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- His research interest include horn antenna design in general, satellite and terrestrial communications, study of peri... moreHis research interest include horn antenna design in general, satellite and terrestrial communications, study of periodic structures, Coherently Radiating Periodic Structures (CORPS), cooperative beam forming networks, meta-materials applied to antenna applications, hyperacuity, inverse problem copying the human eye, image processing, development of numerical computation software based on mode matching and scattering matrix, antenna measurements, far-and near field measurement chambers, compact ranges, etc.edit
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A novel photonic-assisted 2-D Terahertz beam steering chip using only two tuning elements is presented. The chip is based on an array of three leaky wave antennas (LWAs) with a monolithically integrated beamforming network (BFN) on a... more
A novel photonic-assisted 2-D Terahertz beam steering chip using only two tuning elements is presented. The chip is based on an array of three leaky wave antennas (LWAs) with a monolithically integrated beamforming network (BFN) on a 50 µm-thick indium phosphide substrate. The THz beam angle in elevation (E-plane) is controlled via optical frequency tuning using a tunable dual-wavelength laser. An optical delay line is used for azimuth (H-plane) beam control. The simulated beam scanning range is 92° in elevation for a frequency sweep from 0.23 THz to 0.33 THz and 69.18° in azimuth for a time delay of 3.6 ps. For the frequency range from 0.26 THz to 0.32 THz, it is confirmed experimentally that the THz beam scans from −12° to +33°, which is in good agreement with the numerical simulations. The beam direction in azimuth scans with a total angle of 39° when applying a delay difference of 1.68 ps. A good agreement is found between theoretically predicted and experimentally determined TH...
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This paper presents a new research in the field of timed antenna arrays. The study proposes the synthesis of timed antenna array for arbitrary shaped beam energy patterns. The synthesis is formulated as an optimization of the true-time... more
This paper presents a new research in the field of timed antenna arrays. The study proposes the synthesis of timed antenna array for arbitrary shaped beam energy patterns. The synthesis is formulated as an optimization of the true-time delays and amplitude coefficients in order to obtain a desired mask and low side lobes. The optimization is by using the well-known particle swarm optimization. The simulation results show the performance of timed antenna arrays to provide accurate arbitrary shaped beam energy patterns.
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In this work we present a computer based calculation that permits to understand the effect of the spurious TE03 mode into the design procedu- re of TE02-TE01 mode converters in highly overmoded circular smooth waveguides,for severals... more
In this work we present a computer based calculation that permits to understand the effect of the spurious TE03 mode into the design procedu- re of TE02-TE01 mode converters in highly overmoded circular smooth waveguides,for severals frequencies and diameters.
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This document reports a design of a microstrip patch antenna array for a uniform power density in a wide spatial range. The antenna array regards disk patch antennas modeled by the cavity model as well as coupling effects at 1.6 GHz. The... more
This document reports a design of a microstrip patch antenna array for a uniform power density in a wide spatial range. The antenna array regards disk patch antennas modeled by the cavity model as well as coupling effects at 1.6 GHz. The obtained results can reduce considerably the volume occupation and hardware complexity of the antenna array mounted on a LEO satellite. The well-known particle swarm optimization is performed to obtain the optimal values of voltage excitations.
The design of an aperiodic array is presented in this research. This design of aperiodic array considers the reduction of the side lobe level and the isoflux radiation requirements for GEO (Geostationary Earth orbit) satellite... more
The design of an aperiodic array is presented in this research. This design of aperiodic array considers the reduction of the side lobe level and the isoflux radiation requirements for GEO (Geostationary Earth orbit) satellite applications. In this way, it is considered an optimization of positions of the antenna elements and levels of amplitude excitation. For the optimization problem, the
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Telecommunication satellite horn antennas require now-a-days more and more stringent requirements based mainly in the increased bandwidth necessary to accommodate more transponders to increase the capacity of the new satellite services.... more
Telecommunication satellite horn antennas require now-a-days more and more stringent requirements based mainly in the increased bandwidth necessary to accommodate more transponders to increase the capacity of the new satellite services. In this aspect horn antennas play a key role in the development of wider bandwidth services on board satellites because they are usually the reason that limits bandwidth in
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Page 1. A Multi-beam Planar Antenna Array using CORPS and Evolutionary Optimization Leopoldo A. Garza Alvarado Universidad Autónoma de Tamaulipas, UAMRR Reynosa, Tamaulipas, México leopoldo.garza@yahoo.com ... Addison-Wesley,... more
Page 1. A Multi-beam Planar Antenna Array using CORPS and Evolutionary Optimization Leopoldo A. Garza Alvarado Universidad Autónoma de Tamaulipas, UAMRR Reynosa, Tamaulipas, México leopoldo.garza@yahoo.com ... Addison-Wesley, Massachusetts, 1989. ...
