2008 |
Navarro-Tapia, M; Esteban, J; Camacho-Peñalosa, C Analysis of Slotted Antennas on Metamaterial Waveguides Artículo en actas Proceedings of the VI Iberian Meeting on Computational Electromagnetics (EIEC), Chiclana de la Frontera, Cádiz (Spain), 2008. @inproceedings{NavarroTapia2008a, title = {Analysis of Slotted Antennas on Metamaterial Waveguides}, author = {M Navarro-Tapia and J Esteban and C Camacho-Peñalosa}, year = {2008}, date = {2008-10-01}, booktitle = {Proceedings of the VI Iberian Meeting on Computational Electromagnetics (EIEC)}, address = {Chiclana de la Frontera, Cádiz (Spain)}, abstract = {Using metamaterial concepts, new leaky-wave antennas have been proposed, that exhibit novel frequency scanning capabilities, such as radiation within de backward quadrant, including broadside. A procedure to analyze slots as radiant elements in metamaterial-based waveguides is described. It involves the use of a finite-element-method commercial tool, HFSS. Some difficulties are found when applying it to the analysis of an anisotropic-magnetic-plasma medium, that are herein exposed and discussed. A simple example of leaky-wave antenna is eventually analyzed and far-field radiation properties are shown.}, keywords = {}, pubstate = {published}, tppubtype = {inproceedings} } Using metamaterial concepts, new leaky-wave antennas have been proposed, that exhibit novel frequency scanning capabilities, such as radiation within de backward quadrant, including broadside. A procedure to analyze slots as radiant elements in metamaterial-based waveguides is described. It involves the use of a finite-element-method commercial tool, HFSS. Some difficulties are found when applying it to the analysis of an anisotropic-magnetic-plasma medium, that are herein exposed and discussed. A simple example of leaky-wave antenna is eventually analyzed and far-field radiation properties are shown. |
Page, J E; Esteban, J Time Domain Dosimetry in Layered Media Artículo en actas 38th European Microwave Conference (EuMC), pp. 79 -82, Amsterdam (Denmark), 2008. @inproceedings{Page2008b, title = {Time Domain Dosimetry in Layered Media}, author = {J E Page and J Esteban}, doi = {10.1109/EUMC.2008.4751391}, year = {2008}, date = {2008-10-01}, booktitle = {38th European Microwave Conference (EuMC)}, pages = {79 -82}, address = {Amsterdam (Denmark)}, abstract = {The rigorous solution of the interaction of amplitude-modulated plane waves with planar and spherical stratified obstacles formed by lossy dispersive dielectrics is presented. Some particular cases of interest for the study of the interaction of pulsed fields and biological tissue phantoms are considered. The problem of the energy deposition is presented including some discussion about the use of the absorption rate concept.}, keywords = {}, pubstate = {published}, tppubtype = {inproceedings} } The rigorous solution of the interaction of amplitude-modulated plane waves with planar and spherical stratified obstacles formed by lossy dispersive dielectrics is presented. Some particular cases of interest for the study of the interaction of pulsed fields and biological tissue phantoms are considered. The problem of the energy deposition is presented including some discussion about the use of the absorption rate concept. |
Carrasco, Eduardo; Arrebola, Manuel; Encinar, Jose A; Barba, Mariano Demonstration of a Shaped Beam Reflectarray Using Aperture-Coupled Delay Lines for LMDS Central Station Antenna Artículo de revista IEEE TRANSACTIONS ON ANTENNAS AND PROPAGATION, 56 (10), pp. 3103-3111, 2008, ISSN: 0018-926X. @article{Carrasco2008, title = {Demonstration of a Shaped Beam Reflectarray Using Aperture-Coupled Delay Lines for LMDS Central Station Antenna}, author = {Eduardo Carrasco and Manuel Arrebola and Jose A Encinar and Mariano Barba}, doi = {10.1109/TAP.2008.929452}, issn = {0018-926X}, year = {2008}, date = {2008-10-01}, journal = {IEEE TRANSACTIONS ON ANTENNAS AND PROPAGATION}, volume = {56}, number = {10}, pages = {3103-3111}, abstract = {A shaped-beam reflectarray based on patches, aperture-coupled to delay lines is demonstrated for local multipoint distribution system (LMDS) central station antennas, in the 10.10-10.70 GHz hand. The antenna roost cover a 60 degrees-sector in azimuth with a squared cosecant pattern in elevation. The design process consists of two steps. First, a phase-only pattern synthesis technique is applied to obtain the required phase-shift distribution on the reflectarray surface which generates the shaped pattern. The second stage consists of determining the length of the delay lines. aperture-coupled to the square patches, in order to achieve the phase distribution synthesized in the previous step. Two reflectarray antennas have been designed, one for vertical (V) and the other for horizontal (H) polarization. A breadboard for V-polarization has been manufactured and tested in an anechoic chamber. showing a good agreement between theoretical and measured radiation patterns.}, keywords = {}, pubstate = {published}, tppubtype = {article} } A shaped-beam reflectarray based on patches, aperture-coupled to delay lines is demonstrated for local multipoint distribution system (LMDS) central station antennas, in the 10.10-10.70 GHz hand. The antenna roost cover a 60 degrees-sector in azimuth with a squared cosecant pattern in elevation. The design process consists of two steps. First, a phase-only pattern synthesis technique is applied to obtain the required phase-shift distribution on the reflectarray surface which generates the shaped pattern. The second stage consists of determining the length of the delay lines. aperture-coupled to the square patches, in order to achieve the phase distribution synthesized in the previous step. Two reflectarray antennas have been designed, one for vertical (V) and the other for horizontal (H) polarization. A breadboard for V-polarization has been manufactured and tested in an anechoic chamber. showing a good agreement between theoretical and measured radiation patterns. |
Hu, Wenfei; Cahill, Robert; Encinar, Jose A; Dickie, Raymond; Gamble, Harold S; Fusco, Vincent; Grant, Norman Design and Measurement of Reconfigurable Millimeter Wave Reflectarray Cells with Nematic Liquid Crystal Artículo de revista IEEE TRANSACTIONS ON ANTENNAS AND PROPAGATION, 56 (10), pp. 3112-3117, 2008, ISSN: 0018-926X. @article{Hu2008, title = {Design and Measurement of Reconfigurable Millimeter Wave Reflectarray Cells with Nematic Liquid Crystal}, author = {Wenfei Hu and Robert Cahill and Jose A Encinar and Raymond Dickie and Harold S Gamble and Vincent Fusco and Norman Grant}, doi = {10.1109/TAP.2008.929460}, issn = {0018-926X}, year = {2008}, date = {2008-10-01}, journal = {IEEE TRANSACTIONS ON ANTENNAS AND PROPAGATION}, volume = {56}, number = {10}, pages = {3112-3117}, abstract = {Numerical simulations are used to study the electromagnetic scattering front phase agile microstrip reflectarray cells which exploit the voltage controlled dielectric anisotropy property of nematic state liquid crystals (LCs). In the computer model two arrays of equal size elements constructed on a 15 mu m thick tuneable LC layer were designed to operate at center frequencies of 102 GHz and 13 GHz. Micromachining processes based on the metallization of quartz/silicon wafers and in industry compatible LCD packaging technique were employed to fabricate the grounded periodic structures. The loss and the phase of the reflected signals were measured using a quasi-optical test bench with the reflectarray inserted at the beam waist of the imaged Gaussian beam, thus eliminating sonic of the major problems associated with traditional free-space characterization at these frequencies. By applying a low frequency AC bias voltage of 10 V, a 165 degrees phase shift with a loss 4.5-6.4 dB at 102 GHz and 130 degrees phase shift with a loss variation between 4.3-7 dB at 130 GHz was obtained. The experimental results are shown to be in close agreement with the computer model.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Numerical simulations are used to study the electromagnetic scattering front phase agile microstrip reflectarray cells which exploit the voltage controlled dielectric anisotropy property of nematic state liquid crystals (LCs). In the computer model two arrays of equal size elements constructed on a 15 mu m thick tuneable LC layer were designed to operate at center frequencies of 102 GHz and 13 GHz. Micromachining processes based on the metallization of quartz/silicon wafers and in industry compatible LCD packaging technique were employed to fabricate the grounded periodic structures. The loss and the phase of the reflected signals were measured using a quasi-optical test bench with the reflectarray inserted at the beam waist of the imaged Gaussian beam, thus eliminating sonic of the major problems associated with traditional free-space characterization at these frequencies. By applying a low frequency AC bias voltage of 10 V, a 165 degrees phase shift with a loss 4.5-6.4 dB at 102 GHz and 130 degrees phase shift with a loss variation between 4.3-7 dB at 130 GHz was obtained. The experimental results are shown to be in close agreement with the computer model. |
Navarro-Tapia, M; Esteban, J; Camacho-Peñalosa, C Frequency Scanning Capabilities of a Long Slot in a Metamaterial-Based Waveguide Artículo en actas Proceedings of the 2nd International Congress on Advanced Electromagnetic Materials in Microwaves and Optics (METAMATERIALS), pp. 696-698, Pamplona (Spain), 2008, (ISBN 978-84-9769-229-8). @inproceedings{NavarroTapia2008, title = {Frequency Scanning Capabilities of a Long Slot in a Metamaterial-Based Waveguide}, author = {M Navarro-Tapia and J Esteban and C Camacho-Peñalosa}, year = {2008}, date = {2008-09-01}, booktitle = {Proceedings of the 2nd International Congress on Advanced Electromagnetic Materials in Microwaves and Optics (METAMATERIALS)}, pages = {696-698}, address = {Pamplona (Spain)}, abstract = {Frequency-scanning capabilities of continuous-type leaky-wave antennas have been usually restricted to radiation directions within the forward quadrant. With the appearance of metamaterial-based waveguides it has been possible to spread the spatial range of scanning angles to the backward quadrant, including broadside. This paper presents the improved scanning capabilities of a long-slot leaky-wave metamaterial antenna. Analytical and simulated results are in reasonable agreement. They confirm not only the frequency-scanning capabilities of such a type of antennas, but also the validity of the numerical analysis technique employed.}, note = {ISBN 978-84-9769-229-8}, keywords = {}, pubstate = {published}, tppubtype = {inproceedings} } Frequency-scanning capabilities of continuous-type leaky-wave antennas have been usually restricted to radiation directions within the forward quadrant. With the appearance of metamaterial-based waveguides it has been possible to spread the spatial range of scanning angles to the backward quadrant, including broadside. This paper presents the improved scanning capabilities of a long-slot leaky-wave metamaterial antenna. Analytical and simulated results are in reasonable agreement. They confirm not only the frequency-scanning capabilities of such a type of antennas, but also the validity of the numerical analysis technique employed. |
