2016 |
Douglas, M G; Portelli, L; Carrasco, Eduardo; Christ, A; Jain, N; Kuster, N Comprehensive Validation and Uncertainty Evaluation of New SAR Measurement Technologies Artículo en actas 2016 10TH EUROPEAN CONFERENCE ON ANTENNAS AND PROPAGATION (EUCAP), 2016, ISSN: 2164-3342, (10th European Conference on Antennas and Propagation (EuCAP), Davos, SWITZERLAND, APR 10-15, 2016). @inproceedings{ISI:000400784900146, title = {Comprehensive Validation and Uncertainty Evaluation of New SAR Measurement Technologies}, author = {M G Douglas and L Portelli and Eduardo Carrasco and A Christ and N Jain and N Kuster}, doi = {10.1109/eucap.2016.7481243}, issn = {2164-3342}, year = {2016}, date = {2016-01-01}, booktitle = {2016 10TH EUROPEAN CONFERENCE ON ANTENNAS AND PROPAGATION (EUCAP)}, series = {Proceedings of the European Conference on Antennas and Propagation}, abstract = {Novel measurement technologies for specific absorption rate (SAR) assessment of wireless devices have been developed using sensor arrays to dramatically reduce the measurement time compared to single-probe scanning systems. While single-probe scanning systems are optimized for low measurement uncertainty and source-independent accuracy, array systems are in widespread use for design testing and have made significant advances in accuracy. This has encouraged regulatory agencies and standards organization to develop procedures for their use in compliance testing of wireless devices. Central to the acceptance of array systems are comprehensive procedures for the validation of the measurement accuracy and determination of the measurement uncertainty. In this paper, a validation protocol is proposed. The protocol is applied using a popular sensor array system. The results are used to demonstrate the conservativeness of the uncertainty budget.}, note = {10th European Conference on Antennas and Propagation (EuCAP), Davos, SWITZERLAND, APR 10-15, 2016}, keywords = {}, pubstate = {published}, tppubtype = {inproceedings} } Novel measurement technologies for specific absorption rate (SAR) assessment of wireless devices have been developed using sensor arrays to dramatically reduce the measurement time compared to single-probe scanning systems. While single-probe scanning systems are optimized for low measurement uncertainty and source-independent accuracy, array systems are in widespread use for design testing and have made significant advances in accuracy. This has encouraged regulatory agencies and standards organization to develop procedures for their use in compliance testing of wireless devices. Central to the acceptance of array systems are comprehensive procedures for the validation of the measurement accuracy and determination of the measurement uncertainty. In this paper, a validation protocol is proposed. The protocol is applied using a popular sensor array system. The results are used to demonstrate the conservativeness of the uncertainty budget. |
Carrasco, Eduardo; Tamagnone, M; Low, T; Capstick, M H; Mosig, J R Mid-Infrared Reflectarrays Based on an Aperiodic Graphene Nanostrips Array Artículo en actas 10th European Conference on Antennas and Propagation (EuCAP 2016), 2016. @inproceedings{, title = {Mid-Infrared Reflectarrays Based on an Aperiodic Graphene Nanostrips Array}, author = {Eduardo Carrasco and M Tamagnone and T Low and M H Capstick and J R Mosig}, year = {2016}, date = {2016-01-01}, booktitle = {10th European Conference on Antennas and Propagation (EuCAP 2016)}, keywords = {}, pubstate = {published}, tppubtype = {inproceedings} } |
Abdollahvand, M; Encinar, Jose A; Forooraghi, K; Atlasbaf, Z; Barba, Mariano Single-Layer Dual-Frequency Reflectarray for Ka-Band Antennas Artículo en actas 2016 10TH EUROPEAN CONFERENCE ON ANTENNAS AND PROPAGATION (EUCAP), 2016, ISSN: 2164-3342, (10th European Conference on Antennas and Propagation (EuCAP), Davos, SWITZERLAND, APR 10-15, 2016). @inproceedings{Abdollahvand2016, title = {Single-Layer Dual-Frequency Reflectarray for Ka-Band Antennas}, author = {M Abdollahvand and Jose A Encinar and K Forooraghi and Z Atlasbaf and Mariano Barba}, issn = {2164-3342}, year = {2016}, date = {2016-01-01}, booktitle = {2016 10TH EUROPEAN CONFERENCE ON ANTENNAS AND PROPAGATION (EUCAP)}, series = {Proceedings of the European Conference on Antennas and Propagation}, abstract = {A novel single layer, dual-polarization reflectarray is proposed to operate at transmit (30 GHz) and receive (20 GHz) frequencies for Ka-band terminal antennas. The proposed reflectarray antenna is based on a unit cell with several resonant elements of adjustable length printed on the same side of a conductor backed substrate. Crossed dipoles and truncated rectangular rings are used to adjust the phase at 30 GHz, while cross-shaped loops are used for the phasing at 20 GHz. The adjustment of phase in each element is made by varying the resonant length of the printed elements. An 18-cm reflectarray antenna with separate feeds for 20 GHz and 30 GHz has been designed and analyzed. The simulated results show satisfactory focused beams with a gain of 30.6 dBi at 20 GHz and 33.7 dBi at 30 GHz.}, note = {10th European Conference on Antennas and Propagation (EuCAP), Davos, SWITZERLAND, APR 10-15, 2016}, keywords = {}, pubstate = {published}, tppubtype = {inproceedings} } A novel single layer, dual-polarization reflectarray is proposed to operate at transmit (30 GHz) and receive (20 GHz) frequencies for Ka-band terminal antennas. The proposed reflectarray antenna is based on a unit cell with several resonant elements of adjustable length printed on the same side of a conductor backed substrate. Crossed dipoles and truncated rectangular rings are used to adjust the phase at 30 GHz, while cross-shaped loops are used for the phasing at 20 GHz. The adjustment of phase in each element is made by varying the resonant length of the printed elements. An 18-cm reflectarray antenna with separate feeds for 20 GHz and 30 GHz has been designed and analyzed. The simulated results show satisfactory focused beams with a gain of 30.6 dBi at 20 GHz and 33.7 dBi at 30 GHz. |
Abdollahvand, M; Encinar, Jose A; Forooraghi, K; Atlasbaf, Z; Page, J E Tri-Band FSS for Ku/Ka Bands Reflector Antennas Artículo en actas 2016 10TH EUROPEAN CONFERENCE ON ANTENNAS AND PROPAGATION (EUCAP), 2016, ISSN: 2164-3342, (10th European Conference on Antennas and Propagation (EuCAP), Davos, SWITZERLAND, APR 10-15, 2016). @inproceedings{Abdollahvand2016a, title = {Tri-Band FSS for Ku/Ka Bands Reflector Antennas}, author = {M Abdollahvand and Jose A Encinar and K Forooraghi and Z Atlasbaf and J E Page}, issn = {2164-3342}, year = {2016}, date = {2016-01-01}, booktitle = {2016 10TH EUROPEAN CONFERENCE ON ANTENNAS AND PROPAGATION (EUCAP)}, series = {Proceedings of the European Conference on Antennas and Propagation}, abstract = {A tri-band frequency selective surface (FSS) is presented for Ku and Ka bands for space communications. The FSS is designed to be transparent in the frequency range 10.7 GHz-12.05 GHz and to provide total reflection at 20 GHz and 30 GHz, Ku-and Ka-band in satellite communications, respectively. A single square ring with two pairs of dipoles are used in each FSS unit cell to obtain this performance. The simulation of the transmission and reflection coefficients for the proposed FSS, under normal and oblique TE and TM incidences, show satisfactory results for the reflection and transmission bands with a stable frequency response at oblique incidence angles.}, note = {10th European Conference on Antennas and Propagation (EuCAP), Davos, SWITZERLAND, APR 10-15, 2016}, keywords = {}, pubstate = {published}, tppubtype = {inproceedings} } A tri-band frequency selective surface (FSS) is presented for Ku and Ka bands for space communications. The FSS is designed to be transparent in the frequency range 10.7 GHz-12.05 GHz and to provide total reflection at 20 GHz and 30 GHz, Ku-and Ka-band in satellite communications, respectively. A single square ring with two pairs of dipoles are used in each FSS unit cell to obtain this performance. The simulation of the transmission and reflection coefficients for the proposed FSS, under normal and oblique TE and TM incidences, show satisfactory results for the reflection and transmission bands with a stable frequency response at oblique incidence angles. |
Florencio, Rafael; Encinar, Jose A; Boix, Rafael R; Perez-Palomino, Gerardo; Toso, Giovanni Cross-polar Reduction in Reflectarray Antennas by means of Element Rotation Artículo en actas 2016 10TH EUROPEAN CONFERENCE ON ANTENNAS AND PROPAGATION (EUCAP), 2016, ISSN: 2164-3342, (10th European Conference on Antennas and Propagation (EuCAP), Davos, SWITZERLAND, APR 10-15, 2016). @inproceedings{Florencio2016, title = {Cross-polar Reduction in Reflectarray Antennas by means of Element Rotation}, author = {Rafael Florencio and Jose A Encinar and Rafael R Boix and Gerardo Perez-Palomino and Giovanni Toso}, issn = {2164-3342}, year = {2016}, date = {2016-01-01}, booktitle = {2016 10TH EUROPEAN CONFERENCE ON ANTENNAS AND PROPAGATION (EUCAP)}, series = {Proceedings of the European Conference on Antennas and Propagation}, abstract = {A cross-polar reduction technique for dual-polarization reflectarray antennas is proposed. This technique is based on the determination of the rotation angle of each reflectarray element that minimizes the cross-polar components of the electric and magnetic fields reflected by that particular element in each polarization under local periodicity assumption. The results obtained with the cross-polar reduction technique have been validated by comparison with results provided by the commercial software CST (R). The technique has been applied to the reduction of the cross-polarization radiated by a dual-polarization transmit-receive reflectarray antenna. The results obtained after cross-polar reduction show minimum values of cross-polar discrimination of 35 dB for one polarization and 40 dB for the orthogonal polarization, both in the Tx and Rx-bands.}, note = {10th European Conference on Antennas and Propagation (EuCAP), Davos, SWITZERLAND, APR 10-15, 2016}, keywords = {}, pubstate = {published}, tppubtype = {inproceedings} } A cross-polar reduction technique for dual-polarization reflectarray antennas is proposed. This technique is based on the determination of the rotation angle of each reflectarray element that minimizes the cross-polar components of the electric and magnetic fields reflected by that particular element in each polarization under local periodicity assumption. The results obtained with the cross-polar reduction technique have been validated by comparison with results provided by the commercial software CST (R). The technique has been applied to the reduction of the cross-polarization radiated by a dual-polarization transmit-receive reflectarray antenna. The results obtained after cross-polar reduction show minimum values of cross-polar discrimination of 35 dB for one polarization and 40 dB for the orthogonal polarization, both in the Tx and Rx-bands. |
Pino, Antonio Garcia; Gonzalez-Valdes, Borja; Rubinos, Oscar; Encinar, Jose A A Confocal Reflector for a Reflectarray-based Scanning System Artículo en actas 2016 10TH EUROPEAN CONFERENCE ON ANTENNAS AND PROPAGATION (EUCAP), 2016, ISSN: 2164-3342, (10th European Conference on Antennas and Propagation (EuCAP), Davos, SWITZERLAND, APR 10-15, 2016). @inproceedings{GarciaPino2016, title = {A Confocal Reflector for a Reflectarray-based Scanning System}, author = {Antonio Garcia Pino and Borja Gonzalez-Valdes and Oscar Rubinos and Jose A Encinar}, issn = {2164-3342}, year = {2016}, date = {2016-01-01}, booktitle = {2016 10TH EUROPEAN CONFERENCE ON ANTENNAS AND PROPAGATION (EUCAP)}, series = {Proceedings of the European Conference on Antennas and Propagation}, abstract = {In this work, an electronically scanned reflectarray is combined with a reflector system based on a Confocal configuration in order to obtain a pencil beam steering. A ray tracing technique is used to specify the reflectarray optimal position and size. The main novelty of this research is that the phase shift in the reflectarray elements is calculated in such a way that allows for both beam steering and compensation of the residual phase aberration at the same time. The antenna behavior is evaluated using ray tracing to analyze the phase aberrations in the system and Physical Optics to predict the antenna pattern. A set of representative simulation results showing the good scanning performance of the proposed system are presented.}, note = {10th European Conference on Antennas and Propagation (EuCAP), Davos, SWITZERLAND, APR 10-15, 2016}, keywords = {}, pubstate = {published}, tppubtype = {inproceedings} } In this work, an electronically scanned reflectarray is combined with a reflector system based on a Confocal configuration in order to obtain a pencil beam steering. A ray tracing technique is used to specify the reflectarray optimal position and size. The main novelty of this research is that the phase shift in the reflectarray elements is calculated in such a way that allows for both beam steering and compensation of the residual phase aberration at the same time. The antenna behavior is evaluated using ray tracing to analyze the phase aberrations in the system and Physical Optics to predict the antenna pattern. A set of representative simulation results showing the good scanning performance of the proposed system are presented. |
Martinez-de-Rioja, Eduardo; Encinar, Jose A; Florencio, Rafael; Boix, Rafael R Dual Polarized Reflectarray Antenna to Generate Independent Beams in Ku and Ka Bands Artículo en actas 2016 10TH EUROPEAN CONFERENCE ON ANTENNAS AND PROPAGATION (EUCAP), 2016, ISSN: 2164-3342, (10th European Conference on Antennas and Propagation (EuCAP), Davos, SWITZERLAND, APR 10-15, 2016). @inproceedings{MartinezdeRioja2016, title = {Dual Polarized Reflectarray Antenna to Generate Independent Beams in Ku and Ka Bands}, author = {Eduardo Martinez-de-Rioja and Jose A Encinar and Rafael Florencio and Rafael R Boix}, issn = {2164-3342}, year = {2016}, date = {2016-01-01}, booktitle = {2016 10TH EUROPEAN CONFERENCE ON ANTENNAS AND PROPAGATION (EUCAP)}, series = {Proceedings of the European Conference on Antennas and Propagation}, abstract = {This contribution describes the design of a printed reflectarray antenna for operating at Ku and Ka frequency bands. The reflectarray has been designed to produce a focused beam at 11.95 and 20 GHz for both Horizontal and Vertical polarizations. The antenna is illuminated by a corrugated horn, modelled as a cos-q function with different q-factor values at 11.95 and 20 GHz. The periodic element is made of two stacked sets of dipoles, each of one comprising two orthogonal subsets of coplanar parallel dipoles, whose lengths are adjusted to focus the beam at each polarization and frequency band. The dimensions of all dipoles are calculated for a circular reflectarray of 33x33 elements (33-cm sided), using a MoM-SD based analysis routine and local periodicity approach. The simulated radiation patterns of the antenna show a gain of 30.7 dBi at 11.95 GHz and 34.2 dBi at 20 GHz, with side-lobe levels close to -21 dB.}, note = {10th European Conference on Antennas and Propagation (EuCAP), Davos, SWITZERLAND, APR 10-15, 2016}, keywords = {}, pubstate = {published}, tppubtype = {inproceedings} } This contribution describes the design of a printed reflectarray antenna for operating at Ku and Ka frequency bands. The reflectarray has been designed to produce a focused beam at 11.95 and 20 GHz for both Horizontal and Vertical polarizations. The antenna is illuminated by a corrugated horn, modelled as a cos-q function with different q-factor values at 11.95 and 20 GHz. The periodic element is made of two stacked sets of dipoles, each of one comprising two orthogonal subsets of coplanar parallel dipoles, whose lengths are adjusted to focus the beam at each polarization and frequency band. The dimensions of all dipoles are calculated for a circular reflectarray of 33x33 elements (33-cm sided), using a MoM-SD based analysis routine and local periodicity approach. The simulated radiation patterns of the antenna show a gain of 30.7 dBi at 11.95 GHz and 34.2 dBi at 20 GHz, with side-lobe levels close to -21 dB. |
