el conocimiento a priori de la matriz de dispersi{\'o}n generalizada de cada elemento de la agrupaci{\'o}n considerado aislado del resto.}, author = {Rubio, J and J C{\'o}rcoles and Gonz{\'a}lez, M A} } @conference {09_EuCAP_Corcoles, title = {Array design for different SLL and null directions with an interior-point optimization method from the generalized-scattering-matrix and spherical modes}, booktitle = {Antennas and Propagation, 2009. EuCAP 2009. 3rd European Conference on}, year = {2009}, month = {March}, pages = {1381-1385}, abstract = {This paper presents a pattern synthesis technique for arbitrary planar arrays which can be characterized in terms of a generalized-scattering-matrix (GSM) and whose radiated field can be expressed as a spherical mode expansion (SME). The procedure yields the complex-valued excitations needed to achieve a pattern which fulfils the requirements of different sidelobe levels in different regions and several prescribed field nulls with a maximum directive gain. The formulation is based on matrix-valued functions which are computed from the GSM and the SME, so all interelement coupling effects coming from complex radiating structures used as array elements are inherently taken into account. To solve the resulting nonlinear optimization problem, a primal-dual interior-point filtering method specifically adapted to this formulation is developed. Numerical results are presented for arrays of microstrip patch antennas and dielectric resonator antennas.}, keywords = {antenna pattern, antenna radiation patterns, antenna sidelobe level, dielectric resonator antenna, dielectric resonator antennas, electromagnetic coupling, Filtering, filtering theory, generalized scattering matrix, generalized-scattering-matrix, GSM, Hessian matrices, interelement coupling effect, interior-point optimization method, Jacobian matrices, microstrip antenna arrays, Microstrip antennas, microstrip patch antenna, Microstrip resonators, nonlinear optimization, optimisation, Optimization methods, pattern synthesis technique, planar antenna array, planar antenna arrays, Planar arrays, primal-dual interior-point filtering method, Resonator filters, S-matrix theory, spherical, spherical mode expansion, Transmission line matrix methods, wave expansion}, url = {http://ieeexplore.ieee.org/stamp/stamp.jsp?tp=\&arnumber=5067872}, author = {J C{\'o}rcoles and Gonz{\'a}lez, M A and Rubio, J and Zapata, J} } @article {09_TAP_Corcoles_FourierSynthesis, title = {Fourier Synthesis of Linear Arrays Based on the Generalized Scattering Matrix and Spherical Modes}, journal = {IEEE Transactions on Antennas and Propagation}, volume = {57}, number = {7}, year = {2009}, month = {July}, pages = {1944-1951}, abstract = {This paper presents a novel, simple pattern synthesis procedure for linear equispaced arrays which can be characterized by a generalized scattering matrix (GSM) and whose radiated field can be expressed as a weighted sum of shifted spherical waves. It can be viewed as an extension of the classic design techniques of the Fourier series (FS) method or the Woodward-Lawson frequency sampling method, to the case in which the individual antenna elements{\textquoteright} patterns and all interelement couplings are taken into account. The design procedure, which yields the excitations needed to achieve the desired pattern, is based on either the FS or the discrete Fourier transform (DFT) of the spherical mode expansion of the array radiated field, as well as on various properties associated to the FS or DFT coefficients. In this work, to compute the GSM of the array and the spherical mode expansion of the field, a validated hybrid full-wave methodology, based on the finite element method and rotation and translation properties of spherical waves, is used. Numerical results of different synthesized array patterns are presented for different arrays made up of dielectric resonator antennas and cavity-backed microstrip circular patches.}, keywords = {Antenna array mutual coupling, cavity-backed microstrip circular patches, dielectric resonator antennas, discrete Fourier transform, discrete Fourier transforms, discrete Fourier transforms (DFT), finite element analysis, finite element method, finite element methods, Fourier series, Fourier synthesis, Frequency, generalized scattering matrix, GSM, interelement couplings, linear antenna arrays, linear arrays, linear equispaced arrays, microstrip antenna arrays, Microstrip antennas, pattern synthesis, S-matrix theory, Sampling methods, Scattering, scattering matrices, shifted spherical waves, signal sampling, spherical mode expansion, spherical modes, Transmission line matrix methods, Woodward-Lawson frequency sampling}, issn = {0018-926X}, doi = {10.1109/TAP.2009.2021929}, url = {http://ieeexplore.ieee.org/stamp/stamp.jsp?tp=\&arnumber=4907114}, author = {J C{\'o}rcoles and Gonz{\'a}lez, M A and Rubio, J} } @article {09_ELL_Corcoles_LPfromGSM, title = {Linear programming from generalised scattering