Espacio
URI permanente para esta comunidadhttps://inta.metricsalad.com/handle/123456789/47
En el ámbito espacial, El INTA tiene una gran experiencia en el desarrollo de programas espaciales y pequeños satélites. En sus instalaciones y laboratorios se investiga en tecnologías para el desarrollo de instrumentación espacial, para su posterior implementación en satélites y vehículos espaciales de todo tipo, en colaboración con la ESA y la NASA.
También gestiona y controla en colaboración con la ESA y la NASA, a través de las estaciones espaciales, proyectos de observación de la Tierra, seguimiento y control de vehículos espaciales, sistemas de alerta y salvamento y observación y estudio del Sistema Solar y el espacio profundo, así como control, procesado y diseminación de datos de satélite en el marco del Programa Nacional de Observación de la Tierra por Satélite (PNOTS), en el Centro Espacial INTA-Torrejón.
El INTA contribuye al desarrollo de tecnologías de cargas útiles, sobresaliendo en campos como electromagnetismo computacional y aplicado en radiofrecuencia y microondas, operaciones en misiones espaciales, instrumentación óptica y desarrollo de sensores compactos para exploración planetaria, desarrollo de tecnologías cuánticas, investigación y desarrollo de sistemas de pequeñas plataformas.
En relación al medio ambiente y el cambio climático, el INTA promueve nuevas tecnologías en estudios de la Antártida y el Ártico, encaminadas a desarrollar sensores para la observación de la Tierra y de la atmósfera. En la actualidad desarrolla programas y equipos para la recepción y procesamiento de datos obtenidos desde satélites y otras misiones espaciales.
Todas estas líneas de investigación y desarrollo se materializan a través de proyectos, financiados con fondos propios y con fondos externos , como ANSER (Constelaciones de Pequeños Satélites), PILUM (un lanzador para órbita de nano satélites desde un avión de caza), MARSCONNECT (instrumentación atmosférica compacta para la exploración de Marte), COMUNICACIONES CUÁNTICAS (demostrador en órbita de comunicaciones cuánticas entre pequeños satélites), etc..
Dentro del ámbito de las Misiones Espaciales, el INTA participa en la misión PLATO (PLAnetary Transits and Oscillation of stars) tercera misión de tamaño medio del programa científico de la ESA (Cosmic Vision) con una vida útil de 6 años. Estará dedicado al estudio detallado de sistemas exoplanetarios (incluyendo la detección de más de 10 planetas tipo terrestre en la zona de habitabilidad de estrellas de tipo solar) y al estudio astrosismológico de la estrella central.
Buscar
Examinando Espacio por Título
Mostrando 1 - 20 de 193
- Resultados por página
- Opciones de ordenación
Publicación Restringido A Comparative Study on HCN Polymers Synthesized by Polymerization of NH4CN or Diaminomaleonitrile in Aqueous Media: New Perspectives for Prebiotic Chemistry and Materials Science(Chemistry Europe: European Chemical Societies Publishing, 2019-08-02) Ruiz Bermejo, Marta; De la Fuente, J. L.; Carretero González, J.; García Fernández, L.; Rosa Aguilar, M.; Agencia Estatal de Investigación (AEI); Unidad de Excelencia Científica María de Maeztu Centro de Astrobiología del Instituto Nacional de Técnica Aeroespacial y CSIC, MDM-2017-0737HCN polymers are a group of complex and heterogeneous substances that are widely known in the fields of astrobiology and prebiotic chemistry. In addition, they have recently received considerable attention as potential functional material coatings. However, the real nature and pathways of formation of HCN polymers remain open questions. It is well established that the tuning of macromolecular structures determines the properties and practical applications of a polymeric material. Herein, different synthetic conditions were explored for the production of HCN polymers from NHCN or diaminomaleonitrile in aqueous media with different concentrations of the starting reactants and several reaction times. By using a systematic methodology, both series of polymers were shown to exhibit similar, but not identical, spectroscopic and thermal fingerprints, which resulted in a clear differentiation of their morphological and electrochemical properties. New macrostructures are proposed for HCN polymers, and promising insights are discussed for prebiotic chemistry and materials science on the basis of the experimental results.Publicación Restringido A New Large-Scale Map of the Lunar Crustal Magnetic Field and Its Interpretation(Advancing Earth and Space Science AGU, 2021-02-23) Hood, L. L.; Torres, C. B.; Wieczorek, Mark A.; Stewart, S. T.; Oliveira, Joana S.; National Aeronautics and Space Administration (NASA)A new large-scale map of the lunar crustal magnetic field at 30 km altitude covering latitudes from 65°S to 65°N has been produced using high-quality vector magnetometer data from two complementary polar orbital missions, Lunar Prospector and SELENE (Kaguya). The map has characteristics similar to those of previous maps but better resolves the shapes and distribution of weaker anomalies. The strongest group of anomalies is located on the northwest side of the South Pole-Aitken basin approximately antipodal to the Imbrium basin. On the near side, both strong isolated anomalies and weaker elongated anomalies tend to lie along lines oriented radial to Imbrium. These include named anomalies such as Reiner Gamma, Hartwig, Descartes, Abel, and Airy. The statistical significance of this tendency for elongated anomalies is verified by Monte Carlo simulations. Great circle paths determined by