Prado, Daniel Rodriguez; Arrebola, Manuel; Pino, Marcos R; Las-Heras, Fernando; Florencio, Rafael; Boix, Rafael R; Encinar, Jose A Reflectarray Antenna with Reduced Crosspolar Radiation Pattern Artículo en actas 2016 10TH EUROPEAN CONFERENCE ON ANTENNAS AND PROPAGATION (EUCAP), 2016, ISSN: 2164-3342, (10th European Conference on Antennas and Propagation (EuCAP), Davos, SWITZERLAND, APR 10-15, 2016). @inproceedings{Prado2016a, title = {Reflectarray Antenna with Reduced Crosspolar Radiation Pattern}, author = {Daniel Rodriguez Prado and Manuel Arrebola and Marcos R Pino and Fernando Las-Heras and Rafael Florencio and Rafael R Boix and Jose A Encinar}, issn = {2164-3342}, year = {2016}, date = {2016-01-01}, booktitle = {2016 10TH EUROPEAN CONFERENCE ON ANTENNAS AND PROPAGATION (EUCAP)}, series = {Proceedings of the European Conference on Antennas and Propagation}, abstract = {A method for the optimization of the crosspolar component of dual-polarized refiectarrays using the Method of Moments (MoM) is described. It is based on the Levenberg-Marquardt Algorithm (LMA) and it exploits several optimization techniques to accelerate the computations in order to be able to use MoM within acceptable computing times. Since MoM is used to analyze the refiectarray unit cell, it accurately accounts for the crosspolar components of the radiated far field, which can then be optimized in order to reduce its value while preserving the copolar shape. A test case is provided to validate the developed algorithm in which a Local Multipoint Distribution Service (LMDS) pattern is optimized.}, note = {10th European Conference on Antennas and Propagation (EuCAP), Davos, SWITZERLAND, APR 10-15, 2016}, keywords = {}, pubstate = {published}, tppubtype = {inproceedings} } A method for the optimization of the crosspolar component of dual-polarized refiectarrays using the Method of Moments (MoM) is described. It is based on the Levenberg-Marquardt Algorithm (LMA) and it exploits several optimization techniques to accelerate the computations in order to be able to use MoM within acceptable computing times. Since MoM is used to analyze the refiectarray unit cell, it accurately accounts for the crosspolar components of the radiated far field, which can then be optimized in order to reduce its value while preserving the copolar shape. A test case is provided to validate the developed algorithm in which a Local Multipoint Distribution Service (LMDS) pattern is optimized. |
Martinez-de-Rioja, Eduardo; Encinar, Jose A; Florencio, Rafael; Boix, Rafael R Reflectarray in K and Ka Bands with Independent Beams in Each Polarization Artículo en actas 2016 IEEE ANTENNAS AND PROPAGATION SOCIETY INTERNATIONAL SYMPOSIUM, pp. 1199-1200, Inst Elect & Elect Engineers Antennas & Propagat Soc; Inst Elect & Elect Engineers 2016, ISSN: 1522-3965, (IEEE-Antennas-and-Propagation-Society International Symposium, Fajardo, PR, JUN 26-JUL 01, 2016). @inproceedings{MartinezdeRioja2016a, title = {Reflectarray in K and Ka Bands with Independent Beams in Each Polarization}, author = {Eduardo Martinez-de-Rioja and Jose A Encinar and Rafael Florencio and Rafael R Boix}, issn = {1522-3965}, year = {2016}, date = {2016-01-01}, booktitle = {2016 IEEE ANTENNAS AND PROPAGATION SOCIETY INTERNATIONAL SYMPOSIUM}, pages = {1199-1200}, organization = {Inst Elect & Elect Engineers Antennas & Propagat Soc; Inst Elect & Elect Engineers}, series = {IEEE Antennas and Propagation Society International Symposium}, abstract = {This contribution describes the design of a printed reflectarray antenna to operate at 19.7 and 29.5 GHz with independent beams in H and V polarizations. A dual-frequency dual-polarization reflectarray cell, made of two stacked sets of parallel dipoles for each polarization, is proposed. The dipole lengths are adjusted to produce the required phase-shift at each frequency and each polarization. A 1.6-m reflectarray has been designed to produce two closely spaced beams in H and V polarizations. The simulated radiation patterns show a gain of 48.3 dBi at 19.7 GHz and 50.7 dBi at 29.5 GHz, with side-lobe levels close to -25 dB and low cross-polar radiation.}, note = {IEEE-Antennas-and-Propagation-Society International Symposium, Fajardo, PR, JUN 26-JUL 01, 2016}, keywords = {}, pubstate = {published}, tppubtype = {inproceedings} } This contribution describes the design of a printed reflectarray antenna to operate at 19.7 and 29.5 GHz with independent beams in H and V polarizations. A dual-frequency dual-polarization reflectarray cell, made of two stacked sets of parallel dipoles for each polarization, is proposed. The dipole lengths are adjusted to produce the required phase-shift at each frequency and each polarization. A 1.6-m reflectarray has been designed to produce two closely spaced beams in H and V polarizations. The simulated radiation patterns show a gain of 48.3 dBi at 19.7 GHz and 50.7 dBi at 29.5 GHz, with side-lobe levels close to -25 dB and low cross-polar radiation. |
Martinez-de-Rioja, Daniel; Martinez-de-Rioja, Eduardo; Encinar, Jose A Multibeam Reflectarray for Transmit Satellite Antennas in Ka Band Using Beam-Squint Artículo en actas 2016 IEEE ANTENNAS AND PROPAGATION SOCIETY INTERNATIONAL SYMPOSIUM, pp. 1421-1422, Inst Elect & Elect Engineers Antennas & Propagat Soc; Inst Elect & Elect Engineers 2016, ISSN: 1522-3965, (IEEE-Antennas-and-Propagation-Society International Symposium, Fajardo, PR, JUN 26-JUL 01, 2016). @inproceedings{MartinezdeRioja2016b, title = {Multibeam Reflectarray for Transmit Satellite Antennas in Ka Band Using Beam-Squint}, author = {Daniel Martinez-de-Rioja and Eduardo Martinez-de-Rioja and Jose A Encinar}, issn = {1522-3965}, year = {2016}, date = {2016-01-01}, booktitle = {2016 IEEE ANTENNAS AND PROPAGATION SOCIETY INTERNATIONAL SYMPOSIUM}, pages = {1421-1422}, organization = {Inst Elect & Elect Engineers Antennas & Propagat Soc; Inst Elect & Elect Engineers}, series = {IEEE Antennas and Propagation Society International Symposium}, abstract = {This contribution describes a design concept based on beam squint effect in printed reflectarrays that allows to produce multiple contiguous beams at 19.5 and 20 GHz, by discriminating in frequency. A 1.6-m reflectarray has been proposed to produce 10 beams separated 0.5 degree using five feeds with frequency reuse. The simulated radiation patterns show a peak gain better than 47.6 dBi, with side-lobe levels close to -22 dB. The proposed concept can be suitable for multiple spot beam satellites in Ka-band.}, note = {IEEE-Antennas-and-Propagation-Society International Symposium, Fajardo, PR, JUN 26-JUL 01, 2016}, keywords = {}, pubstate = {published}, tppubtype = {inproceedings} } This contribution describes a design concept based on beam squint effect in printed reflectarrays that allows to produce multiple contiguous beams at 19.5 and 20 GHz, by discriminating in frequency. A 1.6-m reflectarray has been proposed to produce 10 beams separated 0.5 degree using five feeds with frequency reuse. The simulated radiation patterns show a peak gain better than 47.6 dBi, with side-lobe levels close to -22 dB. The proposed concept can be suitable for multiple spot beam satellites in Ka-band. |
Prado, Daniel Rodriguez; Campa, Adrian; Arrebola, Manuel; Pino, Marcos R; Encinar, Jose A; Las-Heras, Fernando Design, Manufacture, and Measurement of a Low-Cost Reflectarray for Global Earth Coverage Artículo de revista IEEE ANTENNAS AND WIRELESS PROPAGATION LETTERS, 15 , pp. 1418-1421, 2016, ISSN: 1536-1225. @article{RodriguezPrado2016, title = {Design, Manufacture, and Measurement of a Low-Cost Reflectarray for Global Earth Coverage}, author = {Daniel Rodriguez Prado and Adrian Campa and Manuel Arrebola and Marcos R Pino and Jose A Encinar and Fernando Las-Heras}, doi = {10.1109/LAWP.2015.2511300}, issn = {1536-1225}, year = {2016}, date = {2016-01-01}, journal = {IEEE ANTENNAS AND WIRELESS PROPAGATION LETTERS}, volume = {15}, pages = {1418-1421}, abstract = {In this work, a low-cost reflectarray with isoflux pattern for global Earth coverage is designed, manufactured, and measured at 30 GHz. The isoflux template is mathematically derived for a generic satellite and then particularized for a geostationary orbit. In order to reduce costs, the synthesis and design processes have to be accordingly adapted. First, the most simple unit cell is selected, consisting of a single layer of rectangular patches backed by a ground plane. This cell is not able to provide a 360 phase range, and thus the synthesis algorithm has to be modified to include a phase constraint to match the range provided by the element, ensuring at the same time a smooth variation of the elements in order to obtain a reliable design. This is further ensured by limiting the patch size to a given range during the design process. Finally, the reflectarray is manufactured and measured, showing good agreement with the simulations.}, keywords = {}, pubstate = {published}, tppubtype = {article} } In this work, a low-cost reflectarray with isoflux pattern for global Earth coverage is designed, manufactured, and measured at 30 GHz. The isoflux template is mathematically derived for a generic satellite and then particularized for a geostationary orbit. In order to reduce costs, the synthesis and design processes have to be accordingly adapted. First, the most simple unit cell is selected, consisting of a single layer of rectangular patches backed by a ground plane. This cell is not able to provide a 360 phase range, and thus the synthesis algorithm has to be modified to include a phase constraint to match the range provided by the element, ensuring at the same time a smooth variation of the elements in order to obtain a reliable design. This is further ensured by limiting the patch size to a given range during the design process. Finally, the reflectarray is manufactured and measured, showing good agreement with the simulations. |
Gil, Jose M; Zapata, Juan; Gómez, Rafael; Garcia, Jesus On the higher-order approximations for computational electromagnetics Artículo en actas Oviedo, Spain, 2016. @inproceedings{Gil2016a, title = {On the higher-order approximations for computational electromagnetics}, author = {Jose M Gil and Juan Zapata and Rafael Gómez and Jesus Garcia}, year = {2016}, date = {2016-01-01}, address = {Oviedo, Spain}, keywords = {}, pubstate = {published}, tppubtype = {inproceedings} } |
Rubio, Jesus; Corcoles, Juan; Izquierdo, Juan F; Gomez-Alcala, Rafel; Gil, Jose M Shaped beam synthesis of sparse arrays of coupled elements through a modified Orthogonal Matching Pursuit algorithm and multiple dictionaries Artículo en actas pp. 1–3, IEEE, Davos, 2016, ISBN: 978-8-8907-0186-3. @inproceedings{Rubio2016, title = {Shaped beam synthesis of sparse arrays of coupled elements through a modified Orthogonal Matching Pursuit algorithm and multiple dictionaries}, author = {Jesus Rubio and Juan Corcoles and Juan F Izquierdo and Rafel Gomez-Alcala and Jose M Gil}, doi = {10.1109/EuCAP.2016.7481201}, isbn = {978-8-8907-0186-3}, year = {2016}, date = {2016-01-01}, pages = {1--3}, publisher = {IEEE}, address = {Davos}, abstract = {A method to design sparse arrays based on the Orthogonal Matching Pursuit algorithm and spherical wave expansions is proposed. The Orthogonal Matching Pursuit algorithm is modified in order to take mutual coupling effects into account in the design of sparse arrays. Different Dictionaries are used, going beyond a recently proposed application of the method to array thinning. Further reduction of elements can be achieved at the expense of increasing the computational time in the design process.}, keywords = {}, pubstate = {published}, tppubtype = {inproceedings} } A method to design sparse arrays based on the Orthogonal Matching Pursuit algorithm and spherical wave expansions is proposed. The Orthogonal Matching Pursuit algorithm is modified in order to take mutual coupling effects into account in the design of sparse arrays. Different Dictionaries are used, going beyond a recently proposed application of the method to array thinning. Further reduction of elements can be achieved at the expense of increasing the computational time in the design process. |
Gil, Jose M; Gomez, Rafael; Gonzalez-de-Aza, Miguel A; Garcia, Jesus Loop-star decomposition for any order basis functions with processing of weak and nearly singularities for the surface integral equation Artículo en actas pp. 1–3, IEEE, Davos, 2016, ISBN: 978-8-8907-0186-3. @inproceedings{Gil2016b, title = {Loop-star decomposition for any order basis functions with processing of weak and nearly singularities for the surface integral equation}, author = {Jose M Gil and Rafael Gomez and Miguel A Gonzalez-de-Aza and Jesus Garcia}, doi = {10.1109/EuCAP.2016.7481686}, isbn = {978-8-8907-0186-3}, year = {2016}, date = {2016-01-01}, pages = {1--3}, publisher = {IEEE}, address = {Davos}, abstract = {A procedure to obtain div-conforming elements for the Surface Integral Equation, by rotating some popular curl-conforming bases used in the Finite Elements Method (FEM) is presented. The method maintains the Helmholtz decomposition for surface currents, for any order of bases functions and any curvature order of the domain. Thanks to the current decomposition, a frequency scaling avoids the frequency breakdown. For addressing the problem of the singular term in the integral equation, we use a coordinate transformation to cancel out the singular term. The singularity cancellation is carried out directly on a plane local domain. The procedure is compatible with any order of curvature of the elements and invariant with the order of the bases functions. The coordinate transformation adds a parameter suitable to treat the near-singularities.}, keywords = {}, pubstate = {published}, tppubtype = {inproceedings} } A procedure to obtain div-conforming elements for the Surface Integral Equation, by rotating some popular curl-conforming bases used in the Finite Elements Method (FEM) is presented. The method maintains the Helmholtz decomposition for surface currents, for any order of bases functions and any curvature order of the domain. Thanks to the current decomposition, a frequency scaling avoids the frequency breakdown. For addressing the problem of the singular term in the integral equation, we use a coordinate transformation to cancel out the singular term. The singularity cancellation is carried out directly on a plane local domain. The procedure is compatible with any order of curvature of the elements and invariant with the order of the bases functions. The coordinate transformation adds a parameter suitable to treat the near-singularities. |
Montejo-Garai, Jose R; Saracho-Pantoja, Irene O; Ruiz-Cruz, Jorge A; Rebollar, Jesus M Broadband and High-Purity Ku-Band Circular TE01-Mode Converter Artículo en actas 2016 ASIA-PACIFIC MICROWAVE CONFERENCE (APMC2016), IEEE; MTTS; IEEE Delhi Sect; European Microwave Assoc 2016, ISBN: 978-1-5090-1592-4, (Asia-Pacific Microwave Conference (APMC), New Delhi, INDIA, DEC 05-09, 2016). @inproceedings{MontejoGarai2016, title = {Broadband and High-Purity Ku-Band Circular TE01-Mode Converter}, author = {Jose R Montejo-Garai and Irene O Saracho-Pantoja and Jorge A Ruiz-Cruz and Jesus M Rebollar}, doi = {10.1109/APMC.2016.7931375}, isbn = {978-1-5090-1592-4}, year = {2016}, date = {2016-01-01}, booktitle = {2016 ASIA-PACIFIC MICROWAVE CONFERENCE (APMC2016)}, organization = {IEEE; MTTS; IEEE Delhi Sect; European Microwave Assoc}, series = {Asia Pacific Microwave Conference-Proceedings}, abstract = {This work presents the design of a Ku-band circular high-purity TE01-mode converter with broadband matching response and very low level higher modes. Sidewall iris couplings as well as diverse matching elements in the mode-converting section have been considered during the optimization process to obtain a return-loss level better than 30 dB and higher-order mode attenuation better than 50 dB in a 2 GHz bandwidth centered at 12 GHz (16.7% of fractional bandwidth). In order to verify the feasibility of the milling mechanization of the design and to detect any critical issue, the Additive Manufacturing (AM) technique named Fused Filament Fabrication (FFF) has been used to obtain a proof-of-concept prototype.}, note = {Asia-Pacific Microwave Conference (APMC), New Delhi, INDIA, DEC 05-09, 2016}, keywords = {}, pubstate = {published}, tppubtype = {inproceedings} } This work presents the design of a Ku-band circular high-purity TE01-mode converter with broadband matching response and very low level higher modes. Sidewall iris couplings as well as diverse matching elements in the mode-converting section have been considered during the optimization process to obtain a return-loss level better than 30 dB and higher-order mode attenuation better than 50 dB in a 2 GHz bandwidth centered at 12 GHz (16.7% of fractional bandwidth). In order to verify the feasibility of the milling mechanization of the design and to detect any critical issue, the Additive Manufacturing (AM) technique named Fused Filament Fabrication (FFF) has been used to obtain a proof-of-concept prototype. |