matrix analysis of array for minimum sidelobe level and prescribed nulls}, journal = {Electronics Letters}, volume = {45}, number = {1}, year = {2009}, month = {January}, pages = {9-10}, abstract = {A pattern synthesis technique for arbitrary planar arrays which are characterised in terms of a generalised scattering matrix and whose radiated field is expressed as a spherical mode expansion is introduced. The procedure yields the complex-valued excitations to achieve a minimum-maximum sidelobe level given a specified pointing direction and mainlobe width, as well as prescribed field nulls. All inter-element coupling effects coming from complex radiating structures used as array elements are inherently taken into account. Numerical results are presented for arrays of dielectric resonator antennas.}, keywords = {Antenna arrays, arbitrary planar arrays, complex-valued excitations, dielectric resonator antennas, dielectric resonators, electromagnetic coupling, electromagnetic wave scattering, generalised scattering matrix analysis, inter-element coupling effects, linear programming, minimum sidelobe level array, minimum-maximum sidelobe level, pattern synthesis technique, prescribed nulls}, issn = {0013-5194}, doi = {10.1049/el:20092008}, url = {http://ieeexplore.ieee.org/stamp/stamp.jsp?tp=\&arnumber=4733076}, author = {J C{\'o}rcoles and Gonz{\'a}lez, M A and Zapata, J} } @article {09_ELL_Corcoles_ModellingLOScoupledMIMO, title = {Modelling line-of-sight coupled MIMO systems with generalised scattering matrices and spherical wave translations}, journal = {Electronics Letters}, volume = {45}, number = {12}, year = {2009}, month = {June}, pages = {598-599}, abstract = {A model to rigorously characterise line-of-sight MIMO systems is introduced. It is based on the generalised scattering matrix of each antenna, considered as isolated, and the rotation and translation coefficients of spherical modes. The resulting channel matrix rigorously includes the exact spherical vector nature of electromagnetic propagation (which may exert a significant influence over short-range links), mutual coupling effects and real antenna reflection, transmission, reception and scattering features. Numerical results are presented for MIMO systems made up of ideal dipoles.}, keywords = {antenna reflection, channel matrix, electromagnetic coupling, electromagnetic propagation, electromagnetic wave propagation, generalised scattering matrix, line-of-sight coupled MIMO system, MIMO communication, multiple-input multiple-output system, mutual coupling effect, S-matrix theory, spherical wave translation scheme}, issn = {0013-5194}, doi = {10.1049/el.2009.0545}, url = {http://ieeexplore.ieee.org/stamp/stamp.jsp?tp=\&arnumber=5069759}, author = {J C{\'o}rcoles and Pontes, J and Gonz{\'a}lez, M A and Zwick, T} } @conference {09_APS_Corcoles_MultibeamLP, title = {Multibeam synthesis with minimum SLL through linear programming from the GSM-analysis of an array}, booktitle = {Antennas and Propagation Society International Symposium, 2009. APSURSI {\textquoteright}09. IEEE}, year = {2009}, month = {June}, pages = {1-4}, abstract = {The application of all sort of optimization techniques to different array pattern synthesis problems has been widely studied since the early days of antenna array design. Most of these works (generally having constraints on the array configuration) take for granted several assumptions, among which one can highlight considering isotropic sources and not taking into account coupling between array elements. Great advances have been achieved in the field of computational electromagnetics which allow complex radiating structures, including finite antenna arrays, to be analyzed from a full-wave approach inherently taking into account all electromagnetic effects. Recently, new techniques for the afore-mentioned pattern synthesis problems with the inclusion of this rigourous electromagentic (EM) analysis have been developed. In this work, the authors propose an EM-based design technique which yields the excitations of an arbitraty planar array to output a field pattern with minimum maximum sidelobe level (SLL) given the directions of various main beams with specified mainlobe widths and different relative amplitudes and phase differences. The array is characterized through a generalized scattering matrix (GSM) and its radiated field is expressed as a spherical mode expansion (SME). The accurate determination of the array GSM is needed to have it rigourously characterized, so the use of a full-wave technique is required in case complex antenna elements or arbitrary array configurations are considered. We develop the formulation to arrive at a standard linear programming (LP) problem. Numerical results of a linear array of dielectric resonator antennas (DRA{\textquoteright}s) are presented.