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ABSTRACT This paper presents a synthesis of a volumetric ring array for satellite applications. This synthesis regards the spacing among the rings on the planes X-Y and the positions of the rings on the plane X-Z. The well-known method of... more
ABSTRACT This paper presents a synthesis of a volumetric ring array for satellite applications. This synthesis regards the spacing among the rings on the planes X-Y and the positions of the rings on the plane X-Z. The well-known method of the particle swarm optimization is utilized for this optimization problem. The obtained results shows the proper performance of this new geometry to provide a uniform global coverage to be applied in satellite applications with a maximum reduction of the antenna hardware as well as the side lobe level reduction. This design reduced the antenna hardware even more that the results presented previously in the literature.
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This paper presents a synthesis of a volumetric ring antenna array for a terrestrial coverage pattern. This synthesis regards the spacing among the rings on the planesX-Y, the positions of the rings on the planeX-Z, and uniform and... more
This paper presents a synthesis of a volumetric ring antenna array for a terrestrial coverage pattern. This synthesis regards the spacing among the rings on the planesX-Y, the positions of the rings on the planeX-Z, and uniform and concentric excitations. The optimization is carried out by implementing the particle swarm optimization. The synthesis is compared with previous designs by resulting with proper performance of this geometry to provide an accurate coverage to be applied in satellite applications with a maximum reduction of the antenna hardware as well as the side lobe level reduction.
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ABSTRACT This research presents a design of a microstrip patch antenna array for a reconfigurable wide coverage pattern. The antenna array regards disk patch antennas modeled by the cavity model as well as coupling effects at 2.8 GHz. The... more
ABSTRACT This research presents a design of a microstrip patch antenna array for a reconfigurable wide coverage pattern. The antenna array regards disk patch antennas modeled by the cavity model as well as coupling effects at 2.8 GHz. The results can reduce considerably hardware complexity of the antenna array mounted in a satellite at different altitudes. The wellknown particle swarm optimization is performed to obtain the optimal values of voltage excitations.
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This report presents a novel design of concentric ring antenna array for a reconfigurable isoflux pattern. The array considers 61 disk patch antennas including mutual coupling by using the cavity model at the frequency of 2.8 GHz. The... more
This report presents a novel design of concentric ring antenna array for a reconfigurable isoflux pattern. The array considers 61 disk patch antennas including mutual coupling by using the cavity model at the frequency of 2.8 GHz. The problem consists in finding out a few levels of excitations for the disk patch antennas. Harmony search algorithm and particle swarm optimization are implemented for this optimization problem. This novel design permits to reduce the complexity of the antenna hardware in the whole antenna system mounted in a satellite, where the volume occupation and heat dissipations are critical issues.
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Page 1. Superb Gaussian Beam Efficiency Corrugated Horn Antennas Jorge Teniente, Ramón Gonzalo, Carlos del Río Antenna Group. TSC Area. IEE Department. ... Antenna noise originates from the sky background, ohmic losses, and ground pickup... more
Page 1. Superb Gaussian Beam Efficiency Corrugated Horn Antennas Jorge Teniente, Ramón Gonzalo, Carlos del Río Antenna Group. TSC Area. IEE Department. ... Antenna noise originates from the sky background, ohmic losses, and ground pickup or spillover from sidelobes. ...