Moran-Lopez, Ana; Corcoles, Juan; Ruiz-Cruz, Jorge A; Montejo-Garai, Jose R; Rebollar, Jesus M Generalized Scattering Matrix of the Discontinuity between an Equilateral Triangular Waveguide and a Rectangular, Circular or Elliptical Waveguide Artículo en actas 2016 ASIA-PACIFIC MICROWAVE CONFERENCE (APMC2016), IEEE; MTTS; IEEE Delhi Sect; European Microwave Assoc 2016, ISBN: 978-1-5090-1592-4, (Asia-Pacific Microwave Conference (APMC), New Delhi, INDIA, DEC 05-09, 2016). @inproceedings{MoranLopez2016, title = {Generalized Scattering Matrix of the Discontinuity between an Equilateral Triangular Waveguide and a Rectangular, Circular or Elliptical Waveguide}, author = {Ana Moran-Lopez and Juan Corcoles and Jorge A Ruiz-Cruz and Jose R Montejo-Garai and Jesus M Rebollar}, doi = {10.1109/APMC.2016.7931283}, isbn = {978-1-5090-1592-4}, year = {2016}, date = {2016-01-01}, booktitle = {2016 ASIA-PACIFIC MICROWAVE CONFERENCE (APMC2016)}, organization = {IEEE; MTTS; IEEE Delhi Sect; European Microwave Assoc}, series = {Asia Pacific Microwave Conference-Proceedings}, abstract = {The full-wave analysis of the discontinuity between an equilateral triangular waveguide and other analytical larger waveguide with rectangular, circular or elliptical cross-section is presented. The equilateral waveguide can be shifted and/or rotated with respect to the other waveguide, providing a great flexibility for the design of microwave components such as transformers, filters or double-polarization components. Furthermore, the presented quasi-analytic formulation, unified for the three cases throughout the use of plane wave series, is very efficient and can be integrated in hybrid solvers for full-wave optimization. The Mode-Matching technique is employed for analyzing the basic discontinuity and the inner cross products between the modes are computed by means of their plane wave representation in the different waveguides. The simulation results are compared with those obtained by other numerical techniques.}, note = {Asia-Pacific Microwave Conference (APMC), New Delhi, INDIA, DEC 05-09, 2016}, keywords = {}, pubstate = {published}, tppubtype = {inproceedings} } The full-wave analysis of the discontinuity between an equilateral triangular waveguide and other analytical larger waveguide with rectangular, circular or elliptical cross-section is presented. The equilateral waveguide can be shifted and/or rotated with respect to the other waveguide, providing a great flexibility for the design of microwave components such as transformers, filters or double-polarization components. Furthermore, the presented quasi-analytic formulation, unified for the three cases throughout the use of plane wave series, is very efficient and can be integrated in hybrid solvers for full-wave optimization. The Mode-Matching technique is employed for analyzing the basic discontinuity and the inner cross products between the modes are computed by means of their plane wave representation in the different waveguides. The simulation results are compared with those obtained by other numerical techniques. |
Leal-Sevillano, Carlos A; Ruiz-Cruz, Jorge A; Montejo-Garai, Jose R; Rebollar, Jesus M A Virtual Lossy Dielectric Model with Composite Boundary Conditions for the Analysis of Substrate Integrated Waveguides Artículo en actas 2016 46TH EUROPEAN MICROWAVE CONFERENCE (EUMC), pp. 162-165, APS 2016, ISSN: 2325-0305, (46th European Microwave Conference (EuMC), London, ENGLAND, OCT 04-06, 2016). @inproceedings{LealSevillano2016a, title = {A Virtual Lossy Dielectric Model with Composite Boundary Conditions for the Analysis of Substrate Integrated Waveguides}, author = {Carlos A Leal-Sevillano and Jorge A Ruiz-Cruz and Jose R Montejo-Garai and Jesus M Rebollar}, doi = {10.1109/EuMC.2016.7824303}, issn = {2325-0305}, year = {2016}, date = {2016-01-01}, booktitle = {2016 46TH EUROPEAN MICROWAVE CONFERENCE (EUMC)}, pages = {162-165}, organization = {APS}, series = {European Microwave Conference}, abstract = {A new model for the characterization of substrate integrated waveguides is presented based on the analysis of a non-homogeneous closed waveguide with composite boundary conditions and a section of virtual lossy dielectric. The performance of the closed waveguide simulates the substrate integrated waveguide, once the parameters of the lossy dielectric section are adjusted (width, dielectric permitivity and magnetic permeability). This simple model gives physical insight into the propagation in the substrate integrated waveguide and it is inspired in the different field regions which appear in the open problem. Another important feature of this model is that it allows the characterization of the open substrate structure, including the radiation loss, with an equivalent closed waveguide, where well-known and efficient full-wave methods can be applied. Thus, this model is suited for the accurate analysis and design of devices in substrate integrated waveguide, as it is shown with different structures. The model is able to predict the radiation loss when the structure has large distance between posts. The agreement between measured results and the simulations are also confirmed with a bandpass filter.}, note = {46th European Microwave Conference (EuMC), London, ENGLAND, OCT 04-06, 2016}, keywords = {}, pubstate = {published}, tppubtype = {inproceedings} } A new model for the characterization of substrate integrated waveguides is presented based on the analysis of a non-homogeneous closed waveguide with composite boundary conditions and a section of virtual lossy dielectric. The performance of the closed waveguide simulates the substrate integrated waveguide, once the parameters of the lossy dielectric section are adjusted (width, dielectric permitivity and magnetic permeability). This simple model gives physical insight into the propagation in the substrate integrated waveguide and it is inspired in the different field regions which appear in the open problem. Another important feature of this model is that it allows the characterization of the open substrate structure, including the radiation loss, with an equivalent closed waveguide, where well-known and efficient full-wave methods can be applied. Thus, this model is suited for the accurate analysis and design of devices in substrate integrated waveguide, as it is shown with different structures. The model is able to predict the radiation loss when the structure has large distance between posts. The agreement between measured results and the simulations are also confirmed with a bandpass filter. |
Polo-Lopez, Lucas; Ruiz-Cruz, Jorge A; Montejo-Garai, Jose R; Rebollar, Jesus M Analysis of Waveguide Discontinuities with Lateral and Transverse Perfect Magnetic Wall Boundary Conditions Artículo en actas 2016 URSI INTERNATIONAL SYMPOSIUM ON ELECTROMAGNETIC THEORY (EMTS), pp. 811-814, URSI, Commiss B 2016, ISSN: 2163-405X, (URSI-Commission-B International Symposium on Electromagnetic Theory (EMTS), Espoo, FINLAND, AUG 14-18, 2016). @inproceedings{PoloLopez2016, title = {Analysis of Waveguide Discontinuities with Lateral and Transverse Perfect Magnetic Wall Boundary Conditions}, author = {Lucas Polo-Lopez and Jorge A Ruiz-Cruz and Jose R Montejo-Garai and Jesus M Rebollar}, doi = {10.1109/URSI-EMTS.2016.7571527}, issn = {2163-405X}, year = {2016}, date = {2016-01-01}, booktitle = {2016 URSI INTERNATIONAL SYMPOSIUM ON ELECTROMAGNETIC THEORY (EMTS)}, pages = {811-814}, organization = {URSI, Commiss B}, series = {URSI International Symposium on Electromagnetic Theory}, abstract = {This contribution presents the analysis of waveguide problems involving general boundary conditions of perfect magnetic wall. This type of boundary condition, when the waveguide device under analysis has physical symmetry, is used very commonly to speed up the computation time in general waveguide solvers by exploiting the symmetries of the excitation. This contribution is focused on extending its use in general problems having this type of boundary condition in the lateral and transverse walls, applying the mode-matching method. The formulation will be applied to classical waveguide devices surrounded by perfect magnetic walls, but also to simulate radiating problems. The simulation results will be compared with those obtained by other numerical techniques (based on different solvers) to test the validity of the presented formulation.}, note = {URSI-Commission-B International Symposium on Electromagnetic Theory (EMTS), Espoo, FINLAND, AUG 14-18, 2016}, keywords = {}, pubstate = {published}, tppubtype = {inproceedings} } This contribution presents the analysis of waveguide problems involving general boundary conditions of perfect magnetic wall. This type of boundary condition, when the waveguide device under analysis has physical symmetry, is used very commonly to speed up the computation time in general waveguide solvers by exploiting the symmetries of the excitation. This contribution is focused on extending its use in general problems having this type of boundary condition in the lateral and transverse walls, applying the mode-matching method. The formulation will be applied to classical waveguide devices surrounded by perfect magnetic walls, but also to simulate radiating problems. The simulation results will be compared with those obtained by other numerical techniques (based on different solvers) to test the validity of the presented formulation. |
Moran-Lopez, Ana; Corcoles, Juan; Ruiz-Cruz, Jorge A; Montejo-Garai, Jose R; Rebollar, Jesus M Electromagnetic Scattering at the Waveguide Step between Equilateral Triangular Waveguides Artículo de revista ADVANCES IN MATHEMATICAL PHYSICS, 2016 , 2016, ISSN: 1687-9120. @article{MoranLopez2016a, title = {Electromagnetic Scattering at the Waveguide Step between Equilateral Triangular Waveguides}, author = {Ana Moran-Lopez and Juan Corcoles and Jorge A Ruiz-Cruz and Jose R Montejo-Garai and Jesus M Rebollar}, doi = {10.1155/2016/2974675}, issn = {1687-9120}, year = {2016}, date = {2016-01-01}, journal = {ADVANCES IN MATHEMATICAL PHYSICS}, volume = {2016}, abstract = {The analysis of the electromagnetic scattering at discontinuities between equilateral triangular waveguides is studied. The complete electromagnetic solution is derived using analytical closed form expressions for the mode spectrum of the equilateral waveguide. The mathematical formulation of the electromagnetic scattering problem is based on the quasi-analytical Mode-Matching method. This method benefits from the electromagnetic field division into symmetries as well as from the plane wave formulation presented for the expressions involved. The unification of the surface integrals used in the method thanks to the plane wave formulation is revealed, leading to expressions that are very well suited for its implementation in an electromagnetic analysis and design code. The obtained results for some cases of interest (building blocks for microwave components for communication systems) are verified using other numerical methods included in a commercial software package, showing the potential of the presented approach based on quasi-analytic expressions.}, keywords = {}, pubstate = {published}, tppubtype = {article} } The analysis of the electromagnetic scattering at discontinuities between equilateral triangular waveguides is studied. The complete electromagnetic solution is derived using analytical closed form expressions for the mode spectrum of the equilateral waveguide. The mathematical formulation of the electromagnetic scattering problem is based on the quasi-analytical Mode-Matching method. This method benefits from the electromagnetic field division into symmetries as well as from the plane wave formulation presented for the expressions involved. The unification of the surface integrals used in the method thanks to the plane wave formulation is revealed, leading to expressions that are very well suited for its implementation in an electromagnetic analysis and design code. The obtained results for some cases of interest (building blocks for microwave components for communication systems) are verified using other numerical methods included in a commercial software package, showing the potential of the presented approach based on quasi-analytic expressions. |
Abdo-Sánchez, E; Martín-Guerrero, T M; Esteban, J; Camacho-Peñalosa, C Short dual-band planar leaky-wave antenna with broadside effect mitigation Artículo de revista IET Microwaves, Antennas and Propagation, 10 (5), pp. 574-578, 2016, ISSN: 1751-8725. @article{AbdoSanchez2016, title = {Short dual-band planar leaky-wave antenna with broadside effect mitigation}, author = {E Abdo-Sánchez and T M Martín-Guerrero and J Esteban and C Camacho-Peñalosa}, doi = {10.1049/iet-map.2015.0741}, issn = {1751-8725}, year = {2016}, date = {2016-01-01}, journal = {IET Microwaves, Antennas and Propagation}, volume = {10}, number = {5}, pages = {574-578}, abstract = {In this contribution, a planar leaky-wave antenna capable of dual-band frequency scanning including broadside is presented. It is based on the complementary strip-slot element, which is a microstrip-fed slot with ultra broad impedance bandwidth, achieved by introducing its complementary stub on the layer of the microstrip. The mitigation of the broadside degradation is accomplished by properly designing the strip-slot and the pitch of the array and by introducing asymmetry (misalignment) in the unit-cell. The resulting structure differs from previous proposals in the broadband element on which it is based, which allows dual-band behaviour and high efficiency with an array of just five elements.}, keywords = {}, pubstate = {published}, tppubtype = {article} } In this contribution, a planar leaky-wave antenna capable of dual-band frequency scanning including broadside is presented. It is based on the complementary strip-slot element, which is a microstrip-fed slot with ultra broad impedance bandwidth, achieved by introducing its complementary stub on the layer of the microstrip. The mitigation of the broadside degradation is accomplished by properly designing the strip-slot and the pitch of the array and by introducing asymmetry (misalignment) in the unit-cell. The resulting structure differs from previous proposals in the broadband element on which it is based, which allows dual-band behaviour and high efficiency with an array of just five elements. |
2015 |