Page, J E; Esteban, J; Camacho-Peñalosa, C Modelling the Coupling Between Microstrip Ring-resonators and Transmission Lines by a Microwave Circuit-Based Approach Artículo en actas Proceedings of the 2nd International Congress on Advanced Electromagnetic Materials in Microwaves and Optics (METAMATERIALS), pp. 641-643, Pamplona (Spain), 2008, (ISBN 978-84-9769-229-8). @inproceedings{Page2008a, title = {Modelling the Coupling Between Microstrip Ring-resonators and Transmission Lines by a Microwave Circuit-Based Approach}, author = {J E Page and J Esteban and C Camacho-Peñalosa}, year = {2008}, date = {2008-09-01}, booktitle = {Proceedings of the 2nd International Congress on Advanced Electromagnetic Materials in Microwaves and Optics (METAMATERIALS)}, pages = {641-643}, address = {Pamplona (Spain)}, abstract = {This contribution describes a microwave circuit-based approach to obtain the equivalent circuit of microstrip ring resonators coupled to a transmission line, considering the coupling structure and the resonator structure as separate elements. The method can be applied to a wide range of resonators, and used to accurately predict the behaviour of circuits containing several resonators as well as to take advantage of existing synthesis techniques.}, note = {ISBN 978-84-9769-229-8}, keywords = {}, pubstate = {published}, tppubtype = {inproceedings} } This contribution describes a microwave circuit-based approach to obtain the equivalent circuit of microstrip ring resonators coupled to a transmission line, considering the coupling structure and the resonator structure as separate elements. The method can be applied to a wide range of resonators, and used to accurately predict the behaviour of circuits containing several resonators as well as to take advantage of existing synthesis techniques. |
de la Rubia, Valentin; Zapata, Juan; Gonzalez-de-Aza, Miguel A Finite element analysis of periodic structures without constrained meshes Artículo de revista IEEE TRANSACTIONS ON ANTENNAS AND PROPAGATION, 56 (9), pp. 3020-3028, 2008, ISSN: 0018-926X. @article{Rubia2008, title = {Finite element analysis of periodic structures without constrained meshes}, author = {Valentin de la Rubia and Juan Zapata and Miguel A Gonzalez-de-Aza}, doi = {10.1109/TAP.2008.928776}, issn = {0018-926X}, year = {2008}, date = {2008-09-01}, journal = {IEEE TRANSACTIONS ON ANTENNAS AND PROPAGATION}, volume = {56}, number = {9}, pages = {3020-3028}, abstract = {A finite element analysis is detailed of periodic structures without constrained meshes. The infinite periodic analysis domain is reduced to the unit cell analysis by means of the Floquet-Bloch decomposition, where an admittance-type matrix approach is carried out. Special emphasis is placed on the admittance-type matrix generation in such a way that the constrained meshing problem is no longer required. As a result, periodic ports are permitted in the unit cell, and the Floquet-Bloch periodic conditions are easily applied in the admittance-type matrix by means of a connection-like handling. Several infinite periodic antennas are shown to be analyzed appropriately.}, keywords = {}, pubstate = {published}, tppubtype = {article} } A finite element analysis is detailed of periodic structures without constrained meshes. The infinite periodic analysis domain is reduced to the unit cell analysis by means of the Floquet-Bloch decomposition, where an admittance-type matrix approach is carried out. Special emphasis is placed on the admittance-type matrix generation in such a way that the constrained meshing problem is no longer required. As a result, periodic ports are permitted in the unit cell, and the Floquet-Bloch periodic conditions are easily applied in the admittance-type matrix by means of a connection-like handling. Several infinite periodic antennas are shown to be analyzed appropriately. |
Corcoles, Juan; Gonzalez-de-Aza, Miguel A; Zapata, Juan Cad of stacked patch antennas through multipurpose admittance matrices from FEM and neural networks Artículo de revista MICROWAVE AND OPTICAL TECHNOLOGY LETTERS, 50 (9), pp. 2411-2416, 2008, ISSN: 0895-2477. @article{Corcoles2008, title = {Cad of stacked patch antennas through multipurpose admittance matrices from FEM and neural networks}, author = {Juan Corcoles and Miguel A Gonzalez-de-Aza and Juan Zapata}, doi = {10.1002/mop.23670}, issn = {0895-2477}, year = {2008}, date = {2008-09-01}, journal = {MICROWAVE AND OPTICAL TECHNOLOGY LETTERS}, volume = {50}, number = {9}, 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 new v 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. (C) 2008 Wiley Periodicals, Inc.}, keywords = {}, pubstate = {published}, tppubtype = {article} } 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 new v 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. (C) 2008 Wiley Periodicals, Inc. |
Martinez-Fernandez, Jose; de la Rubia, Valentin; Gil, Jose M; Zapata, Juan Frequency notched UWB planar monopole antenna optimization using a finite element method-based approach Artículo de revista IEEE TRANSACTIONS ON ANTENNAS AND PROPAGATION, 56 (9), pp. 2884-2893, 2008, ISSN: 0018-926X. @article{MartinezFernandez2008, title = {Frequency notched UWB planar monopole antenna optimization using a finite element method-based approach}, author = {Jose Martinez-Fernandez and Valentin de la Rubia and Jose M Gil and Juan Zapata}, doi = {10.1109/TAP.2008.928805}, issn = {0018-926X}, year = {2008}, date = {2008-09-01}, journal = {IEEE TRANSACTIONS ON ANTENNAS AND PROPAGATION}, volume = {56}, number = {9}, pages = {2884-2893}, keywords = {}, pubstate = {published}, tppubtype = {article} } |
Carrasco, Eduardo; Encinar, Jose A; Barba, Mariano Bandwidth improvement in large reflectarrays by using true-time delay Artículo de revista IEEE TRANSACTIONS ON ANTENNAS AND PROPAGATION, 56 (8, 2), pp. 2496-2503, 2008, ISSN: 0018-926X. @article{Carrasco2008a, title = {Bandwidth improvement in large reflectarrays by using true-time delay}, author = {Eduardo Carrasco and Jose A Encinar and Mariano Barba}, doi = {10.1109/TAP.2008.927559}, issn = {0018-926X}, year = {2008}, date = {2008-08-01}, journal = {IEEE TRANSACTIONS ON ANTENNAS AND PROPAGATION}, volume = {56}, number = {8, 2}, pages = {2496-2503}, abstract = {A significant improvement in the bandwidth of large reflectarrays is demonstrated using elements which allow true-time delay. Two identical, large reflectarrays have been designed using different phase distributions to generate a collimated beam. In the former, the phase distribution is truncated to 360 degrees as is usual in reflectarray antennas, while in the second, the true phase delay is maintained (three cycles of 360 degrees). The chosen phase-shifter elements are based on previously measured and validated patches aperture-coupled to delay lines. The radiation patterns for both reflectarrays have been computed at several frequencies and the gain is represented as a function of frequency for both cases. Bandwidth curves are presented as a function of the reflectarray size.}, keywords = {}, pubstate = {published}, tppubtype = {article} } A significant improvement in the bandwidth of large reflectarrays is demonstrated using elements which allow true-time delay. Two identical, large reflectarrays have been designed using different phase distributions to generate a collimated beam. In the former, the phase distribution is truncated to 360 degrees as is usual in reflectarray antennas, while in the second, the true phase delay is maintained (three cycles of 360 degrees). The chosen phase-shifter elements are based on previously measured and validated patches aperture-coupled to delay lines. The radiation patterns for both reflectarrays have been computed at several frequencies and the gain is represented as a function of frequency for both cases. Bandwidth curves are presented as a function of the reflectarray size. |
Page, J E; Esteban, J Time Domain Dosimetry in Planar Layered Media Artículo en actas European Electromagnetics (EUROEM), Lausanne (Switzerland), 2008. @inproceedings{Page2008b, title = {Time Domain Dosimetry in Planar Layered Media}, author = {J E Page and J Esteban}, year = {2008}, date = {2008-07-01}, booktitle = {European Electromagnetics (EUROEM)}, address = {Lausanne (Switzerland)}, abstract = {The interaction of electromagnetic fields and biological tissues (in-vitro or in-vivo) is described in terms of the fields inside the tissue. The critical points of the phenomenon are the peak values of the E and H fields and the energy transferred to the tissue, which produces a temperature growing. A lot of work has been devoted to the cases of monochromatic electromagnetic fields, and some magnitudes, as the Specific Absorption Rate, are currently used as dosimetry indicators. But for arbitrary time varying fields, and in particular for short-pulse amplitude-modulated signals, the behaviour of the phenomenon is not fully understood yet. This work presents some results concerning the interaction of a pulse modulated plane wave impinging normally on a lossy layered media. This canonical problem can be used to obtain basic information about the expected peak fields and the energy transfer process in much more complex situations.}, keywords = {}, pubstate = {published}, tppubtype = {inproceedings} } The interaction of electromagnetic fields and biological tissues (in-vitro or in-vivo) is described in terms of the fields inside the tissue. The critical points of the phenomenon are the peak values of the E and H fields and the energy transferred to the tissue, which produces a temperature growing. A lot of work has been devoted to the cases of monochromatic electromagnetic fields, and some magnitudes, as the Specific Absorption Rate, are currently used as dosimetry indicators. But for arbitrary time varying fields, and in particular for short-pulse amplitude-modulated signals, the behaviour of the phenomenon is not fully understood yet. This work presents some results concerning the interaction of a pulse modulated plane wave impinging normally on a lossy layered media. This canonical problem can be used to obtain basic information about the expected peak fields and the energy transfer process in much more complex situations. |