}, keywords = {Antenna arrays, array pattern synthesis, complex radiating structures, computational electromagnetics, Design optimization, dielectric resonator antennas, electromagentic analysis, Electromagnetic analysis, electromagnetic fields, Electromagnetic radiation, electromagnetic waves, generalized scattering matrix, GSM, linear antenna arrays, linear programming, minimum maximum sidelobe level, multibeam antennas, multibeam synthesis, optimization, S-matrix theory, SME, spherical mode expansion}, issn = {1522-3965}, doi = {10.1109/APS.2009.5171513}, url = {http://ieeexplore.ieee.org/stamp/stamp.jsp?tp=\&arnumber=5171513}, author = {J C{\'o}rcoles and Gonz{\'a}lez, M A} } @article {09_TAP_Corcoles_MultiobjectiveOptimization, title = {Multiobjective Optimization of Real and Coupled Antenna Array Excitations via Primal-Dual, Interior Point Filter Method From Spherical Mode Expansions}, journal = {IEEE Transactions on Antennas and Propagation}, volume = {57}, number = {1}, year = {2009}, month = {Jan}, pages = {110-121}, keywords = {antenna array, Antenna arrays, Apertures, dielectric resonator antennas, Filters, generalized scattering matrix, Hessian matrices, Jacobian matrices, Lighting, matrix-valued functions, maximum crosspolar level, microstrip antenna arrays, Microstrip antennas, microstrip patch array, minimum aperture illumination efficiency, multiobjective optimization, optimisation, Optimization methods, planar antenna arrays, planar array excitations, Planar arrays, primal-dual interior point method, spherical mode expansions, spherical wave expansion, Transmission line matrix methods}, issn = {0018-926X}, doi = {10.1109/TAP.2008.2009727}, url = {http://ieeexplore.ieee.org/stamp/stamp.jsp?tp=\&arnumber=4797974}, author = {J C{\'o}rcoles and Gonz{\'a}lez, M A and Rubio, J} } @article {09_AWPL_Corcoles_MutualCouplingCompensation, title = {Mutual Coupling Compensation in Arrays Using a Spherical Wave Expansion of the Radiated Field}, journal = {IEEE Antennas and Wireless Propagation Letters}, volume = {8}, year = {2009}, pages = {108-111}, abstract = {This letter presents a flexible method to compensate the interelement mutual coupling (MC) effects that may degrade the field pattern of an array of real and coupled antennas. A closed-expression for a mutual coupling compensation matrix (MCCM) is derived. The MCCM is used to compensate the presence of the real individual elements{\textquoteright} patterns and the interelement MC effects for any excitations obtained with an isotropic-based pattern synthesis method. The MCCM is calculated from the generalized scattering matrix (GSM) of an antenna array and the spherical mode expansion (SME) of its radiated field. For a given array, this MCCM has to be calculated only once since it only depends on the radiating and scattering characteristics of the antenna elements as well as on their location in the array. Conditions regarding null field pattern directions can also be reinforced in the MCCM. To compute the GSM of the array and the SME of the radiated field, a validated full-wave hybrid and modular methodology is used. Numerical results of synthesized patterns where the MC effects have been compensated are presented for arrays made up of dielectric resonator antennas.}, keywords = {antenna array, Antenna array mutual coupling, Antenna arrays, antenna radiation patterns, dielectric resonator antennas, electromagnetic coupling, field pattern, field radiation, generalized scattering matrix, interelement mutual coupling effect, isotropic-based pattern synthesis method, modular methodology, mutual coupling compensation matrix, Planar arrays, quadratic programming, S-matrix theory, scattering matrices, spherical wave expansion}, issn = {1536-1225}, doi = {10.1109/LAWP.2008.2012276}, url = {http://ieeexplore.ieee.org/stamp/stamp.jsp?tp=\&arnumber=4745777}, author = {J C{\'o}rcoles and Gonz{\'a}lez, M A and Rubio, J} } @article {09_IntJRFMiCAE_CORCOLES_PerformanceUslot, title = {Performance characterization of wideband, wide-angle scan arrays of cavity-backed U-slot microstrip patch antennas}, journal = {International Journal of RF and Microwave Computer-Aided Engineering}, volume = {19}, number = {3}, year = {2009}, pages = {389{\textendash}396}, abstract = {This work looks at the use of wideband cavity-backed U-slot microstrip antennas in finite phased arrays. This configuration retains the single-patch and single-layer characteristics of conventional microstrip antenna arrays and provides a good impedance matching over wider scan angles when electrically thick substrates are used to improve the frequency bandwidth. The characteristics of finite phased arrays of U-slot rectangular microstrip patches enclosed in cylindrical cavities are analyzed from a validated hybrid methodology based on the finite element method, the modal analysis, and the properties of spherical waves. The results are compared with those obtained using an infinite array model. {\textcopyright} 2008 Wiley Periodicals, Inc. Int J RF and Microwave CAE, 2009.