Echeveste, Jose Ignacio; Gonzalez-de-Aza, Miguel A; Zapata, Juan Array Pattern Synthesis of Real Antennas Using the Infinite-Array Approach and Linear Programming Artículo de revista IEEE TRANSACTIONS ON ANTENNAS AND PROPAGATION, 63 (12), pp. 5417-5424, 2015, ISSN: 0018-926X. @article{IgnacioEcheveste2015, title = {Array Pattern Synthesis of Real Antennas Using the Infinite-Array Approach and Linear Programming}, author = {Jose Ignacio Echeveste and Miguel A Gonzalez-de-Aza and Juan Zapata}, doi = {10.1109/TAP.2015.2496106}, issn = {0018-926X}, year = {2015}, date = {2015-12-01}, journal = {IEEE TRANSACTIONS ON ANTENNAS AND PROPAGATION}, volume = {63}, number = {12}, pages = {5417-5424}, abstract = {This work proposes an efficient optimization methodology of antenna array excitations accounting for the effects of mutual couplings and real radiating patterns of array elements with complex geometry. The method is formulated as a linear programming problem providing multibeam patterns with specified beamwidths, constraints on sidelobe and cross-polar levels, and null pointing directions. A matrix formulation is used to integrate the optimization procedure and a finite-array analysis based on the infinite-array approach, in which the periodic radiating element is characterized by a full-wave and hybrid procedure, combining the domain decomposition technique, the finite-element method, and modal analysis. Numerical examples of arrays of open-ended waveguides, microstrip antennas, and dielectric resonator antennas are presented.}, keywords = {}, pubstate = {published}, tppubtype = {article} } This work proposes an efficient optimization methodology of antenna array excitations accounting for the effects of mutual couplings and real radiating patterns of array elements with complex geometry. The method is formulated as a linear programming problem providing multibeam patterns with specified beamwidths, constraints on sidelobe and cross-polar levels, and null pointing directions. A matrix formulation is used to integrate the optimization procedure and a finite-array analysis based on the infinite-array approach, in which the periodic radiating element is characterized by a full-wave and hybrid procedure, combining the domain decomposition technique, the finite-element method, and modal analysis. Numerical examples of arrays of open-ended waveguides, microstrip antennas, and dielectric resonator antennas are presented. |
Perez-Palomino, Gerardo; Barba, Mariano; Encinar, Jose A; Cahill, Robert; Dickie, Raymond; Baine, Paul; Bain, Michael Design and Demonstration of an Electronically Scanned Reflectarray Antenna at 100 GHz Using Multiresonant Cells Based on Liquid Crystals Artículo de revista IEEE TRANSACTIONS ON ANTENNAS AND PROPAGATION, 63 (8), pp. 3722-3727, 2015, ISSN: 0018-926X. @article{PerezPalomino2015, title = {Design and Demonstration of an Electronically Scanned Reflectarray Antenna at 100 GHz Using Multiresonant Cells Based on Liquid Crystals}, author = {Gerardo Perez-Palomino and Mariano Barba and Jose A Encinar and Robert Cahill and Raymond Dickie and Paul Baine and Michael Bain}, doi = {10.1109/TAP.2015.2434421}, issn = {0018-926X}, year = {2015}, date = {2015-08-01}, journal = {IEEE TRANSACTIONS ON ANTENNAS AND PROPAGATION}, volume = {63}, number = {8}, pages = {3722-3727}, abstract = {The design, fabrication, and measured results are presented for a reconfigurable reflectarray antenna based on liquid crystals (LCs) which operates above 100 GHz. The antenna has been designed to provide beam scanning capabilities over a wide angular range, a large bandwidth, and reduced side-lobe level (SLL). Measured radiation patterns are in good agreement with simulations, and show that the antenna generates an electronically steerable beam in one plane over an angular range of 55 degrees in the frequency band from 96 to 104 GHz. The SLL is lower than -13 dB for all the scan angles and -18 dB is obtained over 16% of the scan range. The measured performance is significantly better than previously published results for this class of electronically tunable antenna, and moreover, verifies the accuracy of the proposed procedure for LC modeling and antenna design.}, keywords = {}, pubstate = {published}, tppubtype = {article} } The design, fabrication, and measured results are presented for a reconfigurable reflectarray antenna based on liquid crystals (LCs) which operates above 100 GHz. The antenna has been designed to provide beam scanning capabilities over a wide angular range, a large bandwidth, and reduced side-lobe level (SLL). Measured radiation patterns are in good agreement with simulations, and show that the antenna generates an electronically steerable beam in one plane over an angular range of 55 degrees in the frequency band from 96 to 104 GHz. The SLL is lower than -13 dB for all the scan angles and -18 dB is obtained over 16% of the scan range. The measured performance is significantly better than previously published results for this class of electronically tunable antenna, and moreover, verifies the accuracy of the proposed procedure for LC modeling and antenna design. |
Abdo-Sánchez, E; Martín-Guerrero, T M; Camacho-Peñalosa, C; Esteban, J A self-diplexing dual-band planar array for GNSS applications Artículo en actas 2015 IEEE International Symposium on Antennas and Propagation USNC/URSI National Radio Science Meeting, pp. 1874-1875, Vancouver (Canada), 2015, ISSN: 1522-3965, (ISSN: 1522-3965). @inproceedings{AbdoSanchez2015b, title = {A self-diplexing dual-band planar array for GNSS applications}, author = {E Abdo-Sánchez and T M Martín-Guerrero and C Camacho-Peñalosa and J Esteban}, doi = {10.1109/APS.2015.7305326}, issn = {1522-3965}, year = {2015}, date = {2015-07-01}, booktitle = {2015 IEEE International Symposium on Antennas and Propagation USNC/URSI National Radio Science Meeting}, pages = {1874-1875}, address = {Vancouver (Canada)}, abstract = {A planar dual-band sequentially-rotated array is proposed to cover the radionavigation bands at 1.19 and 1.57 GHz. The antenna consists of a two-port ring microstrip line that series feeds four radiating elements. The basic radiator is the so-called complementary strip-slot, a microstrip-fed slot that has its complementary stub superimposed to it on the microstrip layer, in order to cancel the slot resonant behaviour and provide ultra broad impedance matching. Thanks to this element feature, the antenna can cover the two bands and diplex them into the two ports without the need of additional passive or active components. The detailed design and results of the reflection coefficient, axial ratio and radiation patterns are provided, which confirm the good performance of this simple antenna.}, note = {ISSN: 1522-3965}, keywords = {}, pubstate = {published}, tppubtype = {inproceedings} } A planar dual-band sequentially-rotated array is proposed to cover the radionavigation bands at 1.19 and 1.57 GHz. The antenna consists of a two-port ring microstrip line that series feeds four radiating elements. The basic radiator is the so-called complementary strip-slot, a microstrip-fed slot that has its complementary stub superimposed to it on the microstrip layer, in order to cancel the slot resonant behaviour and provide ultra broad impedance matching. Thanks to this element feature, the antenna can cover the two bands and diplex them into the two ports without the need of additional passive or active components. The detailed design and results of the reflection coefficient, axial ratio and radiation patterns are provided, which confirm the good performance of this simple antenna. |
Florencio, Rafael; Boix, Rafael R; Encinar, Jose A Fast and Accurate MoM Analysis of Periodic Arrays of Multilayered Stacked Rectangular Patches With Application to the Design of Reflectarray Antennas Artículo de revista IEEE TRANSACTIONS ON ANTENNAS AND PROPAGATION, 63 (6), pp. 2558-2571, 2015, ISSN: 0018-926X. @article{Florencio2015, title = {Fast and Accurate MoM Analysis of Periodic Arrays of Multilayered Stacked Rectangular Patches With Application to the Design of Reflectarray Antennas}, author = {Rafael Florencio and Rafael R Boix and Jose A Encinar}, doi = {10.1109/TAP.2015.2416753}, issn = {0018-926X}, year = {2015}, date = {2015-06-01}, journal = {IEEE TRANSACTIONS ON ANTENNAS AND PROPAGATION}, volume = {63}, number = {6}, pages = {2558-2571}, abstract = {The scattering of plane waves by periodic arrays of stacked rectangular patches in multilayered substrates is a problem that has to be solved many times when designing reflectarray antennas made of those patches under the local periodicity assumption. The solution to the periodic multilayered problem has been traditionally carried out by means of the Galerkin's version of the method of moments (MoM) in the spectral domain. This approach involves the computation of double infinite summations, and whereas some of these summations converge very fast, some other converge very slowly. In this paper, the slowly convergent summations are computed by making use of an enhanced mixed potential integral equation (MPIE) formulation of the MoM in the spatial domain. This enhanced formulation is based on the interpolation of the multilayered periodic Green's functions, and on the efficient computation of the four-dimensional (4-D) integrals leading to the MoM matrix entries. Both the novel hybrid spectral-spatial MoM code and the standard spectral domain MoM code have been used for the design of a contoured beam reflectarray antenna. It has been verified that the spectral-spatial MoM code requires CPU times that are typically 30 times smaller than those required by the pure spectral domain MoM code.}, keywords = {}, pubstate = {published}, tppubtype = {article} } The scattering of plane waves by periodic arrays of stacked rectangular patches in multilayered substrates is a problem that has to be solved many times when designing reflectarray antennas made of those patches under the local periodicity assumption. The solution to the periodic multilayered problem has been traditionally carried out by means of the Galerkin's version of the method of moments (MoM) in the spectral domain. This approach involves the computation of double infinite summations, and whereas some of these summations converge very fast, some other converge very slowly. In this paper, the slowly convergent summations are computed by making use of an enhanced mixed potential integral equation (MPIE) formulation of the MoM in the spatial domain. This enhanced formulation is based on the interpolation of the multilayered periodic Green's functions, and on the efficient computation of the four-dimensional (4-D) integrals leading to the MoM matrix entries. Both the novel hybrid spectral-spatial MoM code and the standard spectral domain MoM code have been used for the design of a contoured beam reflectarray antenna. It has been verified that the spectral-spatial MoM code requires CPU times that are typically 30 times smaller than those required by the pure spectral domain MoM code. |
Abdo-Sánchez, E; Martín-Guerrero, T M; Esteban, J; Camacho-Peñalosa, C On the phase response and radiation efficiency of the complementary strip-slot as an array element Artículo en actas 2015 9th European Conference on Antennas and Propagation (EuCAP), pp. 1-4, Lisbon (Portugal), 2015, ISSN: 2164-3342, (ISSN: 2164-3342). @inproceedings{AbdoSanchez2015c, title = {On the phase response and radiation efficiency of the complementary strip-slot as an array element}, author = {E Abdo-Sánchez and T M Martín-Guerrero and J Esteban and C Camacho-Peñalosa}, issn = {2164-3342}, year = {2015}, date = {2015-05-01}, booktitle = {2015 9th European Conference on Antennas and Propagation (EuCAP)}, pages = {1-4}, address = {Lisbon (Portugal)}, abstract = {The complementary strip-slot element is a broadly-matched microstrip radiator that has been used to design innovative series-fed arrays. It consists of a microstrip series-fed slot that have its complementary stub on the layer of the microstrip and aligned to the slot. In this contribution, the influence of the strip and slot geometry on its performance is studied through the analysis of four different designs. The obtained results highlight the possibility of controlling the radiation efficiency or the phase response, without compromising the broad matching. Therefore, potential series-fed arrays built with this element can exploit this feature to set the magnitude and phase of the excitations with certain flexibility.}, note = {ISSN: 2164-3342}, keywords = {}, pubstate = {published}, tppubtype = {inproceedings} } The complementary strip-slot element is a broadly-matched microstrip radiator that has been used to design innovative series-fed arrays. It consists of a microstrip series-fed slot that have its complementary stub on the layer of the microstrip and aligned to the slot. In this contribution, the influence of the strip and slot geometry on its performance is studied through the analysis of four different designs. The obtained results highlight the possibility of controlling the radiation efficiency or the phase response, without compromising the broad matching. Therefore, potential series-fed arrays built with this element can exploit this feature to set the magnitude and phase of the excitations with certain flexibility. |
Florencio, Rafael; Encinar, Jose A; Boix, Rafael R; Losada, Vicente; Toso, Giovanni Reflectarray Antennas for Dual Polarization and Broadband Telecom Satellite Applications Artículo de revista IEEE TRANSACTIONS ON ANTENNAS AND PROPAGATION, 63 (4, 1, SI), pp. 1234-1246, 2015, ISSN: 0018-926X. @article{Florencio2015a, title = {Reflectarray Antennas for Dual Polarization and Broadband Telecom Satellite Applications}, author = {Rafael Florencio and Jose A Encinar and Rafael R Boix and Vicente Losada and Giovanni Toso}, doi = {10.1109/TAP.2015.2391279}, issn = {0018-926X}, year = {2015}, date = {2015-04-01}, journal = {IEEE TRANSACTIONS ON ANTENNAS AND PROPAGATION}, volume = {63}, number = {4, 1, SI}, pages = {1234-1246}, abstract = {A reflectarray antenna with improved performance is proposed to operate in dual-polarization and transmit-receive frequencies in Ku-band for broadcast satellite applications. The reflectarray element contains two orthogonal sets of four coplanar parallel dipoles printed on two surfaces, each set combining lateral and broadside coupling. A 40-cm prototype has been designed, manufactured, and tested. The lengths of the coupled dipoles in the reflectarray cells have been optimized to produce a collimated beam in dual polarization in the transmit and receive bands. The measured radiation patterns confirm the high performance of the antenna in terms of bandwidth (27%), low losses, and low levels of cross polarization. Some preliminary simulations at 11.95 GHz for a 1.2-m antenna with South American coverage are presented to show the potential of the proposed antenna for spaceborne antennas in Ku-band.}, keywords = {}, pubstate = {published}, tppubtype = {article} } A reflectarray antenna with improved performance is proposed to operate in dual-polarization and transmit-receive frequencies in Ku-band for broadcast satellite applications. The reflectarray element contains two orthogonal sets of four coplanar parallel dipoles printed on two surfaces, each set combining lateral and broadside coupling. A 40-cm prototype has been designed, manufactured, and tested. The lengths of the coupled dipoles in the reflectarray cells have been optimized to produce a collimated beam in dual polarization in the transmit and receive bands. The measured radiation patterns confirm the high performance of the antenna in terms of bandwidth (27%), low losses, and low levels of cross polarization. Some preliminary simulations at 11.95 GHz for a 1.2-m antenna with South American coverage are presented to show the potential of the proposed antenna for spaceborne antennas in Ku-band. |