Ruiz-Cruz, Jorge A; Montejo-Garai, Jose R; Rebollar, Jesus M Full-wave modeling and optimization of Boifot junction ortho-mode transducers Artículo de revista INTERNATIONAL JOURNAL OF RF AND MICROWAVE COMPUTER-AIDED ENGINEERING, 18 (4), pp. 303-313, 2008, ISSN: 1096-4290. @article{RuizCruz2008, title = {Full-wave modeling and optimization of Boifot junction ortho-mode transducers}, author = {Jorge A Ruiz-Cruz and Jose R Montejo-Garai and Jesus M Rebollar}, doi = {10.1002/mmce.20287}, issn = {1096-4290}, year = {2008}, date = {2008-07-01}, journal = {INTERNATIONAL JOURNAL OF RF AND MICROWAVE COMPUTER-AIDED ENGINEERING}, volume = {18}, number = {4}, pages = {303-313}, abstract = {The full-wave design of broadband ortho-mode transducers based on the Boifot junction has two main aspects: an efficient analysis method and a design process divided into tasks with relatively low computational effort. In the analysis part, a rigorous mode-matching technique has been developed to obtain the generalized admittance matrix of the Boifot junction. The other elements of the device are also analyzed by mode-matching. With respect to the design, the proposed procedure starts with the optimization of the individual building blocks of the device. Their interaction is also taken into account in a systematic process. The analysis and design methods have been validated with other numerical methods and an experimental prototype. (C) 2008 Wiley Periodicals, Inc.}, keywords = {}, pubstate = {published}, tppubtype = {article} } The full-wave design of broadband ortho-mode transducers based on the Boifot junction has two main aspects: an efficient analysis method and a design process divided into tasks with relatively low computational effort. In the analysis part, a rigorous mode-matching technique has been developed to obtain the generalized admittance matrix of the Boifot junction. The other elements of the device are also analyzed by mode-matching. With respect to the design, the proposed procedure starts with the optimization of the individual building blocks of the device. Their interaction is also taken into account in a systematic process. The analysis and design methods have been validated with other numerical methods and an experimental prototype. (C) 2008 Wiley Periodicals, Inc. |
Arrebola, Manuel; Encinar, Jose A; Barba, Mariano Multifed printed reflectarray with three simultaneous shaped beams for LMDS central station antenna Artículo de revista IEEE TRANSACTIONS ON ANTENNAS AND PROPAGATION, 56 (6), pp. 1518-1527, 2008, ISSN: 0018-926X. @article{Arrebola2008a, title = {Multifed printed reflectarray with three simultaneous shaped beams for LMDS central station antenna}, author = {Manuel Arrebola and Jose A Encinar and Mariano Barba}, doi = {10.1109/TAP.2008.923360}, issn = {0018-926X}, year = {2008}, date = {2008-06-01}, journal = {IEEE TRANSACTIONS ON ANTENNAS AND PROPAGATION}, volume = {56}, number = {6}, pages = {1518-1527}, abstract = {A two-layer reflectarray is proposed as a central station antenna for a local multipoint distribution system (LMDS) in the 24.5-26.5 GHz band. The antenna produces three independent beams in an alternate linear polarization that are shaped both in azimuth (sectored) and in elevation (squared cosecant). The design process is divided into several stages. First, the positions of the three feeds are established as well as the antenna geometry to produce the three beams in the required directions. Second, the phase distribution on the reflectarray surface, which produces the required beam shaping, is synthesized. Third, the sizes of the printed stacked patches are adjusted so that the phase-shift introduced by them matches the synthesized phase distribution. Finally, the radiation patterns are computed for the central and lateral beams, showing a shaping close to the requirements. A breadboard has been manufactured and measured in an anechoic chamber, showing a good behavior, which validates the designing methodology.}, keywords = {}, pubstate = {published}, tppubtype = {article} } A two-layer reflectarray is proposed as a central station antenna for a local multipoint distribution system (LMDS) in the 24.5-26.5 GHz band. The antenna produces three independent beams in an alternate linear polarization that are shaped both in azimuth (sectored) and in elevation (squared cosecant). The design process is divided into several stages. First, the positions of the three feeds are established as well as the antenna geometry to produce the three beams in the required directions. Second, the phase distribution on the reflectarray surface, which produces the required beam shaping, is synthesized. Third, the sizes of the printed stacked patches are adjusted so that the phase-shift introduced by them matches the synthesized phase distribution. Finally, the radiation patterns are computed for the central and lateral beams, showing a shaping close to the requirements. A breadboard has been manufactured and measured in an anechoic chamber, showing a good behavior, which validates the designing methodology. |
Martinez-Fernandez, Jose; Gil, Jose M; Zapata, Juan Optimized profile planar UWB monopole antenna for optimal adaptation Artículo en actas 2008 IEEE ANTENNAS AND PROPAGATION SOCIETY INTERNATIONAL SYMPOSIUM, VOLS 1-9, pp. 823-826, IEEE 2008, ISSN: 1522-3965, (IEEE Antennas-and-Propagation-Society International Symposium, San Diego, CA, JUL 05-11, 2008). @inproceedings{MartinezFernandez2008a, title = {Optimized profile planar UWB monopole antenna for optimal adaptation}, author = {Jose Martinez-Fernandez and Jose M Gil and Juan Zapata}, issn = {1522-3965}, year = {2008}, date = {2008-01-01}, booktitle = {2008 IEEE ANTENNAS AND PROPAGATION SOCIETY INTERNATIONAL SYMPOSIUM, VOLS 1-9}, pages = {823-826}, organization = {IEEE}, series = {IEEE Antennas and Propagation Society International Symposium}, note = {IEEE Antennas-and-Propagation-Society International Symposium, San Diego, CA, JUL 05-11, 2008}, keywords = {}, pubstate = {published}, tppubtype = {inproceedings} } |
Martinez-Fernandez, José; Gil, Jose M; Zapata, Juan Optimization of Frequency Notched UWB Monopole Antennas by means of Genetic Algorithms with Multipurpose Admitance Matrix Analysis Approach Artículo en actas San Diego, USA, 2008. @inproceedings{MartinezFernandez2008c, title = {Optimization of Frequency Notched UWB Monopole Antennas by means of Genetic Algorithms with Multipurpose Admitance Matrix Analysis Approach}, author = {José Martinez-Fernandez and Jose M Gil and Juan Zapata}, year = {2008}, date = {2008-01-01}, address = {San Diego, USA}, keywords = {}, pubstate = {published}, tppubtype = {inproceedings} } |
Gil, Jose M Study of Axisymmetric dielectric resonators in MIC Environments based on Finite Elements Artículo en actas San Diego, USA, 2008. @inproceedings{Gil2008, title = {Study of Axisymmetric dielectric resonators in MIC Environments based on Finite Elements}, author = {Jose M Gil}, year = {2008}, date = {2008-01-01}, address = {San Diego, USA}, keywords = {}, pubstate = {published}, tppubtype = {inproceedings} } |
Martínez-Fernández, José; Gil, Jose M; Zapata, Juan Optimized Profile Monopole Antennas through Finite Elements for UWB Applications Artículo en actas Bonn, Germany. Conferencia Invitada, 2008. @inproceedings{MartinezFernandez2008d, title = {Optimized Profile Monopole Antennas through Finite Elements for UWB Applications}, author = {José Martínez-Fernández and Jose M Gil and Juan Zapata}, year = {2008}, date = {2008-01-01}, address = {Bonn, Germany. Conferencia Invitada}, keywords = {}, pubstate = {published}, tppubtype = {inproceedings} } |
Martínez-Fernández, José; Gil, Jose M; Zapata, Juan Optimized profile dielectric coating in UWB monopole antenna for radiation pattern gain stability and optimal adaptation Artículo en actas Noordwijk. Holland, 2008. @inproceedings{MartinezFernandez2008b, title = {Optimized profile dielectric coating in UWB monopole antenna for radiation pattern gain stability and optimal adaptation}, author = {José Martínez-Fernández and Jose M Gil and Juan Zapata}, year = {2008}, date = {2008-01-01}, address = {Noordwijk. Holland}, keywords = {}, pubstate = {published}, tppubtype = {inproceedings} } |
Huang, John; Encinar, Jose A Reflectarray Antennas Capítulo de libro REFLECTARRAY ANTENNAS, pp. 1-216, 2008, ISBN: 978-0-470-17877-5. @inbook{Huang2008, title = {Reflectarray Antennas}, author = {John Huang and Jose A Encinar}, isbn = {978-0-470-17877-5}, year = {2008}, date = {2008-01-01}, booktitle = {REFLECTARRAY ANTENNAS}, pages = {1-216}, keywords = {}, pubstate = {published}, tppubtype = {inbook} } |
Huang, John; Encinar, Jose A Introduction to Reflectarray Antenna Capítulo de libro REFLECTARRAY ANTENNAS, pp. 1-7, 2008, ISBN: 978-0-470-17877-5. @inbook{Huang2008a, title = {Introduction to Reflectarray Antenna}, author = {John Huang and Jose A Encinar}, isbn = {978-0-470-17877-5}, year = {2008}, date = {2008-01-01}, booktitle = {REFLECTARRAY ANTENNAS}, pages = {1-7}, keywords = {}, pubstate = {published}, tppubtype = {inbook} } |
Huang, John; Encinar, Jose A Development History Capítulo de libro REFLECTARRAY ANTENNAS, pp. 9-26, 2008, ISBN: 978-0-470-17877-5; 978-0-470-08491-5. @inbook{Huang2008b, title = {Development History}, author = {John Huang and Jose A Encinar}, isbn = {978-0-470-17877-5; 978-0-470-08491-5}, year = {2008}, date = {2008-01-01}, booktitle = {REFLECTARRAY ANTENNAS}, pages = {9-26}, keywords = {}, pubstate = {published}, tppubtype = {inbook} } |
Huang, John; Encinar, Jose A Antenna Analysis Techniques Capítulo de libro REFLECTARRAY ANTENNAS, pp. 27-78, 2008, ISBN: 978-0-470-17877-5; 978-0-470-08491-5. @inbook{Huang2008c, title = {Antenna Analysis Techniques}, author = {John Huang and Jose A Encinar}, isbn = {978-0-470-17877-5; 978-0-470-08491-5}, year = {2008}, date = {2008-01-01}, booktitle = {REFLECTARRAY ANTENNAS}, pages = {27-78}, keywords = {}, pubstate = {published}, tppubtype = {inbook} } |
Huang, John; Encinar, Jose A Practical Design Approach Capítulo de libro REFLECTARRAY ANTENNAS, pp. 79-92, 2008, ISBN: 978-0-470-17877-5. @inbook{Huang2008d, title = {Practical Design Approach}, author = {John Huang and Jose A Encinar}, isbn = {978-0-470-17877-5}, year = {2008}, date = {2008-01-01}, booktitle = {REFLECTARRAY ANTENNAS}, pages = {79-92}, keywords = {}, pubstate = {published}, tppubtype = {inbook} } |
Huang, John; Encinar, Jose A Broadband Techniques Capítulo de libro REFLECTARRAY ANTENNAS, pp. 93-118, 2008, ISBN: 978-0-470-17877-5. @inbook{Huang2008e, title = {Broadband Techniques}, author = {John Huang and Jose A Encinar}, isbn = {978-0-470-17877-5}, year = {2008}, date = {2008-01-01}, booktitle = {REFLECTARRAY ANTENNAS}, pages = {93-118}, keywords = {}, pubstate = {published}, tppubtype = {inbook} } |
Huang, John; Encinar, Jose A Dual-Band Reflectarray Capítulo de libro REFLECTARRAY ANTENNAS, pp. 119-135, 2008, ISBN: 978-0-470-17877-5. @inbook{Huang2008f, title = {Dual-Band Reflectarray}, author = {John Huang and Jose A Encinar}, isbn = {978-0-470-17877-5}, year = {2008}, date = {2008-01-01}, booktitle = {REFLECTARRAY ANTENNAS}, pages = {119-135}, keywords = {}, pubstate = {published}, tppubtype = {inbook} } |