}, keywords = {broadband U-slot patch antenna, cavity-backed microstrip antennas, finite element method, finite phased array, spherical mode expansion}, issn = {1099-047X}, doi = {10.1002/mmce.20361}, url = {http://dx.doi.org/10.1002/mmce.20361}, author = {J C{\'o}rcoles and Gonz{\'a}lez, M A and Rubio, J and Zapata, J} } @conference {09_URSIESP_Corcoles_SintesisdeFourier, title = {S{\'\i}ntesis de Fourier para agrupaciones lineales de antenas reales y acopladas}, booktitle = {Proc. 2009 Simposium Nacional URSI (in Spanish)}, year = {2009}, month = {Sep}, pages = {1-4}, abstract = {This work presents a novel and simple pattern synthesis procedure for lineal and equispaced arrays that considers real individual antenna elements{\textquoteright} patterns and includes the mutual coupling between elements. It is an extension of the classic design techniques of the Fourier series method or the Woodward-Lawson frequency sampling method based on the expansion of the radiated field of the individual array elements in spherical modes, and the characterization of the whole array from a generalized scattering matrix}, author = {J C{\'o}rcoles and Gonz{\'a}lez, M A and Rubio, J} } @article {08_MOPT_CORCOLES_CADstackedpatches, title = {Cad of stacked patch antennas through multipurpose admittance matrices from FEM and neural networks}, journal = {Microwave and Optical Technology Letters}, volume = {50}, number = {9}, year = {2008}, month = {Sep}, pages = {2411-2416}, abstract = {In this work, a novel computer-aided design methodology for probe-fed, cavity-backed, stacked microstrip patch antennas is proposed. The methodology incorporates the rigor of a numerical technique, such as finite element methods, which, in turn, makes use of a newly developed procedure (multipurpose admittance matrices) to carry out a full-wave analysis in a given structure in spite of certain physical shapes and dimensions not yet being established. With the aid of this technique, we form a training set for a neural network, whose output is the desired response of the antenna according to the value of design parameters. Last, taking advantage of this neural network, we perform a global optimization through a genetic algorithm or simulated annealing to obtain a final design. The proposed methodology is validated through a real design whose numerical results are compared with measurements with good agreement.}, keywords = {computer-aided design, finite element methods, neural networks, optimization algorithms, stacked microstrip antennas}, issn = {1098-2760}, doi = {10.1002/mop.23670}, url = {http://onlinelibrary.wiley.com/doi/10.1002/mop.23670/abstract}, author = {J C{\'o}rcoles and Gonz{\'a}lez, M A and Zapata, J} } @conference {08_URSIESP_Corcoles_DisenoAutomatizadoParches, title = {Dise{\~n}o automatizado de antenas de parches apilados en cavidad mediante descomposici{\'o}n de dominio en el MEF, redes neuronales y optimizaci{\'o}n global}, booktitle = {Proc. 2008 Simposium Nacional URSI (in Spanish)}, year = {2008}, month = {Sep}, pages = {1-4}, abstract = {This work reports the development of a computeraided- design methodology consisting of three steps for probe-fed cavity-backed, stacked microstrip patch antennas. In the first step, the rigour of a numerical technique such as the finite element method (FEM) to describe the electromagnetic behaviour of these structures is incorporated. The application of the FEM is carried out on a highly efficient basis through a sophisticated domain decomposition approach. From these results, a neural network (NN) is trained to output the desired response of the antenna according to the value of design parameters. Thanks to the versatily of this NN, a global optimization through simulated annealing or genetic algorithms is lastly executed to obtain a final design. The proposed methodology is validated through a real design whose numerical results are compared with measurements with good agreement.}, author = {J C{\'o}rcoles and Gonz{\'a}lez, M A and Zapata, J} } @conference {08_EIEC_CorcolesetAl_OptimizationIPM, title = {Optimization of coupled antenna arrays characterized by spherical modes by means of an interior-point filtering method}, booktitle = {VI Iberian Meeting on Computational Electromagnetism}, year = {2008}, month = {Oct}, pages = {1}, abstract = {In this work, we present a novel method for the efficient optimization of arbitrary planar array excitations. This method, which inherently takes into account every array element pattern as well as all interelement couplings, allows the maximization of the directive or power gain of an arbitrary planar array scanned at whichever direction, subject to constraints on the maximum sidelobe level, the maximum crosspolar level, the minimum aperture illumination efficiency, the setting of null pointing directions or a dynamic range ratio control. Numerical examples of arrays with canonical geometries, composed of microstrip patches or dielectric resonator antennas and covering a wide variety of requirements are presented.}, author = {J C{\'o}rcoles and Gonz{\'a}lez, M A and Rubio, J and Zapata, J} }