Montori, Simone; Cacciamani, Fabrizio; Gatti, Roberto Vincenti; Sorrentino, Roberto; Arista, Guido; Tienda, Carolina; Encinar, Jose A; Toso, Giovanni A Transportable Reflectarray Antenna for Satellite Ku-band Emergency Communications Artículo de revista IEEE TRANSACTIONS ON ANTENNAS AND PROPAGATION, 63 (4, 1, SI), pp. 1393-1407, 2015, ISSN: 0018-926X. @article{Montori2015, title = {A Transportable Reflectarray Antenna for Satellite Ku-band Emergency Communications}, author = {Simone Montori and Fabrizio Cacciamani and Roberto Vincenti Gatti and Roberto Sorrentino and Guido Arista and Carolina Tienda and Jose A Encinar and Giovanni Toso}, doi = {10.1109/TAP.2015.2398128}, issn = {0018-926X}, year = {2015}, date = {2015-04-01}, journal = {IEEE TRANSACTIONS ON ANTENNAS AND PROPAGATION}, volume = {63}, number = {4, 1, SI}, pages = {1393-1407}, abstract = {The design of a Ku-band reconfigurable reflectarray antenna for emergency satellite communications is presented. Bidirectional high data rate satellite links are needed in emergency conditions where other telecommunication infrastructures are not available. In order to operate in this type of scenario, an antenna should be deployable, transportable, and easily repointable. The need of an automatic and fast satellite location and pointing system leads to a completely electronic reconfigurable antenna. The operative bandwidth is from 10.7 to 12.5 GHz for reception and from 14 up to 14.5 GHz for transmission (30% of relative bandwidth). The selected antenna architecture is based on a dual reflectarray system comprising a passive subreflectarray and an active main reflectarray made of reconfigurable 1-bit elementary cells based on PIN diodes.}, keywords = {}, pubstate = {published}, tppubtype = {article} } The design of a Ku-band reconfigurable reflectarray antenna for emergency satellite communications is presented. Bidirectional high data rate satellite links are needed in emergency conditions where other telecommunication infrastructures are not available. In order to operate in this type of scenario, an antenna should be deployable, transportable, and easily repointable. The need of an automatic and fast satellite location and pointing system leads to a completely electronic reconfigurable antenna. The operative bandwidth is from 10.7 to 12.5 GHz for reception and from 14 up to 14.5 GHz for transmission (30% of relative bandwidth). The selected antenna architecture is based on a dual reflectarray system comprising a passive subreflectarray and an active main reflectarray made of reconfigurable 1-bit elementary cells based on PIN diodes. |
Nematollahi, Hoda; Laurin, Jean-Jacques; Page, J E; Encinar, Jose A Design of Broadband Transmitarray Unit Cells With Comparative Study of Different Numbers of Layers Artículo de revista IEEE TRANSACTIONS ON ANTENNAS AND PROPAGATION, 63 (4, 1, SI), pp. 1473-1481, 2015, ISSN: 0018-926X. @article{Nematollahi2015, title = {Design of Broadband Transmitarray Unit Cells With Comparative Study of Different Numbers of Layers}, author = {Hoda Nematollahi and Jean-Jacques Laurin and J E Page and Jose A Encinar}, doi = {10.1109/TAP.2015.2402285}, issn = {0018-926X}, year = {2015}, date = {2015-04-01}, journal = {IEEE TRANSACTIONS ON ANTENNAS AND PROPAGATION}, volume = {63}, number = {4, 1, SI}, pages = {1473-1481}, abstract = {A generalized methodology to design low-profile transmitarray (TA) antennas made of several stacked layers with nonresonant printed phasing elements is presented. A study of the unit cell bandwidth, phase-shift range and tolerances has been conducted considering different numbers of layers. A structure with three metalized layers with capacitive and inductive elements enabling a phase range of nearly 360 degrees and low insertion loss is introduced. A study of the four-layer structure shows improvement in the performance of the unit cells in terms of bandwidth from 2% to more than 20% and a complete phase coverage. Implementations on a flexible substrate of TAs with progressive phase shift operating at 19 GHz are used for validation.}, keywords = {}, pubstate = {published}, tppubtype = {article} } A generalized methodology to design low-profile transmitarray (TA) antennas made of several stacked layers with nonresonant printed phasing elements is presented. A study of the unit cell bandwidth, phase-shift range and tolerances has been conducted considering different numbers of layers. A structure with three metalized layers with capacitive and inductive elements enabling a phase range of nearly 360 degrees and low insertion loss is introduced. A study of the four-layer structure shows improvement in the performance of the unit cells in terms of bandwidth from 2% to more than 20% and a complete phase coverage. Implementations on a flexible substrate of TAs with progressive phase shift operating at 19 GHz are used for validation. |
Carrasco, Eduardo; Tamagnone, M; Mosig, J R; Low, T; Perruisseau-Carrier, J Gate-controlled mid-infrared light bending with aperiodic graphene nanoribbons array Artículo de revista NANOTECHNOLOGY, 26 (13), 2015, ISSN: 0957-4484. @article{ISI:000350890700002, title = {Gate-controlled mid-infrared light bending with aperiodic graphene nanoribbons array}, author = {Eduardo Carrasco and M Tamagnone and J R Mosig and T Low and J Perruisseau-Carrier}, doi = {10.1088/0957-4484/26/13/134002}, issn = {0957-4484}, year = {2015}, date = {2015-03-01}, journal = {NANOTECHNOLOGY}, volume = {26}, number = {13}, abstract = {Graphene plasmonic nanostructures enable subwavelength confinement of electromagnetic energy from the mid-infrared down to the terahertz frequencies. By exploiting the spectrally varying light scattering phase at the vicinity of the resonant frequency of the plasmonic nanostructure, it is possible to control the angle of reflection of an incoming light beam. We demonstrate, through full-wave electromagnetic simulations based on Maxwell equations, the electrical control of the angle of reflection of a mid-infrared light beam by using an aperiodic array of graphene nanoribbons, whose widths are engineered to produce a spatially varying reflection phase profile that allows for the construction of a far-field collimated beam towards a predefined direction.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Graphene plasmonic nanostructures enable subwavelength confinement of electromagnetic energy from the mid-infrared down to the terahertz frequencies. By exploiting the spectrally varying light scattering phase at the vicinity of the resonant frequency of the plasmonic nanostructure, it is possible to control the angle of reflection of an incoming light beam. We demonstrate, through full-wave electromagnetic simulations based on Maxwell equations, the electrical control of the angle of reflection of a mid-infrared light beam by using an aperiodic array of graphene nanoribbons, whose widths are engineered to produce a spatially varying reflection phase profile that allows for the construction of a far-field collimated beam towards a predefined direction. |
Gil, Jose M; Zapata, Juan; Gomez, Rafael; Gonzalez-de-Aza, Miguel A; Rubio, Jesus; Garcia, Jesus Rotation of curl-conforming elements for a frequency stable application to the Surface Integral Equation Artículo en actas 2015 USNC-URSI RADIO SCIENCE MEETING (JOINT WITH AP-S SYMPOSIUM) PROCEEDINGS, pp. 125, Inst Elect Elect Engineers; IEEE Antennas Propagat Soc; IEEE; URSI 2015, ISSN: 2572-3804, (USNC-URSI Radio Science Meeting (Joint with AP-S Symposium) Proceedings, Vancouver, CANADA, JUL 19-19, 2015). @inproceedings{Gil2015, title = {Rotation of curl-conforming elements for a frequency stable application to the Surface Integral Equation}, author = {Jose M Gil and Juan Zapata and Rafael Gomez and Miguel A Gonzalez-de-Aza and Jesus Rubio and Jesus Garcia}, issn = {2572-3804}, year = {2015}, date = {2015-01-01}, booktitle = {2015 USNC-URSI RADIO SCIENCE MEETING (JOINT WITH AP-S SYMPOSIUM) PROCEEDINGS}, pages = {125}, organization = {Inst Elect Elect Engineers; IEEE Antennas Propagat Soc; IEEE; URSI}, series = {USNC-URSI Radio Science Meeting - Joint with AP-S SYMPOSIUM}, note = {USNC-URSI Radio Science Meeting (Joint with AP-S Symposium) Proceedings, Vancouver, CANADA, JUL 19-19, 2015}, keywords = {}, pubstate = {published}, tppubtype = {inproceedings} } |
Florencio, Rafael; Boix, Rafael R; Encinar, Jose A Enhanced Integral Equation Analysis of Multilayered Periodic Structures Useful for the Design of Reflectarray Antennas Artículo en actas PROCEEDINGS OF THE 2015 INTERNATIONAL CONFERENCE ON ELECTROMAGNETICS IN ADVANCED APPLICATIONS (ICEAA), pp. 86-89, Politecnico Torino; IEIIT CNR; Int Union Radio Sci; IEEE Antennas & Propagat Soc; IEEE Italy Sect; IEEE N Italy AP ED MTT Chapter; Ist Superiore Mario Boella, Tecnologie Informazione Telecomunicazione; Torino Wireless Fdn; IEEE Antenna & Propagat Soc 2015, ISBN: 978-1-4799-7806-9, (International Conference on Electromagnetics in Advanced Applications / IEEE-APS Topical Conference on Antennas and Propagation in Wireless Communications, Torino, ITALY, SEP 07-11, 2015). @inproceedings{Florencio2015b, title = {Enhanced Integral Equation Analysis of Multilayered Periodic Structures Useful for the Design of Reflectarray Antennas}, author = {Rafael Florencio and Rafael R Boix and Jose A Encinar}, isbn = {978-1-4799-7806-9}, year = {2015}, date = {2015-01-01}, booktitle = {PROCEEDINGS OF THE 2015 INTERNATIONAL CONFERENCE ON ELECTROMAGNETICS IN ADVANCED APPLICATIONS (ICEAA)}, pages = {86-89}, organization = {Politecnico Torino; IEIIT CNR; Int Union Radio Sci; IEEE Antennas & Propagat Soc; IEEE Italy Sect; IEEE N Italy AP ED MTT Chapter; Ist Superiore Mario Boella, Tecnologie Informazione Telecomunicazione; Torino Wireless Fdn; IEEE Antenna & Propagat Soc}, abstract = {When reflectarray antennas are designed under the local periodicity assumption, the problem of the scattering of plane waves by multilayered periodic structures has to be solved many times. The Method of Moments (MoM) in the spectral domain is the numerical technique usually employed for the analysis of these multilayered structures. Unfortunately, it is not computationally efficient since it requires the determination of slowly convergent double infinite summations. In this paper the Mixed Potential Integral Equation (MPIE) formulation of the MoM in the spatial domain is invoked to transform the slowly convergent summations into singular finite double integrals that can be efficiently computed. The novel MoM approach in the spatial domain has been found to be between one and two orders of magnitude faster than the traditional spectral domain MoM both in the analysis of multilayered periodic structures, and in the design of reflectarray antennas with cell characterization based on the local periodicity assumption.}, note = {International Conference on Electromagnetics in Advanced Applications / IEEE-APS Topical Conference on Antennas and Propagation in Wireless Communications, Torino, ITALY, SEP 07-11, 2015}, keywords = {}, pubstate = {published}, tppubtype = {inproceedings} } When reflectarray antennas are designed under the local periodicity assumption, the problem of the scattering of plane waves by multilayered periodic structures has to be solved many times. The Method of Moments (MoM) in the spectral domain is the numerical technique usually employed for the analysis of these multilayered structures. Unfortunately, it is not computationally efficient since it requires the determination of slowly convergent double infinite summations. In this paper the Mixed Potential Integral Equation (MPIE) formulation of the MoM in the spatial domain is invoked to transform the slowly convergent summations into singular finite double integrals that can be efficiently computed. The novel MoM approach in the spatial domain has been found to be between one and two orders of magnitude faster than the traditional spectral domain MoM both in the analysis of multilayered periodic structures, and in the design of reflectarray antennas with cell characterization based on the local periodicity assumption. |
Ruiz-Cruz, Jorge A; Montejo-Garai, Jose R; Leal-Sevillano, Carlos A; Rebollar, Jesus M Development of Folded Dual-Polarization Dividers for Broadband Ortho-Mode Transducers Artículo en actas {Hong, W; Zhu, X; Yang, G; Song, Z; Meng, F} (Ed.): 2015 ASIA-PACIFIC MICROWAVE CONFERENCE (APMC), VOLS 1-3, SE Univ; Nanjing Univ Sci & Technol; Chinese Inst Elect; IEEE Microwave Theory & Tech Soc; European Microwave Assoc; IEEE Antennas & Propagat Soc; Sci & Technol Antenna & Microwave Lab; State Key Lab Millimeter Waves; Jiangsu Inst Elect; IEEE AP MTT EMC Joint Nanjing Chapter; Journal Microwaves 2015, ISBN: 978-1-4799-8767-2, (Asia-Pacific Microwave Conference (APMC), Nanjing, PEOPLES R CHINA, DEC 06-09, 2015). @inproceedings{RuizCruz2015, title = {Development of Folded Dual-Polarization Dividers for Broadband Ortho-Mode Transducers}, author = {Jorge A Ruiz-Cruz and Jose R Montejo-Garai and Carlos A Leal-Sevillano and Jesus M Rebollar}, editor = {W {Hong and X Zhu and G Yang and Z Song and F} Meng}, doi = {10.1109/APMC.2015.7413067}, isbn = {978-1-4799-8767-2}, year = {2015}, date = {2015-01-01}, booktitle = {2015 ASIA-PACIFIC MICROWAVE CONFERENCE (APMC), VOLS 1-3}, organization = {SE Univ; Nanjing Univ Sci & Technol; Chinese Inst Elect; IEEE Microwave Theory & Tech Soc; European Microwave Assoc; IEEE Antennas & Propagat Soc; Sci & Technol Antenna & Microwave Lab; State Key Lab Millimeter Waves; Jiangsu Inst Elect; IEEE AP MTT EMC Joint Nanjing Chapter; Journal Microwaves}, series = {Asia Pacific Microwave Conference-Proceedings}, abstract = {A waveguide divider with folded lateral arms is presented for separating dual orthogonal linear polarizations in broadband ortho-mode transducers. The structure is based on a well-known double symmetry junction, where the metallic pins have been eliminated and the lateral outputs have been folded to achieve a combined effect: matching for the vertical polarization and a very significant size reduction. In addition, since the path for the lateral branches has been reduced, the insertion losses for the different polarizations are balanced. The isolation between orthogonal polarizations is kept because of the double-symmetry of the junction. From the mechanical point of view, the proposed junction allows a more simple manufacture and assembly of the ortho-mode transducer parts, which has been shown with a Ku-band design, covering the full Ku-band from 12.6 to 18.25 GHz. The experimental prototype has demonstrated a measured return loss better than 28 dB in the design band and insertion loss smaller than 0.15 dB for both polarizations.}, note = {Asia-Pacific Microwave Conference (APMC), Nanjing, PEOPLES R CHINA, DEC 06-09, 2015}, keywords = {}, pubstate = {published}, tppubtype = {inproceedings} } A waveguide divider with folded lateral arms is presented for separating dual orthogonal linear polarizations in broadband ortho-mode transducers. The structure is based on a well-known double symmetry junction, where the metallic pins have been eliminated and the lateral outputs have been folded to achieve a combined effect: matching for the vertical polarization and a very significant size reduction. In addition, since the path for the lateral branches has been reduced, the insertion losses for the different polarizations are balanced. The isolation between orthogonal polarizations is kept because of the double-symmetry of the junction. From the mechanical point of view, the proposed junction allows a more simple manufacture and assembly of the ortho-mode transducer parts, which has been shown with a Ku-band design, covering the full Ku-band from 12.6 to 18.25 GHz. The experimental prototype has demonstrated a measured return loss better than 28 dB in the design band and insertion loss smaller than 0.15 dB for both polarizations. |