Huang, John; Encinar, Jose A Recent and Future Applications Capítulo de libro REFLECTARRAY ANTENNAS, pp. 137-205, 2008, ISBN: 978-0-470-17877-5; 978-0-470-08491-5. @inbook{Huang2008g, title = {Recent and Future Applications}, author = {John Huang and Jose A Encinar}, isbn = {978-0-470-17877-5; 978-0-470-08491-5}, year = {2008}, date = {2008-01-01}, booktitle = {REFLECTARRAY ANTENNAS}, pages = {137-205}, keywords = {}, pubstate = {published}, tppubtype = {inbook} } |
Ruiz-Cruz, Jorge A; Zhang, Yunchi; Montejo-Garai, Jose R; Rebollar, Jesus M; Zaki, Kawthar A Longitudinal Dual-Mode Filters in Rectangular Waveguide Artículo en actas 2008 IEEE MTT-S INTERNATIONAL MICROWAVE SYMPOSIUM DIGEST, VOLS 1-4, pp. 631-634, IEEE 2008, ISSN: 0149-645X, (2008 IEEE MTT-S International Microwave Symposium Digest, Atlanta, GA, JUN 15-20, 2008). @inproceedings{RuizCruz2008a, title = {Longitudinal Dual-Mode Filters in Rectangular Waveguide}, author = {Jorge A Ruiz-Cruz and Yunchi Zhang and Jose R Montejo-Garai and Jesus M Rebollar and Kawthar A Zaki}, doi = {10.1109/MWSYM.2008.4632911}, issn = {0149-645X}, year = {2008}, date = {2008-01-01}, booktitle = {2008 IEEE MTT-S INTERNATIONAL MICROWAVE SYMPOSIUM DIGEST, VOLS 1-4}, pages = {631-634}, organization = {IEEE}, series = {IEEE MTT-S International Microwave Symposium}, abstract = {Dual-Mode filters are used in applications where low mass and volume are required. In this paper, the Computer Aided Design of a new rectangular waveguide filter structure is proposed for achieving the dual-mode operation. It preserves the longitudinal inline topology used in the classical circular waveguide configuration, which can provide quasi-elliptic function responses. However, it has no coupling or tuning screws and it is exclusively made up of sections of aligned rectangular waveguides. This leads to a very efficient full-wave analysis based on the Mode-Matching method. The proposed CAD is illustrated with a four order prototype, whose results are compared with other numerical technique.}, note = {2008 IEEE MTT-S International Microwave Symposium Digest, Atlanta, GA, JUN 15-20, 2008}, keywords = {}, pubstate = {published}, tppubtype = {inproceedings} } Dual-Mode filters are used in applications where low mass and volume are required. In this paper, the Computer Aided Design of a new rectangular waveguide filter structure is proposed for achieving the dual-mode operation. It preserves the longitudinal inline topology used in the classical circular waveguide configuration, which can provide quasi-elliptic function responses. However, it has no coupling or tuning screws and it is exclusively made up of sections of aligned rectangular waveguides. This leads to a very efficient full-wave analysis based on the Mode-Matching method. The proposed CAD is illustrated with a four order prototype, whose results are compared with other numerical technique. |
Ruiz-Cruz, Jorge A; Montejo-Garai, Jose R; Rebollar, J M; Sobrino, S COMPACT FULL KU-BAND TRIPLEXER WITH IMPROVED E-PLANE POWER DIVIDER Artículo de revista PROGRESS IN ELECTROMAGNETICS RESEARCH-PIER, 86 , pp. 39-51, 2008. @article{RuizCruz2008b, title = {COMPACT FULL KU-BAND TRIPLEXER WITH IMPROVED E-PLANE POWER DIVIDER}, author = {Jorge A Ruiz-Cruz and Jose R Montejo-Garai and J M Rebollar and S Sobrino}, doi = {10.2528/PIER08082803}, year = {2008}, date = {2008-01-01}, journal = {PROGRESS IN ELECTROMAGNETICS RESEARCH-PIER}, volume = {86}, pages = {39-51}, abstract = {An improved E-plane power divider for compact waveguide triplexers with large separation between channels is presented. The configuration of the divider aims to exploit the different behavior of the device for frequency bands with large separation, leading to a very asymmetric E-plane junction. H-plane filters with inductive windows are used for each channel, in order to obtain reduced insertion losses and lower sensitivity than in metal-insert E-plane filters. The resultant triplexer configuration is very compact, and its design is analyzed and optimized by Mode-Matching. The experimental results of a full Ku-band prototype for communications satellite systems show a very good agreement with the expected simulated response.}, keywords = {}, pubstate = {published}, tppubtype = {article} } An improved E-plane power divider for compact waveguide triplexers with large separation between channels is presented. The configuration of the divider aims to exploit the different behavior of the device for frequency bands with large separation, leading to a very asymmetric E-plane junction. H-plane filters with inductive windows are used for each channel, in order to obtain reduced insertion losses and lower sensitivity than in metal-insert E-plane filters. The resultant triplexer configuration is very compact, and its design is analyzed and optimized by Mode-Matching. The experimental results of a full Ku-band prototype for communications satellite systems show a very good agreement with the expected simulated response. |
2007 |
Page, J E; Esteban, J; Camacho-Peñalosa, C On the Equivalent Circuits of Microstripline and Slotline Pendry-like Resonators Coupled to Microstrip Lines Artículo en actas Proceedings of the 11th International Symposium on Microwave and Optical Technology (ISMOT), pp. 155-158, Villa Mondragone, Monte Porzio Catone (Italy), 2007, (ISBN 978-88-548-1476-9). @inproceedings{Page2007b, title = {On the Equivalent Circuits of Microstripline and Slotline Pendry-like Resonators Coupled to Microstrip Lines}, author = {J E Page and J Esteban and C Camacho-Peñalosa}, year = {2007}, date = {2007-12-01}, booktitle = {Proceedings of the 11th International Symposium on Microwave and Optical Technology (ISMOT)}, pages = {155-158}, address = {Villa Mondragone, Monte Porzio Catone (Italy)}, abstract = {Narrowband equivalent circuits of coupled-split-ring-resonators including the effects of the coupling of the resonator to a microstrip line are presented. The results prove that microstrip resonators act as parallel resonators in series with the main line while slotline resonators acts as series resonators in parallel with the main line. These results are fundamental to stablish the design procedures of composite right-left handed structures using this kind of resonators.}, note = {ISBN 978-88-548-1476-9}, keywords = {}, pubstate = {published}, tppubtype = {inproceedings} } Narrowband equivalent circuits of coupled-split-ring-resonators including the effects of the coupling of the resonator to a microstrip line are presented. The results prove that microstrip resonators act as parallel resonators in series with the main line while slotline resonators acts as series resonators in parallel with the main line. These results are fundamental to stablish the design procedures of composite right-left handed structures using this kind of resonators. |
Huang, John; Encinar, Jose A Reflectarray Antennas Libro John Wiley & Sons, 2007, ISBN: 047008491X. @book{Huang2007, title = {Reflectarray Antennas}, author = {John Huang and Jose A Encinar}, url = {https://www.ebook.de/de/product/6560104/huang_encinar_john_huang_reflectarray_antennas.html}, isbn = {047008491X}, year = {2007}, date = {2007-10-16}, publisher = {John Wiley & Sons}, keywords = {}, pubstate = {published}, tppubtype = {book} } |
Page, J E; Márquez-Segura, E; Casares-Miranda, F P; Esteban, J; Otero, P; Camacho-Peñalosa, C Exact Analysis of the Wire-Bonded Multiconductor Transmission Line Artículo de revista IEEE Transactions on Microwave Theory and Techniques, 55 (8), pp. 1585-1592, 2007, ISSN: 0018-9480. @article{Page2007a, title = {Exact Analysis of the Wire-Bonded Multiconductor Transmission Line}, author = {J E Page and E Márquez-Segura and F P Casares-Miranda and J Esteban and P Otero and C Camacho-Peñalosa}, doi = {10.1109/TMTT.2007.902084}, issn = {0018-9480}, year = {2007}, date = {2007-08-01}, journal = {IEEE Transactions on Microwave Theory and Techniques}, volume = {55}, number = {8}, pages = {1585-1592}, abstract = {In this paper, the exact model of a multiconductor transmission line with bonding wires is presented. The model is based on the multiport admittance matrix, and is valid for any number of conductors in the structure. The model shows how to compute the two-port admittance matrix of the wire-bonded structure with direct application to the wire-bonded interdigital capacitor. The model has been validated by means of method-of-moments-based numerical simulation and by experimental work.}, keywords = {}, pubstate = {published}, tppubtype = {article} } In this paper, the exact model of a multiconductor transmission line with bonding wires is presented. The model is based on the multiport admittance matrix, and is valid for any number of conductors in the structure. The model shows how to compute the two-port admittance matrix of the wire-bonded structure with direct application to the wire-bonded interdigital capacitor. The model has been validated by means of method-of-moments-based numerical simulation and by experimental work. |
Hu, Wenfei; Ismail, M Y; Cahill, Robert; Encinar, Jose A; Fusco, Vincent; Gamble, Harold S; Linton, D; Dickie, Raymond; Grant, Norman; Rea, S P Liquid-crystal-based reflectarray antenna with electronically switchable monopulse patterns Artículo de revista ELECTRONICS LETTERS, 43 (14), pp. 744-745, 2007, ISSN: 0013-5194. @article{Hu2007, title = {Liquid-crystal-based reflectarray antenna with electronically switchable monopulse patterns}, author = {Wenfei Hu and M Y Ismail and Robert Cahill and Jose A Encinar and Vincent Fusco and Harold S Gamble and D Linton and Raymond Dickie and Norman Grant and S P Rea}, doi = {10.1049/el:20071098}, issn = {0013-5194}, year = {2007}, date = {2007-07-01}, journal = {ELECTRONICS LETTERS}, volume = {43}, number = {14}, pages = {744-745}, abstract = {A printed rcflectarray antenna, which generates a beam that can be electronically switched from a sum to a difference radiation pattern, is presented. This is achieved by applying a bias voltage of 20 V to one-half of the aperture, which is constructed above a 500 mu m cavity containing liquid crystals. Simulated results are shown to be in good agreement with measurements at X-band.}, keywords = {}, pubstate = {published}, tppubtype = {article} } A printed rcflectarray antenna, which generates a beam that can be electronically switched from a sum to a difference radiation pattern, is presented. This is achieved by applying a bias voltage of 20 V to one-half of the aperture, which is constructed above a 500 mu m cavity containing liquid crystals. Simulated results are shown to be in good agreement with measurements at X-band. |
Martinez-Fernandez, Jose; Gil, Jose M; Zapata, Juan Ultrawideband optimized profile monopole antenna by means of simulated annealing algorithm and the finite element method Artículo de revista IEEE TRANSACTIONS ON ANTENNAS AND PROPAGATION, 55 (6, 2), pp. 1826-1832, 2007, ISSN: 0018-926X. @article{MartinezFernandez2007, title = {Ultrawideband optimized profile monopole antenna by means of simulated annealing algorithm and the finite element method}, author = {Jose Martinez-Fernandez and Jose M Gil and Juan Zapata}, doi = {10.1109/TAP.2007.898593}, issn = {0018-926X}, year = {2007}, date = {2007-06-01}, journal = {IEEE TRANSACTIONS ON ANTENNAS AND PROPAGATION}, volume = {55}, number = {6, 2}, pages = {1826-1832}, keywords = {}, pubstate = {published}, tppubtype = {article} } |