Research Interests: Physics, Optics, Radio Astronomy, Antennas & Radio Wave Propagation, French horn, and 13 moreNoise reduction, Directional Antenna, Polarisation, High performance, Gaussian, Background Noise, Radio Telescope, Radiometers, Horn Antenna, Beamwidth, Radiation Pattern, Antenna measurements, and Return Loss
This paper deals with the design of beam-forming networks (BFN) for scannable multibeam antenna arrays using coherently radiating periodic structures (CORPS). This design of CORPS-BFN considers the optimization of the complex inputs of... more
This paper deals with the design of beam-forming networks (BFN) for scannable multibeam antenna arrays using coherently radiating periodic structures (CORPS). This design of CORPS-BFN considers the optimization of the complex inputs of the feeding network by using the differential evolution (DE) algorithm. Simulation results for different configurations of CORPS-BFN for a scannable multibeam linear array are presented. The results
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ABSTRACT This paper deals with the design of beam-forming networks (BFNs) using coherently radiating periodic structures (CORPS) and evolutionary optimization. This design of feeding networks using the principles of CORPS considers the... more
ABSTRACT This paper deals with the design of beam-forming networks (BFNs) using coherently radiating periodic structures (CORPS) and evolutionary optimization. This design of feeding networks using the principles of CORPS considers the optimization of the complex inputs of the network by using genetic algorithms. Some results obtained by simulation for a CORPS network of several layers are presented. The results shown in this paper present certain improvement in the array factor response and the network simplification for the design of CORPS network over a conventional BFNs.
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Research Interests: Mathematics and Physics
Trabajo presentado a la 21st International Conference on Infrared and Millimeter Waves. Berlin, 1996.
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Trabajo presentado al XI Simposium de la Union Cientifica Internacional de Radio (URSI'96). Madrid, 1996.
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Trabajo presentado a la European Conference on Antennas and Propagation (EuCAP 2010). Barcelona, 2010.
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Trabajo presentado al 27th ESA Antenna Technology Workshop on Innovative Periodic Antenna. Santiago de Compostela, 2004.
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Trabajo presentado a la European Conference on Antennas and Propagation (EuCAP 2010). Barcelona, 2010.
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Trabajo presentado al XIX Simposium de la Union Cientifica Internacional de Radio (URSI'04). Barcelona, 2004.
Research Interests: Art and Radiation Pattern
Trabajo presentado al 27th ESA Antenna Technology Workshop on Innovative Periodic Antenna. Santiago de Compostela, 2004.
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In this paper a new philosophy to design antenna systems is presented. It is based on the recently proposed Coherently Radiating Periodic Structures (CORPS). These structures are essentially a periodic structure which all the elements are... more
In this paper a new philosophy to design antenna systems is presented. It is based on the recently proposed Coherently Radiating Periodic Structures (CORPS). These structures are essentially a periodic structure which all the elements are radiating elements coupled coherently (in-phase). This principle could allow the designer to simplify the needed feeding network for many array antenna systems since some elements could be coupled from the neighbouring ones, keeping the original excitation profile. It will be also shown in this paper how the three dimensional version of CORPS could be understood as a focusing planar lens, since it is possible to distribute the information of one element to many radiating elements by using the coherent coupling mechanism between all the elements of the whole structure. With this configuration, many directive beams could be really close to each other, increasing the possibilities to handle high resolution in imaging systems.
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Trabajo presentado al XI Simposium de la Union Cientifica Internacional de Radio (URSI'96). Madrid, septiembre de 1996.
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Trabajo presentado al XIX Simposium de la Union Cientifica Internacional de Radio (URSI'04). Barcelona, 2004.