Montejo-Garai, Jose R; Saracho-Pantoja, Irene O; Leal-Sevillano, Carlos A; Ruiz-Cruz, Jorge A; Rebollar, Jesus M Design of Microwave Waveguide Devices for Space and Ground Application Implemented by Additive Manufacturing Artículo en actas PROCEEDINGS OF THE 2015 INTERNATIONAL CONFERENCE ON ELECTROMAGNETICS IN ADVANCED APPLICATIONS (ICEAA), pp. 325-328, Politecnico Torino; IEIIT CNR; Int Union Radio Sci; IEEE Antennas & Propagat Soc; IEEE Italy Sect; IEEE N Italy AP ED MTT Chapter; Ist Superiore Mario Boella, Tecnologie Informazione Telecomunicazione; Torino Wireless Fdn; IEEE Antenna & Propagat Soc 2015, ISBN: 978-1-4799-7806-9, (International Conference on Electromagnetics in Advanced Applications / IEEE-APS Topical Conference on Antennas and Propagation in Wireless Communications, Torino, ITALY, SEP 07-11, 2015). @inproceedings{MontejoGarai2015, title = {Design of Microwave Waveguide Devices for Space and Ground Application Implemented by Additive Manufacturing}, author = {Jose R Montejo-Garai and Irene O Saracho-Pantoja and Carlos A Leal-Sevillano and Jorge A Ruiz-Cruz and Jesus M Rebollar}, doi = {10.1109/ICEAA.2015.7297128}, isbn = {978-1-4799-7806-9}, year = {2015}, date = {2015-01-01}, booktitle = {PROCEEDINGS OF THE 2015 INTERNATIONAL CONFERENCE ON ELECTROMAGNETICS IN ADVANCED APPLICATIONS (ICEAA)}, pages = {325-328}, organization = {Politecnico Torino; IEIIT CNR; Int Union Radio Sci; IEEE Antennas & Propagat Soc; IEEE Italy Sect; IEEE N Italy AP ED MTT Chapter; Ist Superiore Mario Boella, Tecnologie Informazione Telecomunicazione; Torino Wireless Fdn; IEEE Antenna & Propagat Soc}, abstract = {This paper presents the application of the low cost additive manufacturing technique named fused filament fabrication (FFF) to implement waveguide devices. In addition to the reduced price, it also has the added benefit of rapid prototyping, allowing the designer to modify the geometry swiftly. Otherwise this kind of manufacture opens the way to experiment with shapes until now unachievable by traditional subtractive techniques. In order to demonstrate its feasibility, the experimental results of three filters with low-pass, high-pass, and band-pass responses respectively, designed in Ku band with usual specifications in satellite communication systems have been designed, printed, metallized and measured. In the conclusion, the advantages and limitations are highlighted, with special attention dedicated to the metallization process, since it is the bottleneck of the process.}, note = {International Conference on Electromagnetics in Advanced Applications / IEEE-APS Topical Conference on Antennas and Propagation in Wireless Communications, Torino, ITALY, SEP 07-11, 2015}, keywords = {}, pubstate = {published}, tppubtype = {inproceedings} } This paper presents the application of the low cost additive manufacturing technique named fused filament fabrication (FFF) to implement waveguide devices. In addition to the reduced price, it also has the added benefit of rapid prototyping, allowing the designer to modify the geometry swiftly. Otherwise this kind of manufacture opens the way to experiment with shapes until now unachievable by traditional subtractive techniques. In order to demonstrate its feasibility, the experimental results of three filters with low-pass, high-pass, and band-pass responses respectively, designed in Ku band with usual specifications in satellite communication systems have been designed, printed, metallized and measured. In the conclusion, the advantages and limitations are highlighted, with special attention dedicated to the metallization process, since it is the bottleneck of the process. |
Leal-Sevillano, Carlos A; Ruiz-Cruz, Jorge A; Montejo-Garai, Jose R; Rebollar, Jesus M Wide-Band Compact Antenna Feed for Multi-Beam Satellite Communications Artículo en actas 2015 9TH EUROPEAN CONFERENCE ON ANTENNAS AND PROPAGATION (EUCAP), 2015, ISBN: 978-8-8907-0185-6, (9th European Conference on Antennas and Propagation EuCAP, Lisbon, PORTUGAL, MAY 13-17, 2015). @inproceedings{LealSevillano2015, title = {Wide-Band Compact Antenna Feed for Multi-Beam Satellite Communications}, author = {Carlos A Leal-Sevillano and Jorge A Ruiz-Cruz and Jose R Montejo-Garai and Jesus M Rebollar}, isbn = {978-8-8907-0185-6}, year = {2015}, date = {2015-01-01}, booktitle = {2015 9TH EUROPEAN CONFERENCE ON ANTENNAS AND PROPAGATION (EUCAP)}, abstract = {This paper presents the design of a wide-band compact antenna feed for dual-band single circular polarization. The feed chain system is based on a recently proposed configuration that uses a diplexer and a bi-phase polarizer conveniently joined by a single mode waveguide. This solution leads to compact low-cost feed designs well suited for multi-beam antennas with a single feed per beam in the context of satellite communications. A new design with enhanced performance is presented with simulated results of axial ratio below 0.2 dB across 18.2-20.2 GHz and 28-30 GHz. Moreover, the impact of the finite return loss of the high efficiency horn is studied and a compensated high-performance feed is presented.}, note = {9th European Conference on Antennas and Propagation EuCAP, Lisbon, PORTUGAL, MAY 13-17, 2015}, keywords = {}, pubstate = {published}, tppubtype = {inproceedings} } This paper presents the design of a wide-band compact antenna feed for dual-band single circular polarization. The feed chain system is based on a recently proposed configuration that uses a diplexer and a bi-phase polarizer conveniently joined by a single mode waveguide. This solution leads to compact low-cost feed designs well suited for multi-beam antennas with a single feed per beam in the context of satellite communications. A new design with enhanced performance is presented with simulated results of axial ratio below 0.2 dB across 18.2-20.2 GHz and 28-30 GHz. Moreover, the impact of the finite return loss of the high efficiency horn is studied and a compensated high-performance feed is presented. |
Abdo-Sánchez, E; Camacho-Peñalosa, C; Esteban, J; Martín-Guerrero, T M Planar multiband sequentially rotated array with polarisation agility based on the complementary strip-slot element Artículo de revista Journal of Electromagnetic Waves and Applications, 29 (4), pp. 538-550, 2015. @article{AbdoSanchez2015, title = {Planar multiband sequentially rotated array with polarisation agility based on the complementary strip-slot element}, author = {E Abdo-Sánchez and C Camacho-Peñalosa and J Esteban and T M Martín-Guerrero}, doi = {10.1080/09205071.2015.1006734}, year = {2015}, date = {2015-01-01}, journal = {Journal of Electromagnetic Waves and Applications}, volume = {29}, number = {4}, pages = {538-550}, abstract = {A novel planar travelling-wave ring array with polarisation agility is introduced. The array is built by applying the sequential rotation technique with the complementary strip-slot element. This element is a conventional microstrip series-fed slot with the special feature of very broad impedance bandwidth thanks to the strip superimposed into it on the microstrip layer. The feeding of the array elements and the required phase shift between them are provided by a ring-shaped microstrip line, which is terminated in two ports. Vertical linear polarisation, horizontal linear polarisation, right-handed circular polarisation and left-handed circular polarisation can be generated with this very simple planar structure, just by controlling the phase and amplitude of the excitation at the two ports. Moreover, thanks to the wide impedance bandwidth of the element, multiband behaviour is achievable. A design example that operates at three different bands (centred around 6, 9 and 12 GHz) is analysed, which presents very good matching (|S11|< -15 dB), polarisation purity and broadside radiation pattern.}, keywords = {}, pubstate = {published}, tppubtype = {article} } A novel planar travelling-wave ring array with polarisation agility is introduced. The array is built by applying the sequential rotation technique with the complementary strip-slot element. This element is a conventional microstrip series-fed slot with the special feature of very broad impedance bandwidth thanks to the strip superimposed into it on the microstrip layer. The feeding of the array elements and the required phase shift between them are provided by a ring-shaped microstrip line, which is terminated in two ports. Vertical linear polarisation, horizontal linear polarisation, right-handed circular polarisation and left-handed circular polarisation can be generated with this very simple planar structure, just by controlling the phase and amplitude of the excitation at the two ports. Moreover, thanks to the wide impedance bandwidth of the element, multiband behaviour is achievable. A design example that operates at three different bands (centred around 6, 9 and 12 GHz) is analysed, which presents very good matching (|S11|< -15 dB), polarisation purity and broadside radiation pattern. |
Abdo-Sánchez, E; Martín-Guerrero, T M; Esteban, J; Camacho-Peñalosa, C On the Radiation Properties of the Complementary Strip-Slot Element Artículo de revista IEEE Antennas and Wireless Propagation Letters, 14 , pp. 1389-1391, 2015, ISSN: 1536-1225. @article{AbdoSanchez2015a, title = {On the Radiation Properties of the Complementary Strip-Slot Element}, author = {E Abdo-Sánchez and T M Martín-Guerrero and J Esteban and C Camacho-Peñalosa}, doi = {10.1109/LAWP.2015.2407902}, issn = {1536-1225}, year = {2015}, date = {2015-01-01}, journal = {IEEE Antennas and Wireless Propagation Letters}, volume = {14}, pages = {1389-1391}, abstract = {The complementary strip-slot radiating element is a microstrip-fed slot modified by introducing its complementary stub on the layer of the microstrip. Previous works have shown that the introduction of the stub into the conventional slot results in an ultra broad impedance bandwidth and have provided a lattice-network equivalent circuit for its precise modeling. In this contribution, an interesting property of the symmetric lattice networks is highlighted and used to illustrate why the complementary strip-slot radiates as the conventional microstrip-fed slot, thus corroborating the conclusions of previous works based on empirical results.}, keywords = {}, pubstate = {published}, tppubtype = {article} } The complementary strip-slot radiating element is a microstrip-fed slot modified by introducing its complementary stub on the layer of the microstrip. Previous works have shown that the introduction of the stub into the conventional slot results in an ultra broad impedance bandwidth and have provided a lattice-network equivalent circuit for its precise modeling. In this contribution, an interesting property of the symmetric lattice networks is highlighted and used to illustrate why the complementary strip-slot radiates as the conventional microstrip-fed slot, thus corroborating the conclusions of previous works based on empirical results. |
Esteban, J; Camacho-Peñalosa, C Compact Orthomode Transducer Polarizer Based on a Tilted-Waveguide Ŧ-Junction Artículo de revista IEEE Transactions on Microwave Theory and Techniques, 63 (10), pp. 3208-3217, 2015, ISSN: 0018-9480. @article{Esteban2015, title = {Compact Orthomode Transducer Polarizer Based on a Tilted-Waveguide Ŧ-Junction}, author = {J Esteban and C Camacho-Peñalosa}, doi = {10.1109/TMTT.2015.2461540}, issn = {0018-9480}, year = {2015}, date = {2015-01-01}, journal = {IEEE Transactions on Microwave Theory and Techniques}, volume = {63}, number = {10}, pages = {3208-3217}, abstract = {An alternative device to the well-known septum polarizer is proposed, which also provides the double function of an orthomode and a polarizer. It is based on a waveguide T-junction between a common dual-polarization waveguide and a tilted rectangular single-mode waveguide, and offers an intrinsically shorter geometry in the axial dimension, an advisable property when searching for compact antena assemblies. The analysis of this new device is presented, along with the derivation and introduction of the $S$-parameters referred to the circularly polarized modes in the common waveguide. The working principle of the proposed T-junction is also explained in detail. A breadboard is designed, and its simulation and measurement results are presented. As a conclusion, the proposed device seems worthy of comparison in its electrical performances to the septum polarizer, showing some advantages in terms of geometrical dimensions and manufacturability.}, keywords = {}, pubstate = {published}, tppubtype = {article} } An alternative device to the well-known septum polarizer is proposed, which also provides the double function of an orthomode and a polarizer. It is based on a waveguide T-junction between a common dual-polarization waveguide and a tilted rectangular single-mode waveguide, and offers an intrinsically shorter geometry in the axial dimension, an advisable property when searching for compact antena assemblies. The analysis of this new device is presented, along with the derivation and introduction of the $S$-parameters referred to the circularly polarized modes in the common waveguide. The working principle of the proposed T-junction is also explained in detail. A breadboard is designed, and its simulation and measurement results are presented. As a conclusion, the proposed device seems worthy of comparison in its electrical performances to the septum polarizer, showing some advantages in terms of geometrical dimensions and manufacturability. |
2014 |
Florencio, Rafael; Encinar, Jose A; Boix, Rafael R; Perez-Palomino, Gerardo Dual-polarisation reflectarray made of cells with two orthogonal sets of parallel dipoles for bandwidth and cross-polarisation improvement Artículo de revista IET MICROWAVES ANTENNAS & PROPAGATION, 8 (15), pp. 1389-1397, 2014, ISSN: 1751-8725. @article{Florencio2014, title = {Dual-polarisation reflectarray made of cells with two orthogonal sets of parallel dipoles for bandwidth and cross-polarisation improvement}, author = {Rafael Florencio and Jose A Encinar and Rafael R Boix and Gerardo Perez-Palomino}, doi = {10.1049/iet-map.2014.0202}, issn = {1751-8725}, year = {2014}, date = {2014-12-01}, journal = {IET MICROWAVES ANTENNAS & PROPAGATION}, volume = {8}, number = {15}, pages = {1389-1397}, abstract = {A reflectarray antenna has been proposed to provide broadband operation, low cross-polarisation and independent beamforming in dual linear polarisation. The reflectarray element consists of two orthogonal sets of three coplanar parallel dipoles, where each set of parallel dipoles is used for controlling the phase-shift of each polarisation. A focused beam 40 cm reflectarray has been designed, manufactured and tested. According to the experimental results, the antenna shows a 27% bandwidth for a gain of 32.9 dBi with a variation of 1 dB. The antenna efficiency is better than 60% and the maximum cross-polar radiation levels are at least 30 dB below the main beam co-polar levels for both linear polarisations. In addition, it has been demonstrated that the antenna performance is maintained when it is designed to provide two separate beams in each linear polarisation.}, keywords = {}, pubstate = {published}, tppubtype = {article} } A reflectarray antenna has been proposed to provide broadband operation, low cross-polarisation and independent beamforming in dual linear polarisation. The reflectarray element consists of two orthogonal sets of three coplanar parallel dipoles, where each set of parallel dipoles is used for controlling the phase-shift of each polarisation. A focused beam 40 cm reflectarray has been designed, manufactured and tested. According to the experimental results, the antenna shows a 27% bandwidth for a gain of 32.9 dBi with a variation of 1 dB. The antenna efficiency is better than 60% and the maximum cross-polar radiation levels are at least 30 dB below the main beam co-polar levels for both linear polarisations. In addition, it has been demonstrated that the antenna performance is maintained when it is designed to provide two separate beams in each linear polarisation. |
Leal-Sevillano, Carlos A; Cooper, Ken B; Decrossas, Emmanuel; Dengler, Robert J; Ruiz-Cruz, Jorge A; Montejo-Garai, Jose R; Chattopadhyay, Goutam; Rebollar, Jesus M Compact Duplexing for a 680-GHz Radar Using a Waveguide Orthomode Transducer Artículo de revista IEEE TRANSACTIONS ON MICROWAVE THEORY AND TECHNIQUES, 62 (11, SI), pp. 2833-2842, 2014, ISSN: 0018-9480. @article{LealSevillano2014, title = {Compact Duplexing for a 680-GHz Radar Using a Waveguide Orthomode Transducer}, author = {Carlos A Leal-Sevillano and Ken B Cooper and Emmanuel Decrossas and Robert J Dengler and Jorge A Ruiz-Cruz and Jose R Montejo-Garai and Goutam Chattopadhyay and Jesus M Rebollar}, doi = {10.1109/TMTT.2014.2359636}, issn = {0018-9480}, year = {2014}, date = {2014-11-01}, journal = {IEEE TRANSACTIONS ON MICROWAVE THEORY AND TECHNIQUES}, volume = {62}, number = {11, SI}, pages = {2833-2842}, abstract = {A compact 680-GHz waveguide orthomode transducer (OMT) and circular horn combination has been designed, tested, and characterized in a radar transceiver's duplexer. The duplexing capability is implemented by a hybrid waveguide quasi optical solution, combining a linear polarization OMT and an external grating polarizer. Isolation between the OMT's orthogonal ports' flanges was measured with a vector network analyzer to exceed 33 dB over a >10% bandwidth between 630 and 710 GHz. Calibrated Y-factor measurements using a mixer attached to the OMT ports reveal losses through the transmit and receive paths that sum to an average of 4.7 dB of two-way loss over 660-690 GHz. This is consistent with radar sensitivity measurements comparing the new OMT/horn with a quasi-optical wire grid beam splitter. Moreover, the radar performance assessment validates the OMT as a suitable compact substitute of the wire grid for the JPL's short-range 680-GHz imaging radar.}, keywords = {}, pubstate = {published}, tppubtype = {article} } A compact 680-GHz waveguide orthomode transducer (OMT) and circular horn combination has been designed, tested, and characterized in a radar transceiver's duplexer. The duplexing capability is implemented by a hybrid waveguide quasi optical solution, combining a linear polarization OMT and an external grating polarizer. Isolation between the OMT's orthogonal ports' flanges was measured with a vector network analyzer to exceed 33 dB over a >10% bandwidth between 630 and 710 GHz. Calibrated Y-factor measurements using a mixer attached to the OMT ports reveal losses through the transmit and receive paths that sum to an average of 4.7 dB of two-way loss over 660-690 GHz. This is consistent with radar sensitivity measurements comparing the new OMT/horn with a quasi-optical wire grid beam splitter. Moreover, the radar performance assessment validates the OMT as a suitable compact substitute of the wire grid for the JPL's short-range 680-GHz imaging radar. |