Gil, Jose M; Webb, Jon P On the two dimension applications of high-order vector finite elements to the study of electromagnetic resonance Artículo de revista IET MICROWAVES ANTENNAS & PROPAGATION, 1 (2), pp. 306-313, 2007, ISSN: 1751-8725. @article{Gil2007, title = {On the two dimension applications of high-order vector finite elements to the study of electromagnetic resonance}, author = {Jose M Gil and Jon P Webb}, doi = {10.1049/iet-map:20060159}, issn = {1751-8725}, year = {2007}, date = {2007-04-01}, journal = {IET MICROWAVES ANTENNAS & PROPAGATION}, volume = {1}, number = {2}, pages = {306-313}, keywords = {}, pubstate = {published}, tppubtype = {article} } |
Carrasco, Eduardo; Barba, Mariano; Encinar, Jose A Reflectarray element based on aperture-coupled patches with slots and lines of variable length Artículo de revista IEEE TRANSACTIONS ON ANTENNAS AND PROPAGATION, 55 (3, 2), pp. 820-825, 2007, ISSN: 0018-926X. @article{Carrasco2007a, title = {Reflectarray element based on aperture-coupled patches with slots and lines of variable length}, author = {Eduardo Carrasco and Mariano Barba and Jose A Encinar}, doi = {10.1109/TAP.2007.891863}, issn = {0018-926X}, year = {2007}, date = {2007-03-01}, journal = {IEEE TRANSACTIONS ON ANTENNAS AND PROPAGATION}, volume = {55}, number = {3, 2}, pages = {820-825}, abstract = {A phase-shifter element for printed reflectarrays with more than 4 cycles of phase delay is presented in this work. The proposed reflectarray element allows very linear phase curves and is based on the combination of two previously studied and demonstrated concepts: variable length slots on a ground plane and patches coupled through a slot to variable length lines. In the former, the slots act as inductive loading on the patches depending on their length. With the second concept, the effect of nonconstant path delay is alleviated by the introduction of true-time delay (TTD) lines. The mixed effect allows a much larger range of phase delay to be reached and at the same time to improve the linearity of the phase delay behavior. Two ways of increasing the phase delay range are shown: the increase in length using U-shaped delay lines and the use of high permittivity substrates.}, keywords = {}, pubstate = {published}, tppubtype = {article} } A phase-shifter element for printed reflectarrays with more than 4 cycles of phase delay is presented in this work. The proposed reflectarray element allows very linear phase curves and is based on the combination of two previously studied and demonstrated concepts: variable length slots on a ground plane and patches coupled through a slot to variable length lines. In the former, the slots act as inductive loading on the patches depending on their length. With the second concept, the effect of nonconstant path delay is alleviated by the introduction of true-time delay (TTD) lines. The mixed effect allows a much larger range of phase delay to be reached and at the same time to improve the linearity of the phase delay behavior. Two ways of increasing the phase delay range are shown: the increase in length using U-shaped delay lines and the use of high permittivity substrates. |
Gil, Jose M Analysis of cylindrical and spherical dielectric resonators in cavities by means of finite elements Artículo en actas {Bonefacic, D} (Ed.): ICECOM 2007: 19TH INTERNATIONAL CONFERENCE ON APPLIED ELECTROMAGNETICS AND COMMUNICATIONS, CONFERENCE PROCEEDINGS, pp. 279-282, 2007, ISBN: 978-953-6037-50-6, (19th International Conference on Applied Electromagnetics and Communications, Dubrovnik, CROATIA, SEP 24-26, 2007). @inproceedings{Gil2007a, title = {Analysis of cylindrical and spherical dielectric resonators in cavities by means of finite elements}, author = {Jose M Gil}, editor = {D} {Bonefacic}, isbn = {978-953-6037-50-6}, year = {2007}, date = {2007-01-01}, booktitle = {ICECOM 2007: 19TH INTERNATIONAL CONFERENCE ON APPLIED ELECTROMAGNETICS AND COMMUNICATIONS, CONFERENCE PROCEEDINGS}, pages = {279-282}, note = {19th International Conference on Applied Electromagnetics and Communications, Dubrovnik, CROATIA, SEP 24-26, 2007}, keywords = {}, pubstate = {published}, tppubtype = {inproceedings} } |
Martinez-Fernandez, Jose; Gil, Jose M; Zapata, Juan Optimization of the Profile of a Planar Ultra Wide Band Monopole Antenna in Order to Minimize Return Losses Artículo en actas pp. 1–5, IET, Edinburgh, 2007, ISSN: 0537-9989. @inproceedings{MartinezFernandez2007a, title = {Optimization of the Profile of a Planar Ultra Wide Band Monopole Antenna in Order to Minimize Return Losses}, author = {Jose Martinez-Fernandez and Jose M Gil and Juan Zapata}, doi = {10.1049/ic.2007.1012}, issn = {0537-9989}, year = {2007}, date = {2007-01-01}, pages = {1--5}, publisher = {IET}, address = {Edinburgh}, abstract = {In this paper, a planar ultra wide band antenna designed to minimize return losses is presented. Low return losses over an extremely broad bandwidth are obtained performing a global optimization, implemented using the simulated annealing algorithm, over the profile of a planar monopole. To perform the required analysis in each optimization step, a versatile and fast tool was required. The Finite Element method along with the SFELP formulation was used to try to meet this criteria for the analysis tool. As a result, simulations showed that return losses of less than 14dB have been achieved in the whole frequency band. Simulations were performed using an infinite ground plane to reduce computation effort and therefore optimization time. To validate the method, a prototype was built with the obtained data. Return losses of less than 13dB were obtained in the whole band using a finite ground plane of near λ in the low frequencies. Simulation results with the infinite ground plane show an excellent agreement with measurements.}, keywords = {}, pubstate = {published}, tppubtype = {inproceedings} } In this paper, a planar ultra wide band antenna designed to minimize return losses is presented. Low return losses over an extremely broad bandwidth are obtained performing a global optimization, implemented using the simulated annealing algorithm, over the profile of a planar monopole. To perform the required analysis in each optimization step, a versatile and fast tool was required. The Finite Element method along with the SFELP formulation was used to try to meet this criteria for the analysis tool. As a result, simulations showed that return losses of less than 14dB have been achieved in the whole frequency band. Simulations were performed using an infinite ground plane to reduce computation effort and therefore optimization time. To validate the method, a prototype was built with the obtained data. Return losses of less than 13dB were obtained in the whole band using a finite ground plane of near λ in the low frequencies. Simulation results with the infinite ground plane show an excellent agreement with measurements. |
Gil, Jose M; Webb, Jon P Hybrid Vector-Scalar Finite Elements for Curved-Triangle Meshes Applied to the Study of Electromagnetic Resonances Artículo en actas pp. 1–4, IET, Edinburgh, 2007, ISSN: 0537-9989. @inproceedings{Gil2007b, title = {Hybrid Vector-Scalar Finite Elements for Curved-Triangle Meshes Applied to the Study of Electromagnetic Resonances}, author = {Jose M Gil and Jon P Webb}, doi = {10.1049/ic.2007.1200}, issn = {0537-9989}, year = {2007}, date = {2007-01-01}, pages = {1--4}, publisher = {IET}, address = {Edinburgh}, abstract = {High order vector-scalar finite elements for curved-triangle meshes are developed. These elements are applied to problems in which the variation of field along one coordinate is known. The field component along this coordinate is modeled with polynomials of degree q. The transverse component is modelled with 2-D vector edge elements containing all irrotational functions up to polynomial degree m. Only when q=m+ spurious modes are avoided. The performance of these elements to order 4 is explored by applying them to some structures containing sharp edges and/or curved boundaries.}, keywords = {}, pubstate = {published}, tppubtype = {inproceedings} } High order vector-scalar finite elements for curved-triangle meshes are developed. These elements are applied to problems in which the variation of field along one coordinate is known. The field component along this coordinate is modeled with polynomials of degree q. The transverse component is modelled with 2-D vector edge elements containing all irrotational functions up to polynomial degree m. Only when q=m+ spurious modes are avoided. The performance of these elements to order 4 is explored by applying them to some structures containing sharp edges and/or curved boundaries. |
Encinar, Jose A; Arrebola, Manuel Reduction of cross-polarization in contoured beam reflectarrays using a three-layer configuration Artículo en actas 2007 IEEE ANTENNAS AND PROPAGATION SOCIETY INTERNATIONAL SYMPOSIUM, VOLS 1-12, pp. 4833-4836, IEEE; Antennas & Propagat Soc 2007, ISSN: 1522-3965, (IEEE Antennas-and-Propagation-Society International Symposium, Honolulu, HI, JUN 09-15, 2007). @inproceedings{Encinar2007, title = {Reduction of cross-polarization in contoured beam reflectarrays using a three-layer configuration}, author = {Jose A Encinar and Manuel Arrebola}, issn = {1522-3965}, year = {2007}, date = {2007-01-01}, booktitle = {2007 IEEE ANTENNAS AND PROPAGATION SOCIETY INTERNATIONAL SYMPOSIUM, VOLS 1-12}, pages = {4833-4836}, organization = {IEEE; Antennas & Propagat Soc}, series = {IEEE Antennas and Propagation Society International Symposium}, note = {IEEE Antennas-and-Propagation-Society International Symposium, Honolulu, HI, JUN 09-15, 2007}, keywords = {}, pubstate = {published}, tppubtype = {inproceedings} } |
Bialkowski, Marek E; Encinar, Jose A; Zornoza, JA; Tsai, F C -E Printed Reflectarray Antennas Capítulo de libro {Waterhouse, R} (Ed.): PRINTED ANTENNAS FOR WIRELESS COMMUNICATIONS, pp. 299-330, 2007, ISBN: 978-0-470-51224-1. @inbook{Bialkowski2007, title = {Printed Reflectarray Antennas}, author = {Marek E Bialkowski and Jose A Encinar and JA Zornoza and F C -E Tsai}, editor = {R} {Waterhouse}, isbn = {978-0-470-51224-1}, year = {2007}, date = {2007-01-01}, booktitle = {PRINTED ANTENNAS FOR WIRELESS COMMUNICATIONS}, pages = {299-330}, keywords = {}, pubstate = {published}, tppubtype = {inbook} } |