The ASTRA 3B satellite includes 60 Ku-band state-of the-art transponders and 4 Ka-band transponders. Th e spacecraft have been designed for the distribution of both direct-to-home (DTH) broadcast services and tw oway broadband services... more
The ASTRA 3B satellite includes 60 Ku-band state-of the-art transponders and 4 Ka-band transponders. Th e spacecraft have been designed for the distribution of both direct-to-home (DTH) broadcast services and tw oway broadband services across Europe. After Astra 2 B and Astra 1M, Astra 3B is the third Astra satellite to be built by ASTRIUM. Two different horn antennas, for Kuand Ka-bands, were designed with very stringent requirements as i t i usually required for space applications. For the ho rns the cross-polar levels should be below -45 dB, and the return loss below -30dB for all frequency bands. Normally the horn aperture is fixed by the required illumination of the reflector edges, so it is diffi cult to reduce the aperture size of a horn antenna. Neverth el ss, thanks to the design technique used, the relation between the output aperture and the total horn leng th for the Ka-band was approximately 0.56 and for the Kuband was something like 0.76. This means that the lengths of...
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ABSTRACT Since Professor Veselago in the Sixties glimpsed the characteristics of Meta-materials (also called: Left Handed materials- LH, Double Negative Materials- DNG, Composite Right/Left-Handed Structures - CRLH, among others) few... more
ABSTRACT Since Professor Veselago in the Sixties glimpsed the characteristics of Meta-materials (also called: Left Handed materials- LH, Double Negative Materials- DNG, Composite Right/Left-Handed Structures - CRLH, among others) few structures with left handed properties exist, that is to say, with negative and . These structures, e.g., Split Rings and Mushrooms widely have been studied in the last decade. In this paper, the study of the new Coherently Radiating Periodic Structures (CORPS) like a Meta-material sets out. The shape of the structure under study is composed by two different layers, one layer is an array of square metallic patches and the other layer is an array of cross shaped slots. All the elements of each layer are placed in a rectangular lattice grid of g, ensuring coherent coupling between elements of the same layer being this the main feature of the Coherently Radiating Periodic Structures (CORPS). To built up the whole structure, a total number of three layers (patches-slots-patches) are stacked and separated by dielectric slabs of either 10.2 or 1.0006 (air) of permittivity. The simulations were done using MoM and Finite Elements Method (i.e. Ansoft Designer and HFSS respectively). The study of the structure begins analyzing the characteristics of each layer separately, obtaining the transmission parameters for the cross-shape Slots Array and two layer of Array of Patches. Also, in each one to identify the real part of and using the approach of Nicolson–Ross–Weir (NRW) [1] to find out the effective parameters of the structure for normal incidence. The same procedure is applied to the stacked structure made up of Patches Array with the cross-shape Slot Array in middle to form the complete Patch-Slot-Patch structure. As result is verified the existence of negative and parameters, as well as the existence of negative refractive index for a range of frequencies where additionally was found high transmission. Similarly, it is verify that the structure is electrically small (i.e. Kreal*d≤1, where K refers to the parameters extracted by NRW method for a normal incidence and d is the size of the same one). On the other hand, the structure is analyzed like a FSS with the same performance characteristics of a Coherently Radiating Periodic Structure – CORPS, in which the elements are separated approximately by g and the periodicity in the horizontal plane assures that coupling (coherent in this case) between all elements in each layer of the structure, contributes positively to radiation in normal direction. The applications of this novel CORPS structure go from satellite/terrestrial imaging systems, thanks to the possibility to define highly directive beams quite close each other; to Arrays when doing use of their qualities of periodicity, filtrate and coherently coupling.
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Trabajo presentado a la 20th International Conference on Infrared and Millimeter Waves. Orlando (Estados Unidos), 1995.
Trabajo presentado a la 21st International Conference on Infrared and Millimeter Waves. Berlin, 1996.
Trabajo presentado al ISRAMT’99. 7th International Symposium on Recent Advances in Microwave Technology. Malaga, 1999.
Trabajo presentado al 26th ESA Antenna Technology Workshop on Satellite Antenna Modelling and Design Tools. Holanda, 2003.
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Trabajo presentado al XI Simposium de la Union Cientifica Internacional de Radio (URSI'96). Madrid, 1996.
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Trabajo presentado a la 20th International Conference on Infrared and Millimeter Waves. Orlando (Estados Unidos), 1995.
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Trabajo presentado al XX Symposium de la Union Cientifica Internacional de Radio (URSI’05). Gandia, 2005.
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Trabajo presentado al XX Symposium de la Union Cientifica Internacional de Radio (URSI'05). Gandia, 2005.