Gil, Jose M ROTATION OF CURL-CONFORMING ELEMENTS WITH DECOMPOSITION INTO LOOP-STAR SUBSPACES APPLIED TO THE SURFACE INTEGRAL EQUATION Artículo de revista MICROWAVE AND OPTICAL TECHNOLOGY LETTERS, 56 (10), pp. 2458-2462, 2014, ISSN: 0895-2477. @article{Gil2014, title = {ROTATION OF CURL-CONFORMING ELEMENTS WITH DECOMPOSITION INTO LOOP-STAR SUBSPACES APPLIED TO THE SURFACE INTEGRAL EQUATION}, author = {Jose M Gil}, doi = {10.1002/mop.28613}, issn = {0895-2477}, year = {2014}, date = {2014-10-01}, journal = {MICROWAVE AND OPTICAL TECHNOLOGY LETTERS}, volume = {56}, number = {10}, pages = {2458-2462}, keywords = {}, pubstate = {published}, tppubtype = {article} } |
Leal-Sevillano, Carlos A; Reck, Theodore J; Chattopadhyay, Goutam; Ruiz-Cruz, Jorge A; Montejo-Garai, Jose R; Rebollar, Jesus M Development of a Wideband Compact Orthomode Transducer for the 180-270 GHz Band Artículo de revista IEEE TRANSACTIONS ON TERAHERTZ SCIENCE AND TECHNOLOGY, 4 (5), pp. 634-636, 2014, ISSN: 2156-342X. @article{LealSevillano2014a, title = {Development of a Wideband Compact Orthomode Transducer for the 180-270 GHz Band}, author = {Carlos A Leal-Sevillano and Theodore J Reck and Goutam Chattopadhyay and Jorge A Ruiz-Cruz and Jose R Montejo-Garai and Jesus M Rebollar}, doi = {10.1109/TTHZ.2014.2336540}, issn = {2156-342X}, year = {2014}, date = {2014-09-01}, journal = {IEEE TRANSACTIONS ON TERAHERTZ SCIENCE AND TECHNOLOGY}, volume = {4}, number = {5}, pages = {634-636}, abstract = {In this paper, we report the development of a wideband compact orthomode transducer (OMT) for the 180-270 GHz band. The OMT design is based on the classical high performance Boifot waveguide junction and implemented in split-block using high precision CNC milling. The obtained results validate the high performance operation in a 40% fractional bandwidth and constitute a remarkable achievement at this high frequency band.}, keywords = {}, pubstate = {published}, tppubtype = {article} } In this paper, we report the development of a wideband compact orthomode transducer (OMT) for the 180-270 GHz band. The OMT design is based on the classical high performance Boifot waveguide junction and implemented in split-block using high precision CNC milling. The obtained results validate the high performance operation in a 40% fractional bandwidth and constitute a remarkable achievement at this high frequency band. |
Lopez-Berrocal, B; de-Oliva-Rubio, J; Molina-Fernandez, I; Montejo-Garai, Jose R Compact Interdigital Filters with Transmission Zeros in LTCC Technology Artículo de revista INTERNATIONAL JOURNAL OF RF AND MICROWAVE COMPUTER-AIDED ENGINEERING, 24 (5), pp. 560-570, 2014, ISSN: 1096-4290. @article{LopezBerrocal2014, title = {Compact Interdigital Filters with Transmission Zeros in LTCC Technology}, author = {B Lopez-Berrocal and J de-Oliva-Rubio and I Molina-Fernandez and Jose R Montejo-Garai}, doi = {10.1002/mmce.20799}, issn = {1096-4290}, year = {2014}, date = {2014-09-01}, journal = {INTERNATIONAL JOURNAL OF RF AND MICROWAVE COMPUTER-AIDED ENGINEERING}, volume = {24}, number = {5}, pages = {560-570}, abstract = {This article presents a simple topology for the implementation of cross-couplings between nonadjacent resonators in interdigital stripline filters. This topology affords the inclusion of transmission zeros maintaining a cross-sectional structure similar to that of a stripline. Therefore, the manufacturing cost is very close to an all-pole prototype. Two design strategies for the coupling structure are discussed: one of them achieving filters with enhanced performance. Both strategies have been assessed implementing prototypes in low-temperature cofired ceramic (LTCC) technology. The fabricated filters exhibit operating frequencies at 5775 MHz and 8000 MHz with 2.6% and 3.75% pass-band fractional bandwidths, respectively, and up to 60 dB IL in the rejection band. (c) 2014 Wiley Periodicals, Inc. Int J RF and Microwave CAE 24:560-570, 2014.}, keywords = {}, pubstate = {published}, tppubtype = {article} } This article presents a simple topology for the implementation of cross-couplings between nonadjacent resonators in interdigital stripline filters. This topology affords the inclusion of transmission zeros maintaining a cross-sectional structure similar to that of a stripline. Therefore, the manufacturing cost is very close to an all-pole prototype. Two design strategies for the coupling structure are discussed: one of them achieving filters with enhanced performance. Both strategies have been assessed implementing prototypes in low-temperature cofired ceramic (LTCC) technology. The fabricated filters exhibit operating frequencies at 5775 MHz and 8000 MHz with 2.6% and 3.75% pass-band fractional bandwidths, respectively, and up to 60 dB IL in the rejection band. (c) 2014 Wiley Periodicals, Inc. Int J RF and Microwave CAE 24:560-570, 2014. |
Perez-Palomino, Gerardo; Florencio, Rafael; Encinar, Jose A; Barba, Mariano; Dickie, Raymond; Cahill, Robert; Baine, Paul; Bain, Michael; Boix, Rafael R Accurate and Efficient Modeling to Calculate the Voltage Dependence of Liquid Crystal-Based Reflectarray Cells Artículo de revista IEEE TRANSACTIONS ON ANTENNAS AND PROPAGATION, 62 (5), pp. 2659-2668, 2014, ISSN: 0018-926X. @article{PerezPalomino2014, title = {Accurate and Efficient Modeling to Calculate the Voltage Dependence of Liquid Crystal-Based Reflectarray Cells}, author = {Gerardo Perez-Palomino and Rafael Florencio and Jose A Encinar and Mariano Barba and Raymond Dickie and Robert Cahill and Paul Baine and Michael Bain and Rafael R Boix}, doi = {10.1109/TAP.2014.2308521}, issn = {0018-926X}, year = {2014}, date = {2014-05-01}, journal = {IEEE TRANSACTIONS ON ANTENNAS AND PROPAGATION}, volume = {62}, number = {5}, pages = {2659-2668}, abstract = {Two models that can predict the voltage-dependent scattering from liquid crystal (LC)-based reflectarray cells are presented. The validity of both numerical techniques is demonstrated using measured results in the frequency range 94-110 GHz. The most rigorous approach models, for each voltage, the inhomogeneous and anisotropic permittivity of the LC as a stratified media in the direction of the biasing field. This accounts for the different tilt angles of the LC molecules inside the cell calculated from the solution of the elastic problem. The other model is based on an effective homogeneous permittivity tensor that corresponds to the average tilt angle along the longitudinal direction for each biasing voltage. In this model, convergence problems associated with the longitudinal inhomogeneity are avoided, and the computation efficiency is improved. Both models provide a correspondence between the reflection coefficient (losses and phase-shift) of the LC-based reflectarray cell and the value of biasing voltage, which can be used to design beam scanning reflectarrays. The accuracy and the efficiency of both models are also analyzed and discussed.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Two models that can predict the voltage-dependent scattering from liquid crystal (LC)-based reflectarray cells are presented. The validity of both numerical techniques is demonstrated using measured results in the frequency range 94-110 GHz. The most rigorous approach models, for each voltage, the inhomogeneous and anisotropic permittivity of the LC as a stratified media in the direction of the biasing field. This accounts for the different tilt angles of the LC molecules inside the cell calculated from the solution of the elastic problem. The other model is based on an effective homogeneous permittivity tensor that corresponds to the average tilt angle along the longitudinal direction for each biasing voltage. In this model, convergence problems associated with the longitudinal inhomogeneity are avoided, and the computation efficiency is improved. Both models provide a correspondence between the reflection coefficient (losses and phase-shift) of the LC-based reflectarray cell and the value of biasing voltage, which can be used to design beam scanning reflectarrays. The accuracy and the efficiency of both models are also analyzed and discussed. |
Doumanis, E; Goussetis, G; Dickie, Raymond; Cahill, Robert; Baine, Paul; Bain, Michael; Fusco, Vincent; Encinar, Jose A; Toso, Giovanni Electronically Reconfigurable Liquid Crystal Based Mm-Wave Polarization Converter Artículo de revista IEEE TRANSACTIONS ON ANTENNAS AND PROPAGATION, 62 (4, 2), pp. 2302-2307, 2014, ISSN: 0018-926X. @article{Doumanis2014, title = {Electronically Reconfigurable Liquid Crystal Based Mm-Wave Polarization Converter}, author = {E Doumanis and G Goussetis and Raymond Dickie and Robert Cahill and Paul Baine and Michael Bain and Vincent Fusco and Jose A Encinar and Giovanni Toso}, doi = {10.1109/TAP.2014.2302844}, issn = {0018-926X}, year = {2014}, date = {2014-04-01}, journal = {IEEE TRANSACTIONS ON ANTENNAS AND PROPAGATION}, volume = {62}, number = {4, 2}, pages = {2302-2307}, abstract = {An electronically tunable reflection polarizer which exploits the dielectric anisotropy of nematic liquid crystals (LC) has been designed, fabricated and measured in a frequency band centered at 130 GHz. The phase agile polarizing mirror converts an incident slant 45 degrees signal upon reflection to right hand circular (RHCP), orthogonal linear (-45 degrees) or left hand circular (LHCP) polarization depending on the value of the voltage biasing the LC mixture. In the experimental set-up this is achieved by applying a low frequency bias voltage of 0 V, 40 V and 89 V respectively, across the cavity containing the LC material.}, keywords = {}, pubstate = {published}, tppubtype = {article} } An electronically tunable reflection polarizer which exploits the dielectric anisotropy of nematic liquid crystals (LC) has been designed, fabricated and measured in a frequency band centered at 130 GHz. The phase agile polarizing mirror converts an incident slant 45 degrees signal upon reflection to right hand circular (RHCP), orthogonal linear (-45 degrees) or left hand circular (LHCP) polarization depending on the value of the voltage biasing the LC mixture. In the experimental set-up this is achieved by applying a low frequency bias voltage of 0 V, 40 V and 89 V respectively, across the cavity containing the LC material. |
Florencio, Rafael; Boix, Rafael R; Carrasco, Eduardo; Encinar, Jose A; Barba, Mariano; Perez-Palomino, Gerardo BROADBAND REFLECTARRAYS MADE OF CELLS WITH THREE COPLANAR PARALLEL DIPOLES Artículo de revista MICROWAVE AND OPTICAL TECHNOLOGY LETTERS, 56 (3), pp. 748-753, 2014, ISSN: 0895-2477. @article{Florencio2014a, title = {BROADBAND REFLECTARRAYS MADE OF CELLS WITH THREE COPLANAR PARALLEL DIPOLES}, author = {Rafael Florencio and Rafael R Boix and Eduardo Carrasco and Jose A Encinar and Mariano Barba and Gerardo Perez-Palomino}, doi = {10.1002/mop.28171}, issn = {0895-2477}, year = {2014}, date = {2014-03-01}, journal = {MICROWAVE AND OPTICAL TECHNOLOGY LETTERS}, volume = {56}, number = {3}, pages = {748-753}, keywords = {}, pubstate = {published}, tppubtype = {article} } |
Carrasco, Eduardo; Low, T; Perruisseau-Carrier, J Dynamic light bending with graphene plasmonic structures Artículo en actas International Conference on Metamaterials, Photonic Crystals and Plasmonics, 2014. @inproceedings{Carrasco2014, title = {Dynamic light bending with graphene plasmonic structures}, author = {Eduardo Carrasco and T Low and J Perruisseau-Carrier}, year = {2014}, date = {2014-01-01}, booktitle = {International Conference on Metamaterials, Photonic Crystals and Plasmonics}, keywords = {}, pubstate = {published}, tppubtype = {inproceedings} } |
Florencio, Rafael; Perez-Palomino, Gerardo; Encinar, Jose A; Boix, Rafael R Broadband Reflectarray Element for Dual Polarization Made of Orthogonal Sets of Parallel Dipoles Artículo en actas 8th European Conference on Antennas and Propagation, EUCAP 2014, (The Hague, The Netherlands), 2014. @inproceedings{, title = {Broadband Reflectarray Element for Dual Polarization Made of Orthogonal Sets of Parallel Dipoles}, author = {Rafael Florencio and Gerardo Perez-Palomino and Jose A Encinar and Rafael R Boix}, year = {2014}, date = {2014-01-01}, booktitle = {8th European Conference on Antennas and Propagation, EUCAP 2014, (The Hague, The Netherlands)}, keywords = {}, pubstate = {published}, tppubtype = {inproceedings} } |
Florencio, Rafael; Boix, Rafael R; Carrasco, Eduardo; Encinar, Jose A; Barba, Mariano; Pérez-Palomino, Gerardo Broadband reflectarrays made of cells with three coplanar parallel dipoles Artículo de revista 2014. @article{, title = {Broadband reflectarrays made of cells with three coplanar parallel dipoles}, author = {Rafael Florencio and Rafael R Boix and Eduardo Carrasco and Jose A Encinar and Mariano Barba and Gerardo Pérez-Palomino}, doi = {10.1002/mop.28171}, year = {2014}, date = {2014-01-01}, abstract = {A broadband reflectarray cell made of three parallel dipoles printed on a dielectric layer is presented. A 33% bandwidth is achieved for the cell made of dipoles, which is larger than that obtained for a reference cell consisting of three stacked square patches (26%). Using this cell, a 41‐cm reflectarray antenna has been designed to produce a collimated beam at 9.5 GHz. The numerical results obtained for the reflectarray antenna made of parallel dipoles show a 1‐dB bandwidth of 19%, a 65% efficiency, 0.2 dB of losses, and low levels of cross polarization (25 dB below the maximum). These results demonstrate a high performance for the proposed reflectarray antenna made of cells with three printed dipoles.}, keywords = {}, pubstate = {published}, tppubtype = {article} } A broadband reflectarray cell made of three parallel dipoles printed on a dielectric layer is presented. A 33% bandwidth is achieved for the cell made of dipoles, which is larger than that obtained for a reference cell consisting of three stacked square patches (26%). Using this cell, a 41‐cm reflectarray antenna has been designed to produce a collimated beam at 9.5 GHz. The numerical results obtained for the reflectarray antenna made of parallel dipoles show a 1‐dB bandwidth of 19%, a 65% efficiency, 0.2 dB of losses, and low levels of cross polarization (25 dB below the maximum). These results demonstrate a high performance for the proposed reflectarray antenna made of cells with three printed dipoles. |
Corcoles, Juan; Gonzalez-de-Aza, Miguel A; Zapata, Juan Full-wave analysis of finite periodic cylindrical conformal arrays with Floquet spherical modes and a hybrid finite element - generalized scattering matrix method Artículo de revista JOURNAL OF ELECTROMAGNETIC WAVES AND APPLICATIONS, 28 (1), pp. 102-111, 2014, ISSN: 0920-5071. @article{Corcoles2014, title = {Full-wave analysis of finite periodic cylindrical conformal arrays with Floquet spherical modes and a hybrid finite element - generalized scattering matrix method}, author = {Juan Corcoles and Miguel A Gonzalez-de-Aza and Juan Zapata}, doi = {10.1080/09205071.2013.857280}, issn = {0920-5071}, year = {2014}, date = {2014-01-01}, journal = {JOURNAL OF ELECTROMAGNETIC WAVES AND APPLICATIONS}, volume = {28}, number = {1}, 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'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 = {}, pubstate = {published}, tppubtype = {article} } 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'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. |