Encinar, Jose A; Arrebola, Manuel; Toso, Giovanni A Parabolic Reflectarray for a Bandwidth Improved Contoured Beam Coverage Artículo en actas pp. 1–5, IET, Edinburgh, 2007, ISSN: 0537-9989. @inproceedings{Encinar2007a, title = {A Parabolic Reflectarray for a Bandwidth Improved Contoured Beam Coverage}, author = {Jose A Encinar and Manuel Arrebola and Giovanni Toso}, doi = {10.1049/ic.2007.1045}, issn = {0537-9989}, year = {2007}, date = {2007-01-01}, pages = {1--5}, publisher = {IET}, address = {Edinburgh}, abstract = {A two-layer reflectarray made of varying-sized patches on a parabolic surface is proposed in this paper to enlarge the bandwidth for shaped-beam antennas in telecommunication missions. The beam is focused by the parabolic surface, while the phasing on the reflectarray is used to generate the required contoured beam. A technique for the analysis and design of the parabolic configuration is presented, in which the dimensions of the patches are optimised to produce the required phase-shift, by iteratively using an analysis routine based on the method of moments (MoM) assuming local periodicity. The proposed technique has been used to design a 1.5-metre reflectarray for a South American coverage. The results show a significant improvement in bandwidth with respect to a flat reflectarray, at the cost of a higher cross-polar radiation produced by the parabolic surface.}, keywords = {}, pubstate = {published}, tppubtype = {inproceedings} } A two-layer reflectarray made of varying-sized patches on a parabolic surface is proposed in this paper to enlarge the bandwidth for shaped-beam antennas in telecommunication missions. The beam is focused by the parabolic surface, while the phasing on the reflectarray is used to generate the required contoured beam. A technique for the analysis and design of the parabolic configuration is presented, in which the dimensions of the patches are optimised to produce the required phase-shift, by iteratively using an analysis routine based on the method of moments (MoM) assuming local periodicity. The proposed technique has been used to design a 1.5-metre reflectarray for a South American coverage. The results show a significant improvement in bandwidth with respect to a flat reflectarray, at the cost of a higher cross-polar radiation produced by the parabolic surface. |
Encinar, Jose A; Arrebola, Manuel; Toso, Giovanni Design of a Tx/Rx Reflectarray Antenna for Space Applications Artículo en actas pp. 1–5, IET, Edinburgh, 2007, ISSN: 0537-9989. @inproceedings{Encinar2007b, title = {Design of a Tx/Rx Reflectarray Antenna for Space Applications}, author = {Jose A Encinar and Manuel Arrebola and Giovanni Toso}, doi = {10.1049/ic.2007.0938}, issn = {0537-9989}, year = {2007}, date = {2007-01-01}, pages = {1--5}, publisher = {IET}, address = {Edinburgh}, abstract = {A technique is presented for the design of three-layer reflectarrays for contoured beam antennas operating in two frequency bands. The technique has been applied to design a 1-m reflectarray for a South American coverage in Tx/Rx frequency bands. The technique is based on the optimisation of the patch dimensions in three layers of varying-sized patches in order to fulfil the requirements of the coverage in both Tx and Rx bands for dual linear polarisation. The results show that the gain requirements are fairly well accomplished in the whole coverage for both Tx and Rx bands. The cross-polar discrimination is better than 30 dB in most part of the coverage.}, keywords = {}, pubstate = {published}, tppubtype = {inproceedings} } A technique is presented for the design of three-layer reflectarrays for contoured beam antennas operating in two frequency bands. The technique has been applied to design a 1-m reflectarray for a South American coverage in Tx/Rx frequency bands. The technique is based on the optimisation of the patch dimensions in three layers of varying-sized patches in order to fulfil the requirements of the coverage in both Tx and Rx bands for dual linear polarisation. The results show that the gain requirements are fairly well accomplished in the whole coverage for both Tx and Rx bands. The cross-polar discrimination is better than 30 dB in most part of the coverage. |
Ruiz-Cruz, Jorge A; Montejo-Garai, Jose R; Rebollar, Jesus M; Daganzo, Ana I; Hidalgo-Carpintero, Isidro Design of Riblet-type couplers for Ka band applications Artículo en actas 2007 IEEE ANTENNAS AND PROPAGATION SOCIETY INTERNATIONAL SYMPOSIUM, VOLS 1-12, pp. 4276-4279, IEEE; Antennas & Propagat Soc 2007, ISSN: 1522-3965, (IEEE Antennas-and-Propagation-Society International Symposium, Honolulu, HI, JUN 09-15, 2007). @inproceedings{RuizCruz2007, title = {Design of Riblet-type couplers for Ka band applications}, author = {Jorge A Ruiz-Cruz and Jose R Montejo-Garai and Jesus M Rebollar and Ana I Daganzo and Isidro Hidalgo-Carpintero}, doi = {10.1109/APS.2007.4396486}, issn = {1522-3965}, year = {2007}, date = {2007-01-01}, booktitle = {2007 IEEE ANTENNAS AND PROPAGATION SOCIETY INTERNATIONAL SYMPOSIUM, VOLS 1-12}, pages = {4276-4279}, organization = {IEEE; Antennas & Propagat Soc}, series = {IEEE Antennas and Propagation Society International Symposium}, abstract = {The full-wave modeling and design of short-slot Riblet waveguide couplers are addressed in this contribution. These types of directional couplers are commonly used by their compact size in comparison with other waveguide configurations. The main features of the Riblet coupler are discussed and its modeling with different input/output excitations is described. Two different designs are shown, with either rectangular waveguide input/output ports or coaxial interfaces. The expected simulated results of two manufactured prototypes operating at 19 GHz are compared with their experimental measurements.}, note = {IEEE Antennas-and-Propagation-Society International Symposium, Honolulu, HI, JUN 09-15, 2007}, keywords = {}, pubstate = {published}, tppubtype = {inproceedings} } The full-wave modeling and design of short-slot Riblet waveguide couplers are addressed in this contribution. These types of directional couplers are commonly used by their compact size in comparison with other waveguide configurations. The main features of the Riblet coupler are discussed and its modeling with different input/output excitations is described. Two different designs are shown, with either rectangular waveguide input/output ports or coaxial interfaces. The expected simulated results of two manufactured prototypes operating at 19 GHz are compared with their experimental measurements. |
Carrasco, Eduardo; Barba, Mariano; Encinar, Jose A Reflectarray Element Based on Aperture-Coupled Patches With Slots and Lines of Variable Length Artículo de revista 55 , pp. 820–825, 2007, ISSN: 1558-2221. @article{Carrasco2007b, title = {Reflectarray Element Based on Aperture-Coupled Patches With Slots and Lines of Variable Length}, author = {Eduardo Carrasco and Mariano Barba and Jose A Encinar}, doi = {10.1109/TAP.2007.891863}, issn = {1558-2221}, year = {2007}, date = {2007-01-01}, volume = {55}, pages = {820--825}, publisher = {IEEE}, abstract = {A phase-shifter element for printed reflectarrays with more than 4 cycles of phase delay is presented in this work. The proposed reflectarray element allows very linear phase curves and is based on the combination of two previously studied and demonstrated concepts: variable length slots on a ground plane and patches coupled through a slot to variable length lines. In the former, the slots act as inductive loading on the patches depending on their length. With the second concept, the effect of nonconstant path delay is alleviated by the introduction of true-time delay (TTD) lines. The mixed effect allows a much larger range of phase delay to be reached and at the same time to improve the linearity of the phase delay behavior. Two ways of increasing the phase delay range are shown: the increase in length using U-shaped delay lines and the use of high permittivity substrates}, keywords = {}, pubstate = {published}, tppubtype = {article} } A phase-shifter element for printed reflectarrays with more than 4 cycles of phase delay is presented in this work. The proposed reflectarray element allows very linear phase curves and is based on the combination of two previously studied and demonstrated concepts: variable length slots on a ground plane and patches coupled through a slot to variable length lines. In the former, the slots act as inductive loading on the patches depending on their length. With the second concept, the effect of nonconstant path delay is alleviated by the introduction of true-time delay (TTD) lines. The mixed effect allows a much larger range of phase delay to be reached and at the same time to improve the linearity of the phase delay behavior. Two ways of increasing the phase delay range are shown: the increase in length using U-shaped delay lines and the use of high permittivity substrates |
Ruiz-Cruz, Jorge A; Zhang, Yunchi; Rebollar, Jesus M; Zaki, Kawthar A; Montejo-Garai, Jose R; Piloto, Andrew J TEM Mode-Matching analysis of multi-coupled strip-line filters Artículo en actas 2007 IEEE/MTT-S INTERNATIONAL MICROWAVE SYMPOSIUM DIGEST, VOLS 1-6, pp. 541-544, IEEE MTTS 2007, ISSN: 0149-645X, (IEEE/MTT-S International Microwave Symposium, Honolulu, HI, JUN 03-08, 2007). @inproceedings{RuizCruz2007a, title = {TEM Mode-Matching analysis of multi-coupled strip-line filters}, author = {Jorge A Ruiz-Cruz and Yunchi Zhang and Jesus M Rebollar and Kawthar A Zaki and Jose R Montejo-Garai and Andrew J Piloto}, doi = {10.1109/MWSYM.2007.380546}, issn = {0149-645X}, year = {2007}, date = {2007-01-01}, booktitle = {2007 IEEE/MTT-S INTERNATIONAL MICROWAVE SYMPOSIUM DIGEST, VOLS 1-6}, pages = {541-544}, organization = {IEEE MTTS}, series = {IEEE MTT-S International Microwave Symposium}, abstract = {The analysis of multi-coupled strip-line filters by the Mode-Matching method is studied for different input/output excitations. The aim is to compare the computational effort of two different options and to propose the most suitable formulation for the design of some! strip-line filters. It is shown that a suitable segmentation of the structure is essential for obtaining good numerical results. In fact, if the optimum segmentation is selected, a Mode-Matching analysis using only TEM modes can resemble the full-wave response, with shorter computation time. Hence, this approach can be very useful in design and different examples are shown to validate it, using other numerical methods and measurements of a ten order filter.}, note = {IEEE/MTT-S International Microwave Symposium, Honolulu, HI, JUN 03-08, 2007}, keywords = {}, pubstate = {published}, tppubtype = {inproceedings} } The analysis of multi-coupled strip-line filters by the Mode-Matching method is studied for different input/output excitations. The aim is to compare the computational effort of two different options and to propose the most suitable formulation for the design of some! strip-line filters. It is shown that a suitable segmentation of the structure is essential for obtaining good numerical results. In fact, if the optimum segmentation is selected, a Mode-Matching analysis using only TEM modes can resemble the full-wave response, with shorter computation time. Hence, this approach can be very useful in design and different examples are shown to validate it, using other numerical methods and measurements of a ten order filter. |