Echeveste, Jose Ignacio; Gonzalez-de-Aza, Miguel A; Zapata, Juan AEP and Mutual Coupling Formulation for Antenna Array Synthesis via Convex Optimization Artículo en actas 2014 IEEE ANTENNAS AND PROPAGATION SOCIETY INTERNATIONAL SYMPOSIUM (APSURSI), pp. 1732-1733, Inst Elect Elect Engineers; Inst Elect Elect Engineers Antennas & Propagat Soc 2014, ISSN: 1522-3965, (IEEE Antennas-and-Propagation-Society International Symposium (APSURSI), Memphis, TN, JUL 06-11, 2014). @inproceedings{EchevesteGuzman2014, title = {AEP and Mutual Coupling Formulation for Antenna Array Synthesis via Convex Optimization}, author = {Jose Ignacio Echeveste and Miguel A Gonzalez-de-Aza and Juan Zapata}, issn = {1522-3965}, year = {2014}, date = {2014-01-01}, booktitle = {2014 IEEE ANTENNAS AND PROPAGATION SOCIETY INTERNATIONAL SYMPOSIUM (APSURSI)}, pages = {1732-1733}, organization = {Inst Elect Elect Engineers; Inst Elect Elect Engineers Antennas & Propagat Soc}, series = {IEEE Antennas and Propagation Society International Symposium}, abstract = {This work proposes the integration of an electromagnetic analysis of a finite array through infinite array results and an array beampattern synthesis methodology from linear programming. The periodic radiating elements are characterized from a full wave and modular procedure based on domain decomposition, 3D-FEM, modal analysis and matrix formulation. The technique takes into account real radiating patterns of antennas with complex geometry and the mutual coupling between the array elements.}, note = {IEEE Antennas-and-Propagation-Society International Symposium (APSURSI), Memphis, TN, JUL 06-11, 2014}, keywords = {}, pubstate = {published}, tppubtype = {inproceedings} } This work proposes the integration of an electromagnetic analysis of a finite array through infinite array results and an array beampattern synthesis methodology from linear programming. The periodic radiating elements are characterized from a full wave and modular procedure based on domain decomposition, 3D-FEM, modal analysis and matrix formulation. The technique takes into account real radiating patterns of antennas with complex geometry and the mutual coupling between the array elements. |
2016 |
Comprehensive Validation and Uncertainty Evaluation of New SAR Measurement Technologies Artículo en actas 2016 10TH EUROPEAN CONFERENCE ON ANTENNAS AND PROPAGATION (EUCAP), 2016, ISSN: 2164-3342, (10th European Conference on Antennas and Propagation (EuCAP), Davos, SWITZERLAND, APR 10-15, 2016). |
Mid-Infrared Reflectarrays Based on an Aperiodic Graphene Nanostrips Array Artículo en actas 10th European Conference on Antennas and Propagation (EuCAP 2016), 2016. |
Single-Layer Dual-Frequency Reflectarray for Ka-Band Antennas Artículo en actas 2016 10TH EUROPEAN CONFERENCE ON ANTENNAS AND PROPAGATION (EUCAP), 2016, ISSN: 2164-3342, (10th European Conference on Antennas and Propagation (EuCAP), Davos, SWITZERLAND, APR 10-15, 2016). |
Tri-Band FSS for Ku/Ka Bands Reflector Antennas Artículo en actas 2016 10TH EUROPEAN CONFERENCE ON ANTENNAS AND PROPAGATION (EUCAP), 2016, ISSN: 2164-3342, (10th European Conference on Antennas and Propagation (EuCAP), Davos, SWITZERLAND, APR 10-15, 2016). |
Cross-polar Reduction in Reflectarray Antennas by means of Element Rotation Artículo en actas 2016 10TH EUROPEAN CONFERENCE ON ANTENNAS AND PROPAGATION (EUCAP), 2016, ISSN: 2164-3342, (10th European Conference on Antennas and Propagation (EuCAP), Davos, SWITZERLAND, APR 10-15, 2016). |
A Confocal Reflector for a Reflectarray-based Scanning System Artículo en actas 2016 10TH EUROPEAN CONFERENCE ON ANTENNAS AND PROPAGATION (EUCAP), 2016, ISSN: 2164-3342, (10th European Conference on Antennas and Propagation (EuCAP), Davos, SWITZERLAND, APR 10-15, 2016). |
Dual Polarized Reflectarray Antenna to Generate Independent Beams in Ku and Ka Bands Artículo en actas 2016 10TH EUROPEAN CONFERENCE ON ANTENNAS AND PROPAGATION (EUCAP), 2016, ISSN: 2164-3342, (10th European Conference on Antennas and Propagation (EuCAP), Davos, SWITZERLAND, APR 10-15, 2016). |
Reflectarray Antenna with Reduced Crosspolar Radiation Pattern Artículo en actas 2016 10TH EUROPEAN CONFERENCE ON ANTENNAS AND PROPAGATION (EUCAP), 2016, ISSN: 2164-3342, (10th European Conference on Antennas and Propagation (EuCAP), Davos, SWITZERLAND, APR 10-15, 2016). |
Reflectarray in K and Ka Bands with Independent Beams in Each Polarization Artículo en actas 2016 IEEE ANTENNAS AND PROPAGATION SOCIETY INTERNATIONAL SYMPOSIUM, pp. 1199-1200, Inst Elect & Elect Engineers Antennas & Propagat Soc; Inst Elect & Elect Engineers 2016, ISSN: 1522-3965, (IEEE-Antennas-and-Propagation-Society International Symposium, Fajardo, PR, JUN 26-JUL 01, 2016). |
Multibeam Reflectarray for Transmit Satellite Antennas in Ka Band Using Beam-Squint Artículo en actas 2016 IEEE ANTENNAS AND PROPAGATION SOCIETY INTERNATIONAL SYMPOSIUM, pp. 1421-1422, Inst Elect & Elect Engineers Antennas & Propagat Soc; Inst Elect & Elect Engineers 2016, ISSN: 1522-3965, (IEEE-Antennas-and-Propagation-Society International Symposium, Fajardo, PR, JUN 26-JUL 01, 2016). |
Design, Manufacture, and Measurement of a Low-Cost Reflectarray for Global Earth Coverage Artículo de revista IEEE ANTENNAS AND WIRELESS PROPAGATION LETTERS, 15 , pp. 1418-1421, 2016, ISSN: 1536-1225. |
On the higher-order approximations for computational electromagnetics Artículo en actas Oviedo, Spain, 2016. |
Shaped beam synthesis of sparse arrays of coupled elements through a modified Orthogonal Matching Pursuit algorithm and multiple dictionaries Artículo en actas pp. 1–3, IEEE, Davos, 2016, ISBN: 978-8-8907-0186-3. |
Loop-star decomposition for any order basis functions with processing of weak and nearly singularities for the surface integral equation Artículo en actas pp. 1–3, IEEE, Davos, 2016, ISBN: 978-8-8907-0186-3. |
Broadband and High-Purity Ku-Band Circular TE01-Mode Converter Artículo en actas 2016 ASIA-PACIFIC MICROWAVE CONFERENCE (APMC2016), IEEE; MTTS; IEEE Delhi Sect; European Microwave Assoc 2016, ISBN: 978-1-5090-1592-4, (Asia-Pacific Microwave Conference (APMC), New Delhi, INDIA, DEC 05-09, 2016). |
Generalized Scattering Matrix of the Discontinuity between an Equilateral Triangular Waveguide and a Rectangular, Circular or Elliptical Waveguide Artículo en actas 2016 ASIA-PACIFIC MICROWAVE CONFERENCE (APMC2016), IEEE; MTTS; IEEE Delhi Sect; European Microwave Assoc 2016, ISBN: 978-1-5090-1592-4, (Asia-Pacific Microwave Conference (APMC), New Delhi, INDIA, DEC 05-09, 2016). |
A Virtual Lossy Dielectric Model with Composite Boundary Conditions for the Analysis of Substrate Integrated Waveguides Artículo en actas 2016 46TH EUROPEAN MICROWAVE CONFERENCE (EUMC), pp. 162-165, APS 2016, ISSN: 2325-0305, (46th European Microwave Conference (EuMC), London, ENGLAND, OCT 04-06, 2016). |
Analysis of Waveguide Discontinuities with Lateral and Transverse Perfect Magnetic Wall Boundary Conditions Artículo en actas 2016 URSI INTERNATIONAL SYMPOSIUM ON ELECTROMAGNETIC THEORY (EMTS), pp. 811-814, URSI, Commiss B 2016, ISSN: 2163-405X, (URSI-Commission-B International Symposium on Electromagnetic Theory (EMTS), Espoo, FINLAND, AUG 14-18, 2016). |
Electromagnetic Scattering at the Waveguide Step between Equilateral Triangular Waveguides Artículo de revista ADVANCES IN MATHEMATICAL PHYSICS, 2016 , 2016, ISSN: 1687-9120. |
Short dual-band planar leaky-wave antenna with broadside effect mitigation Artículo de revista IET Microwaves, Antennas and Propagation, 10 (5), pp. 574-578, 2016, ISSN: 1751-8725. |
2015 |
Array Pattern Synthesis of Real Antennas Using the Infinite-Array Approach and Linear Programming Artículo de revista IEEE TRANSACTIONS ON ANTENNAS AND PROPAGATION, 63 (12), pp. 5417-5424, 2015, ISSN: 0018-926X. |
Design and Demonstration of an Electronically Scanned Reflectarray Antenna at 100 GHz Using Multiresonant Cells Based on Liquid Crystals Artículo de revista IEEE TRANSACTIONS ON ANTENNAS AND PROPAGATION, 63 (8), pp. 3722-3727, 2015, ISSN: 0018-926X. |
A self-diplexing dual-band planar array for GNSS applications Artículo en actas 2015 IEEE International Symposium on Antennas and Propagation USNC/URSI National Radio Science Meeting, pp. 1874-1875, Vancouver (Canada), 2015, ISSN: 1522-3965, (ISSN: 1522-3965). |
Fast and Accurate MoM Analysis of Periodic Arrays of Multilayered Stacked Rectangular Patches With Application to the Design of Reflectarray Antennas Artículo de revista IEEE TRANSACTIONS ON ANTENNAS AND PROPAGATION, 63 (6), pp. 2558-2571, 2015, ISSN: 0018-926X. |
On the phase response and radiation efficiency of the complementary strip-slot as an array element Artículo en actas 2015 9th European Conference on Antennas and Propagation (EuCAP), pp. 1-4, Lisbon (Portugal), 2015, ISSN: 2164-3342, (ISSN: 2164-3342). |
Reflectarray Antennas for Dual Polarization and Broadband Telecom Satellite Applications Artículo de revista IEEE TRANSACTIONS ON ANTENNAS AND PROPAGATION, 63 (4, 1, SI), pp. 1234-1246, 2015, ISSN: 0018-926X. |
A Transportable Reflectarray Antenna for Satellite Ku-band Emergency Communications Artículo de revista IEEE TRANSACTIONS ON ANTENNAS AND PROPAGATION, 63 (4, 1, SI), pp. 1393-1407, 2015, ISSN: 0018-926X. |
Design of Broadband Transmitarray Unit Cells With Comparative Study of Different Numbers of Layers Artículo de revista IEEE TRANSACTIONS ON ANTENNAS AND PROPAGATION, 63 (4, 1, SI), pp. 1473-1481, 2015, ISSN: 0018-926X. |
Gate-controlled mid-infrared light bending with aperiodic graphene nanoribbons array Artículo de revista NANOTECHNOLOGY, 26 (13), 2015, ISSN: 0957-4484. |
Rotation of curl-conforming elements for a frequency stable application to the Surface Integral Equation Artículo en actas 2015 USNC-URSI RADIO SCIENCE MEETING (JOINT WITH AP-S SYMPOSIUM) PROCEEDINGS, pp. 125, Inst Elect Elect Engineers; IEEE Antennas Propagat Soc; IEEE; URSI 2015, ISSN: 2572-3804, (USNC-URSI Radio Science Meeting (Joint with AP-S Symposium) Proceedings, Vancouver, CANADA, JUL 19-19, 2015). |
Enhanced Integral Equation Analysis of Multilayered Periodic Structures Useful for the Design of Reflectarray Antennas Artículo en actas PROCEEDINGS OF THE 2015 INTERNATIONAL CONFERENCE ON ELECTROMAGNETICS IN ADVANCED APPLICATIONS (ICEAA), pp. 86-89, Politecnico Torino; IEIIT CNR; Int Union Radio Sci; IEEE Antennas & Propagat Soc; IEEE Italy Sect; IEEE N Italy AP ED MTT Chapter; Ist Superiore Mario Boella, Tecnologie Informazione Telecomunicazione; Torino Wireless Fdn; IEEE Antenna & Propagat Soc 2015, ISBN: 978-1-4799-7806-9, (International Conference on Electromagnetics in Advanced Applications / IEEE-APS Topical Conference on Antennas and Propagation in Wireless Communications, Torino, ITALY, SEP 07-11, 2015). |
Development of Folded Dual-Polarization Dividers for Broadband Ortho-Mode Transducers Artículo en actas {Hong, W; Zhu, X; Yang, G; Song, Z; Meng, F} (Ed.): 2015 ASIA-PACIFIC MICROWAVE CONFERENCE (APMC), VOLS 1-3, SE Univ; Nanjing Univ Sci & Technol; Chinese Inst Elect; IEEE Microwave Theory & Tech Soc; European Microwave Assoc; IEEE Antennas & Propagat Soc; Sci & Technol Antenna & Microwave Lab; State Key Lab Millimeter Waves; Jiangsu Inst Elect; IEEE AP MTT EMC Joint Nanjing Chapter; Journal Microwaves 2015, ISBN: 978-1-4799-8767-2, (Asia-Pacific Microwave Conference (APMC), Nanjing, PEOPLES R CHINA, DEC 06-09, 2015). |
Design of Microwave Waveguide Devices for Space and Ground Application Implemented by Additive Manufacturing Artículo en actas PROCEEDINGS OF THE 2015 INTERNATIONAL CONFERENCE ON ELECTROMAGNETICS IN ADVANCED APPLICATIONS (ICEAA), pp. 325-328, Politecnico Torino; IEIIT CNR; Int Union Radio Sci; IEEE Antennas & Propagat Soc; IEEE Italy Sect; IEEE N Italy AP ED MTT Chapter; Ist Superiore Mario Boella, Tecnologie Informazione Telecomunicazione; Torino Wireless Fdn; IEEE Antenna & Propagat Soc 2015, ISBN: 978-1-4799-7806-9, (International Conference on Electromagnetics in Advanced Applications / IEEE-APS Topical Conference on Antennas and Propagation in Wireless Communications, Torino, ITALY, SEP 07-11, 2015). |
Wide-Band Compact Antenna Feed for Multi-Beam Satellite Communications Artículo en actas 2015 9TH EUROPEAN CONFERENCE ON ANTENNAS AND PROPAGATION (EUCAP), 2015, ISBN: 978-8-8907-0185-6, (9th European Conference on Antennas and Propagation EuCAP, Lisbon, PORTUGAL, MAY 13-17, 2015). |
Planar multiband sequentially rotated array with polarisation agility based on the complementary strip-slot element Artículo de revista Journal of Electromagnetic Waves and Applications, 29 (4), pp. 538-550, 2015. |
On the Radiation Properties of the Complementary Strip-Slot Element Artículo de revista IEEE Antennas and Wireless Propagation Letters, 14 , pp. 1389-1391, 2015, ISSN: 1536-1225. |
Compact Orthomode Transducer Polarizer Based on a Tilted-Waveguide Ŧ-Junction Artículo de revista IEEE Transactions on Microwave Theory and Techniques, 63 (10), pp. 3208-3217, 2015, ISSN: 0018-9480. |
2014 |
Dual-polarisation reflectarray made of cells with two orthogonal sets of parallel dipoles for bandwidth and cross-polarisation improvement Artículo de revista IET MICROWAVES ANTENNAS & PROPAGATION, 8 (15), pp. 1389-1397, 2014, ISSN: 1751-8725. |
Compact Duplexing for a 680-GHz Radar Using a Waveguide Orthomode Transducer Artículo de revista IEEE TRANSACTIONS ON MICROWAVE THEORY AND TECHNIQUES, 62 (11, SI), pp. 2833-2842, 2014, ISSN: 0018-9480. |
ROTATION OF CURL-CONFORMING ELEMENTS WITH DECOMPOSITION INTO LOOP-STAR SUBSPACES APPLIED TO THE SURFACE INTEGRAL EQUATION Artículo de revista MICROWAVE AND OPTICAL TECHNOLOGY LETTERS, 56 (10), pp. 2458-2462, 2014, ISSN: 0895-2477. |
Development of a Wideband Compact Orthomode Transducer for the 180-270 GHz Band Artículo de revista IEEE TRANSACTIONS ON TERAHERTZ SCIENCE AND TECHNOLOGY, 4 (5), pp. 634-636, 2014, ISSN: 2156-342X. |
Compact Interdigital Filters with Transmission Zeros in LTCC Technology Artículo de revista INTERNATIONAL JOURNAL OF RF AND MICROWAVE COMPUTER-AIDED ENGINEERING, 24 (5), pp. 560-570, 2014, ISSN: 1096-4290. |
Accurate and Efficient Modeling to Calculate the Voltage Dependence of Liquid Crystal-Based Reflectarray Cells Artículo de revista IEEE TRANSACTIONS ON ANTENNAS AND PROPAGATION, 62 (5), pp. 2659-2668, 2014, ISSN: 0018-926X. |
Electronically Reconfigurable Liquid Crystal Based Mm-Wave Polarization Converter Artículo de revista IEEE TRANSACTIONS ON ANTENNAS AND PROPAGATION, 62 (4, 2), pp. 2302-2307, 2014, ISSN: 0018-926X. |
BROADBAND REFLECTARRAYS MADE OF CELLS WITH THREE COPLANAR PARALLEL DIPOLES Artículo de revista MICROWAVE AND OPTICAL TECHNOLOGY LETTERS, 56 (3), pp. 748-753, 2014, ISSN: 0895-2477. |
Dynamic light bending with graphene plasmonic structures Artículo en actas International Conference on Metamaterials, Photonic Crystals and Plasmonics, 2014. |
Broadband Reflectarray Element for Dual Polarization Made of Orthogonal Sets of Parallel Dipoles Artículo en actas 8th European Conference on Antennas and Propagation, EUCAP 2014, (The Hague, The Netherlands), 2014. |
Broadband reflectarrays made of cells with three coplanar parallel dipoles Artículo de revista 2014. |
Full-wave analysis of finite periodic cylindrical conformal arrays with Floquet spherical modes and a hybrid finite element - generalized scattering matrix method Artículo de revista JOURNAL OF ELECTROMAGNETIC WAVES AND APPLICATIONS, 28 (1), pp. 102-111, 2014, ISSN: 0920-5071. |
AEP and Mutual Coupling Formulation for Antenna Array Synthesis via Convex Optimization Artículo en actas 2014 IEEE ANTENNAS AND PROPAGATION SOCIETY INTERNATIONAL SYMPOSIUM (APSURSI), pp. 1732-1733, Inst Elect Elect Engineers; Inst Elect Elect Engineers Antennas & Propagat Soc 2014, ISSN: 1522-3965, (IEEE Antennas-and-Propagation-Society International Symposium (APSURSI), Memphis, TN, JUL 06-11, 2014). |