Ruiz-Cruz, Jorge A; Montejo-Garai, Jose R; Rebollar, Jesus M; Zaki, Kawthar A Waveguide filters with elliptical function response: Overview and results of different implementations Artículo de revista INTERNATIONAL JOURNAL OF RF AND MICROWAVE COMPUTER-AIDED ENGINEERING, 17 (1), pp. 63-69, 2007, ISSN: 1096-4290. @article{RuizCruz2007b, title = {Waveguide filters with elliptical function response: Overview and results of different implementations}, author = {Jorge A Ruiz-Cruz and Jose R Montejo-Garai and Jesus M Rebollar and Kawthar A Zaki}, doi = {10.1002/mmce.20198}, issn = {1096-4290}, year = {2007}, date = {2007-01-01}, journal = {INTERNATIONAL JOURNAL OF RF AND MICROWAVE COMPUTER-AIDED ENGINEERING}, volume = {17}, number = {1}, pages = {63-69}, abstract = {Some recent implementations of waveguide filters with elliptical response are presented in this paper. The goal is to describe the main aspects involved in the computer-aided design of elliptic waveguide filters, which are commonly used at microwave and millimeter-wave frequencies by their high selectivity, low insertion loss, and high power-handling capabilities. Three different examples based on crosscoupled cavities and the extracted-pole procedure are used to illustrate the main ideas, with their corresponding experimental results. A comparative table summarizes the main features of the presented filters. (C) 2006 Wiley Periodicals, Inc.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Some recent implementations of waveguide filters with elliptical response are presented in this paper. The goal is to describe the main aspects involved in the computer-aided design of elliptic waveguide filters, which are commonly used at microwave and millimeter-wave frequencies by their high selectivity, low insertion loss, and high power-handling capabilities. Three different examples based on crosscoupled cavities and the extracted-pole procedure are used to illustrate the main ideas, with their corresponding experimental results. A comparative table summarizes the main features of the presented filters. (C) 2006 Wiley Periodicals, Inc. |
2006 |
Barba, Mariano; Page, J E; Encinar, Jose A; Montejo-Garai, Jose R A switchable multiple beam antenna for GSM-UMTS base stations in planar technology Artículo de revista IEEE TRANSACTIONS ON ANTENNAS AND PROPAGATION, 54 (11, 1), pp. 3087-3094, 2006, ISSN: 0018-926X. @article{Barba2006, title = {A switchable multiple beam antenna for GSM-UMTS base stations in planar technology}, author = {Mariano Barba and J E Page and Jose A Encinar and Jose R Montejo-Garai}, doi = {10.1109/TAP.2006.883991}, issn = {0018-926X}, year = {2006}, date = {2006-11-01}, journal = {IEEE TRANSACTIONS ON ANTENNAS AND PROPAGATION}, volume = {54}, number = {11, 1}, pages = {3087-3094}, abstract = {A broadband antenna for GSM1800-UMTS base stations with multiple switchable beams in azimuth is presented in this paper. The multiple beams are obtained by means of a broadband Butler matrix. The radiating element is broadband and consists of two stacked patches. The elevation pattern is shaped with null filling and upper lobe reduction that has been achieved by means of a broadband corporate feed network implemented in microstrip technology. Photographs and measurements of the manufactured prototypes are presented confirming that the design of all of the elements is correct.}, keywords = {}, pubstate = {published}, tppubtype = {article} } A broadband antenna for GSM1800-UMTS base stations with multiple switchable beams in azimuth is presented in this paper. The multiple beams are obtained by means of a broadband Butler matrix. The radiating element is broadband and consists of two stacked patches. The elevation pattern is shaped with null filling and upper lobe reduction that has been achieved by means of a broadband corporate feed network implemented in microstrip technology. Photographs and measurements of the manufactured prototypes are presented confirming that the design of all of the elements is correct. |
Datashvili, Leri Sh.; Baier, Horst; Encinar, Jose A; Legay, Herve Mechanical investigation of a multi-layer reflectarray for Ku-band space antennas Artículo de revista AEROSPACE SCIENCE AND TECHNOLOGY, 10 (7), pp. 618-627, 2006, ISSN: 1270-9638. @article{Datashvili2006, title = {Mechanical investigation of a multi-layer reflectarray for Ku-band space antennas}, author = {Leri Sh. Datashvili and Horst Baier and Jose A Encinar and Herve Legay}, doi = {10.1016/j.ast.2006.06.007}, issn = {1270-9638}, year = {2006}, date = {2006-10-01}, journal = {AEROSPACE SCIENCE AND TECHNOLOGY}, volume = {10}, number = {7}, pages = {618-627}, abstract = {A multi layer sandwich panel of printed reflectarray (RA) is a complex composition of many different materials enabling a required performance with exceptional properties. The major properties of a multilayer RA include the following: the use of array layers of reflective patches forming the flat structure gives the possibility to focus the electromagnetic waves; the use of more than one reflecting layer is widening the RF bandwidth; the possibility of having two different polarisations and two different contours of the beams. To achieve the mentioned properties, analytical and experimental investigations have been carried out. A sandwich panel for a three-layer printed reflectarray for dual polarisation with a different coverage in each polarisation has been designed, manufactured and tested. The measured radiation patterns of the RA show that gain requirements are fulfilled in a 10% bandwidth. Thickness and flatness accuracy requirements are also fulfilled. Low dissipative electric losses (0.35 dB) have been achieved, as a result of an appropriate mechanical design and selection of low-loss materials for the RA panel. (c) 2006 Elsevier Masson SAS. All rights reserved.}, keywords = {}, pubstate = {published}, tppubtype = {article} } A multi layer sandwich panel of printed reflectarray (RA) is a complex composition of many different materials enabling a required performance with exceptional properties. The major properties of a multilayer RA include the following: the use of array layers of reflective patches forming the flat structure gives the possibility to focus the electromagnetic waves; the use of more than one reflecting layer is widening the RF bandwidth; the possibility of having two different polarisations and two different contours of the beams. To achieve the mentioned properties, analytical and experimental investigations have been carried out. A sandwich panel for a three-layer printed reflectarray for dual polarisation with a different coverage in each polarisation has been designed, manufactured and tested. The measured radiation patterns of the RA show that gain requirements are fulfilled in a 10% bandwidth. Thickness and flatness accuracy requirements are also fulfilled. Low dissipative electric losses (0.35 dB) have been achieved, as a result of an appropriate mechanical design and selection of low-loss materials for the RA panel. (c) 2006 Elsevier Masson SAS. All rights reserved. |
Encinar, Jose A; Datashvili, Leri Sh.; Zornoza, JA; Arrebola, Manuel; Sierra-Castaner, Manuel; Besada-Sanmartin, Jose Luis; Baier, Horst; Legay, Herve Dual-polarization dual-coverage reflectarray for space applications Artículo de revista IEEE TRANSACTIONS ON ANTENNAS AND PROPAGATION, 54 (10), pp. 2827-2837, 2006, ISSN: 0018-926X. @article{Encinar2006, title = {Dual-polarization dual-coverage reflectarray for space applications}, author = {Jose A Encinar and Leri Sh. Datashvili and JA Zornoza and Manuel Arrebola and Manuel Sierra-Castaner and Jose Luis Besada-Sanmartin and Horst Baier and Herve Legay}, doi = {10.1109/TAP.2006.882172}, issn = {0018-926X}, year = {2006}, date = {2006-10-01}, journal = {IEEE TRANSACTIONS ON ANTENNAS AND PROPAGATION}, volume = {54}, number = {10}, pages = {2827-2837}, abstract = {A breadboard of a three-layer printed reflectarray for dual polarization with a different coverage in each polarization has been designed, manufactured, and tested. The reflectarray consists of three layers of rectangular patch arrays separated by a honeycomb and backed by a ground plane. The beam shaping for each polarization is achieved by adjusting the phase of the reflection coefficient at each reflective element independently for each linear polarization. The phase shift for each polarization is controlled by varying either the x or y patch dimensions. The dimensions of the rectangular patches are optimized to achieve the required phase shift for each beam at central and extreme frequencies in the working band. The reflectarray has been designed to produce a contoured beam for a European coverage in H-polarization in a 10% bandwidth, and a pencil beam to illuminate the East Coast in North America in V-polarization. The measured radiation patterns show that gain requirements are practically fulfilled in a 10% bandwidth for both coverages, and the electrical performances of the breadboard are close to those of a classical dual gridded reflector.}, keywords = {}, pubstate = {published}, tppubtype = {article} } A breadboard of a three-layer printed reflectarray for dual polarization with a different coverage in each polarization has been designed, manufactured, and tested. The reflectarray consists of three layers of rectangular patch arrays separated by a honeycomb and backed by a ground plane. The beam shaping for each polarization is achieved by adjusting the phase of the reflection coefficient at each reflective element independently for each linear polarization. The phase shift for each polarization is controlled by varying either the x or y patch dimensions. The dimensions of the rectangular patches are optimized to achieve the required phase shift for each beam at central and extreme frequencies in the working band. The reflectarray has been designed to produce a contoured beam for a European coverage in H-polarization in a 10% bandwidth, and a pencil beam to illuminate the East Coast in North America in V-polarization. The measured radiation patterns show that gain requirements are practically fulfilled in a 10% bandwidth for both coverages, and the electrical performances of the breadboard are close to those of a classical dual gridded reflector. |
Esteban, J; Page, J E; Martín-Guerrero, T M; Camacho-Peñalosa, C Using a Thin-strips Periodic Structure to Obtain a Left-handed Equivalent Transmission Line for the Evanescent TM Mode Artículo de revista IJMOT, International Journal of Microwave and Optical Technology, 1 (2), pp. 464-469, 2006. @article{Esteban2006, title = {Using a Thin-strips Periodic Structure to Obtain a Left-handed Equivalent Transmission Line for the Evanescent TM Mode}, author = {J Esteban and J E Page and T M Martín-Guerrero and C Camacho-Peñalosa}, url = {http://www.ijmot.com/VOL1NO11.ASPX}, year = {2006}, date = {2006-08-01}, journal = {IJMOT, International Journal of Microwave and Optical Technology}, volume = {1}, number = {2}, pages = {464-469}, abstract = {The equivalences between evanescent TM modes and negative permeability media and between periodic thin-wires structures and electric plasmas have been exploited, in order to design a periodic square waveguide that supports a backward-wave TM mode, whose equivalent transmission line can be considered as a Left-Handed Transmission Line (LHTL). Realizable waveguide fillings are proposed, and some theoretical and experimental results are presented. How to extract the macroscopic parameters of the implemented artificial dielectric plasmas is also shown.}, keywords = {}, pubstate = {published}, tppubtype = {article} } The equivalences between evanescent TM modes and negative permeability media and between periodic thin-wires structures and electric plasmas have been exploited, in order to design a periodic square waveguide that supports a backward-wave TM mode, whose equivalent transmission line can be considered as a Left-Handed Transmission Line (LHTL). Realizable waveguide fillings are proposed, and some theoretical and experimental results are presented. How to extract the macroscopic parameters of the implemented artificial dielectric plasmas is also shown. |
2008 |
Analysis of Slotted Antennas on Metamaterial Waveguides Artículo en actas Proceedings of the VI Iberian Meeting on Computational Electromagnetics (EIEC), Chiclana de la Frontera, Cádiz (Spain), 2008. |
Time Domain Dosimetry in Layered Media Artículo en actas 38th European Microwave Conference (EuMC), pp. 79 -82, Amsterdam (Denmark), 2008. |
Demonstration of a Shaped Beam Reflectarray Using Aperture-Coupled Delay Lines for LMDS Central Station Antenna Artículo de revista IEEE TRANSACTIONS ON ANTENNAS AND PROPAGATION, 56 (10), pp. 3103-3111, 2008, ISSN: 0018-926X. |
Design and Measurement of Reconfigurable Millimeter Wave Reflectarray Cells with Nematic Liquid Crystal Artículo de revista IEEE TRANSACTIONS ON ANTENNAS AND PROPAGATION, 56 (10), pp. 3112-3117, 2008, ISSN: 0018-926X. |
Frequency Scanning Capabilities of a Long Slot in a Metamaterial-Based Waveguide Artículo en actas Proceedings of the 2nd International Congress on Advanced Electromagnetic Materials in Microwaves and Optics (METAMATERIALS), pp. 696-698, Pamplona (Spain), 2008, (ISBN 978-84-9769-229-8). |
Modelling the Coupling Between Microstrip Ring-resonators and Transmission Lines by a Microwave Circuit-Based Approach Artículo en actas Proceedings of the 2nd International Congress on Advanced Electromagnetic Materials in Microwaves and Optics (METAMATERIALS), pp. 641-643, Pamplona (Spain), 2008, (ISBN 978-84-9769-229-8). |
Finite element analysis of periodic structures without constrained meshes Artículo de revista IEEE TRANSACTIONS ON ANTENNAS AND PROPAGATION, 56 (9), pp. 3020-3028, 2008, ISSN: 0018-926X. |
Cad of stacked patch antennas through multipurpose admittance matrices from FEM and neural networks Artículo de revista MICROWAVE AND OPTICAL TECHNOLOGY LETTERS, 50 (9), pp. 2411-2416, 2008, ISSN: 0895-2477. |
Frequency notched UWB planar monopole antenna optimization using a finite element method-based approach Artículo de revista IEEE TRANSACTIONS ON ANTENNAS AND PROPAGATION, 56 (9), pp. 2884-2893, 2008, ISSN: 0018-926X. |
Bandwidth improvement in large reflectarrays by using true-time delay Artículo de revista IEEE TRANSACTIONS ON ANTENNAS AND PROPAGATION, 56 (8, 2), pp. 2496-2503, 2008, ISSN: 0018-926X. |
Time Domain Dosimetry in Planar Layered Media Artículo en actas European Electromagnetics (EUROEM), Lausanne (Switzerland), 2008. |
Full-wave modeling and optimization of Boifot junction ortho-mode transducers Artículo de revista INTERNATIONAL JOURNAL OF RF AND MICROWAVE COMPUTER-AIDED ENGINEERING, 18 (4), pp. 303-313, 2008, ISSN: 1096-4290. |
Multifed printed reflectarray with three simultaneous shaped beams for LMDS central station antenna Artículo de revista IEEE TRANSACTIONS ON ANTENNAS AND PROPAGATION, 56 (6), pp. 1518-1527, 2008, ISSN: 0018-926X. |
Optimized profile planar UWB monopole antenna for optimal adaptation Artículo en actas 2008 IEEE ANTENNAS AND PROPAGATION SOCIETY INTERNATIONAL SYMPOSIUM, VOLS 1-9, pp. 823-826, IEEE 2008, ISSN: 1522-3965, (IEEE Antennas-and-Propagation-Society International Symposium, San Diego, CA, JUL 05-11, 2008). |
Optimization of Frequency Notched UWB Monopole Antennas by means of Genetic Algorithms with Multipurpose Admitance Matrix Analysis Approach Artículo en actas San Diego, USA, 2008. |
Study of Axisymmetric dielectric resonators in MIC Environments based on Finite Elements Artículo en actas San Diego, USA, 2008. |
Optimized Profile Monopole Antennas through Finite Elements for UWB Applications Artículo en actas Bonn, Germany. Conferencia Invitada, 2008. |
Optimized profile dielectric coating in UWB monopole antenna for radiation pattern gain stability and optimal adaptation Artículo en actas Noordwijk. Holland, 2008. |
Reflectarray Antennas Capítulo de libro REFLECTARRAY ANTENNAS, pp. 1-216, 2008, ISBN: 978-0-470-17877-5. |
Introduction to Reflectarray Antenna Capítulo de libro REFLECTARRAY ANTENNAS, pp. 1-7, 2008, ISBN: 978-0-470-17877-5. |
Development History Capítulo de libro REFLECTARRAY ANTENNAS, pp. 9-26, 2008, ISBN: 978-0-470-17877-5; 978-0-470-08491-5. |
Antenna Analysis Techniques Capítulo de libro REFLECTARRAY ANTENNAS, pp. 27-78, 2008, ISBN: 978-0-470-17877-5; 978-0-470-08491-5. |
Practical Design Approach Capítulo de libro REFLECTARRAY ANTENNAS, pp. 79-92, 2008, ISBN: 978-0-470-17877-5. |
Broadband Techniques Capítulo de libro REFLECTARRAY ANTENNAS, pp. 93-118, 2008, ISBN: 978-0-470-17877-5. |
Dual-Band Reflectarray Capítulo de libro REFLECTARRAY ANTENNAS, pp. 119-135, 2008, ISBN: 978-0-470-17877-5. |
Recent and Future Applications Capítulo de libro REFLECTARRAY ANTENNAS, pp. 137-205, 2008, ISBN: 978-0-470-17877-5; 978-0-470-08491-5. |
Longitudinal Dual-Mode Filters in Rectangular Waveguide Artículo en actas 2008 IEEE MTT-S INTERNATIONAL MICROWAVE SYMPOSIUM DIGEST, VOLS 1-4, pp. 631-634, IEEE 2008, ISSN: 0149-645X, (2008 IEEE MTT-S International Microwave Symposium Digest, Atlanta, GA, JUN 15-20, 2008). |
COMPACT FULL KU-BAND TRIPLEXER WITH IMPROVED E-PLANE POWER DIVIDER Artículo de revista PROGRESS IN ELECTROMAGNETICS RESEARCH-PIER, 86 , pp. 39-51, 2008. |
2007 |
On the Equivalent Circuits of Microstripline and Slotline Pendry-like Resonators Coupled to Microstrip Lines Artículo en actas Proceedings of the 11th International Symposium on Microwave and Optical Technology (ISMOT), pp. 155-158, Villa Mondragone, Monte Porzio Catone (Italy), 2007, (ISBN 978-88-548-1476-9). |
Reflectarray Antennas Libro John Wiley & Sons, 2007, ISBN: 047008491X. |
Exact Analysis of the Wire-Bonded Multiconductor Transmission Line Artículo de revista IEEE Transactions on Microwave Theory and Techniques, 55 (8), pp. 1585-1592, 2007, ISSN: 0018-9480. |
Liquid-crystal-based reflectarray antenna with electronically switchable monopulse patterns Artículo de revista ELECTRONICS LETTERS, 43 (14), pp. 744-745, 2007, ISSN: 0013-5194. |
Ultrawideband optimized profile monopole antenna by means of simulated annealing algorithm and the finite element method Artículo de revista IEEE TRANSACTIONS ON ANTENNAS AND PROPAGATION, 55 (6, 2), pp. 1826-1832, 2007, ISSN: 0018-926X. |
On the two dimension applications of high-order vector finite elements to the study of electromagnetic resonance Artículo de revista IET MICROWAVES ANTENNAS & PROPAGATION, 1 (2), pp. 306-313, 2007, ISSN: 1751-8725. |
Reflectarray element based on aperture-coupled patches with slots and lines of variable length Artículo de revista IEEE TRANSACTIONS ON ANTENNAS AND PROPAGATION, 55 (3, 2), pp. 820-825, 2007, ISSN: 0018-926X. |
Analysis of cylindrical and spherical dielectric resonators in cavities by means of finite elements Artículo en actas {Bonefacic, D} (Ed.): ICECOM 2007: 19TH INTERNATIONAL CONFERENCE ON APPLIED ELECTROMAGNETICS AND COMMUNICATIONS, CONFERENCE PROCEEDINGS, pp. 279-282, 2007, ISBN: 978-953-6037-50-6, (19th International Conference on Applied Electromagnetics and Communications, Dubrovnik, CROATIA, SEP 24-26, 2007). |
Optimization of the Profile of a Planar Ultra Wide Band Monopole Antenna in Order to Minimize Return Losses Artículo en actas pp. 1–5, IET, Edinburgh, 2007, ISSN: 0537-9989. |
Hybrid Vector-Scalar Finite Elements for Curved-Triangle Meshes Applied to the Study of Electromagnetic Resonances Artículo en actas pp. 1–4, IET, Edinburgh, 2007, ISSN: 0537-9989. |
Reduction of cross-polarization in contoured beam reflectarrays using a three-layer configuration Artículo en actas 2007 IEEE ANTENNAS AND PROPAGATION SOCIETY INTERNATIONAL SYMPOSIUM, VOLS 1-12, pp. 4833-4836, IEEE; Antennas & Propagat Soc 2007, ISSN: 1522-3965, (IEEE Antennas-and-Propagation-Society International Symposium, Honolulu, HI, JUN 09-15, 2007). |
Printed Reflectarray Antennas Capítulo de libro {Waterhouse, R} (Ed.): PRINTED ANTENNAS FOR WIRELESS COMMUNICATIONS, pp. 299-330, 2007, ISBN: 978-0-470-51224-1. |
A Parabolic Reflectarray for a Bandwidth Improved Contoured Beam Coverage Artículo en actas pp. 1–5, IET, Edinburgh, 2007, ISSN: 0537-9989. |
Design of a Tx/Rx Reflectarray Antenna for Space Applications Artículo en actas pp. 1–5, IET, Edinburgh, 2007, ISSN: 0537-9989. |
Design of Riblet-type couplers for Ka band applications Artículo en actas 2007 IEEE ANTENNAS AND PROPAGATION SOCIETY INTERNATIONAL SYMPOSIUM, VOLS 1-12, pp. 4276-4279, IEEE; Antennas & Propagat Soc 2007, ISSN: 1522-3965, (IEEE Antennas-and-Propagation-Society International Symposium, Honolulu, HI, JUN 09-15, 2007). |
Reflectarray Element Based on Aperture-Coupled Patches With Slots and Lines of Variable Length Artículo de revista 55 , pp. 820–825, 2007, ISSN: 1558-2221. |
TEM Mode-Matching analysis of multi-coupled strip-line filters Artículo en actas 2007 IEEE/MTT-S INTERNATIONAL MICROWAVE SYMPOSIUM DIGEST, VOLS 1-6, pp. 541-544, IEEE MTTS 2007, ISSN: 0149-645X, (IEEE/MTT-S International Microwave Symposium, Honolulu, HI, JUN 03-08, 2007). |
Waveguide filters with elliptical function response: Overview and results of different implementations Artículo de revista INTERNATIONAL JOURNAL OF RF AND MICROWAVE COMPUTER-AIDED ENGINEERING, 17 (1), pp. 63-69, 2007, ISSN: 1096-4290. |
2006 |
A switchable multiple beam antenna for GSM-UMTS base stations in planar technology Artículo de revista IEEE TRANSACTIONS ON ANTENNAS AND PROPAGATION, 54 (11, 1), pp. 3087-3094, 2006, ISSN: 0018-926X. |
Mechanical investigation of a multi-layer reflectarray for Ku-band space antennas Artículo de revista AEROSPACE SCIENCE AND TECHNOLOGY, 10 (7), pp. 618-627, 2006, ISSN: 1270-9638. |
Dual-polarization dual-coverage reflectarray for space applications Artículo de revista IEEE TRANSACTIONS ON ANTENNAS AND PROPAGATION, 54 (10), pp. 2827-2837, 2006, ISSN: 0018-926X. |
Using a Thin-strips Periodic Structure to Obtain a Left-handed Equivalent Transmission Line for the Evanescent TM Mode Artículo de revista IJMOT, International Journal of Microwave and Optical Technology, 1 (2), pp. 464-469, 2006. |