end points of elongated anomaly groups and the locations of five individual strong anomalies converge within the inner rim of Imbrium and intersect within the Imbrium antipode zone. Statistically significant evidence for similar alignments northwest of the Orientale basin is also found. The observed distribution of anomalies on the near side and the location of the strongest anomaly group antipodal to Imbrium are consistent with the hypothesis that iron from the Imbrium impactor was mixed into ejecta that was inhomogeneously deposited downrange in groups aligned radial to the basin and concentrated antipodal to the basin.Publicación Restringido A New Single-Sensor Magnetic Field Gradiometer(Igneta Connect, 2009-08-13) Lucas, I.; Díaz Michelena, M.; De Manuel, V.; Plaza, J. A.; Duch, M.; Esteve, J.; Guerrero, H.In this work a magnetic field gradiometer device has been developed. This device is not composed by two sensors separated a certain distance but by a single-sensor device which measures the real gradient value just at the point where it is wanted to be measured. The experimental set-up consists of a sensor head (a membrane with a fixed permanent magnet on it) vibrating at its resonance frequency, due to an alternating magnetic field gradient. Detection is performed using an optoelectronic method. Two different measurement techniques have been used: frequency measurements (the resonance frequency is measured for every external magnetic field gradient value) and amplitude measurements (the signal amplitude is measured without changing the resonance frequency obtained without an external magnetic field gradient applied). The mechanical stresses of the membrane are related with the dependence of both magnitudes (frequency and amplitude) on the external magnetic field gradient. The minimum and maximum value of the resonance frequency and signal amplitude respectively, correspond with magnetic forces equal to the magnet weight of the sensor head. This prototype shows a noise-limited sensitivity of 2 Gauss/m/√Hz at zero gradient. This device could be used also as a magnetic susceptometer.Ítem Acceso Abierto A Novel Design of Deep Space 25KW Water-cooled Feeder at X-band and High Power Test Campaign Aspects(Universidad Politécnica de Valencia, 2017-04-06) Dragas, Sasa; Mediavilla, Ángel; Tazón, Antonio; Baquero, Pedro; Valle, José; Mandado, Emilio; Vicente, Carlos; Cano, Eduardo; Sanz Contreras, Miguel Ángel; García Patrón Mendiburu, Martín; Ministerio de Ciencia e Innovación (MICINN)Future deep-space missions will generate increasing quantities of data from hundreds of millions of kilometres, requiring much higher RF power level as well as higher frequency bands to increase data transmission capacity. The European Space Agency (ESA) operates a network S/X/Ka-band antennas for Telemetry, Tracking and Command (TT&C) operations of different categories of spacecraft. Present ESA Deep Space Stations are (DSS) equipped with a 20 KW X Band High Power Amplifier (HPA). Future missions will demand larger uplink power levels, for distant spacecraft or for critical phases like entry descending and landing or for emergency situations of missions. This paper presents a part of the work done in the frame of an ESA TRP activity "X-band Cryogenic Feed Prototyping". The emphasis is given on development of the transmitting part that has to deal with minimum 25KW of RF power as well as on the preparation of the testing campaign. In order to prove target properties of the feeder, as a main task appears definition of the corona discharge and power handling test. A novel feeder concept is applied and developed with objective to provide a compact solution that offers superior properties as well as a simple interface with cryogenic receiver. The RF design of the feeder components is refined using SPARK3D software to assure absence of the corona discharge under operational conditions. The transmitting part of the feeder shall be equipped with fully integrated and efficient water-cooling system maintaining the complete system on the optimal temperature. The envisaged tests shall be performed in pressurized chamber with 1KW RF power.Publicación Acceso Abierto A novel induction-based device for the measurement of the complex magnetic susceptibility(Elsevier, 2017-08-13) Díaz Michelena, M.; Mesa Uña, José Luis; Pérez jiménez, M.; Maicas Ramos, M. C.; Cobos Arribas, P.; Hernández Ros, C. A.; European Research Council (ERC)A device named magnetic susceptometer for a complete determination of the magnetic complex susceptibility of materials and minerals has been conceived and manufactured as a complement for the in situ characterization of rocks during high resolution magnetic prospections. In this work a device and its capabilities for susceptibility measurements are described, the calibration performed with artificial samples, and the values of real and imaginary susceptibility of natural samples in a range comprising: χ = 10−4 to 10−7 [SI], representative of Earth and also Mars rocks.Publicación Restringido A Sol–Gel based magneto-optical device for the NANOSAT space mission(Springer Link, 2009-03-31) Zayat, M.; Pardo, R.; Rosa, G.; Del Real, R. P.; Díaz Michelena, M.; Arruego, I.; Guerrero, H.; Levy, D.On December 2004, the Spanish Space Agency INTA (Instituto Nacional de Técnica Aeroespacial) launched the first nanosatellite called NANOSAT (Fig. 1) on board an European rocket Ariane 5, from the French Guyana. The satellite consists of a hexagonal device of <19 kg of weight with a diameter of about 50 cm, which describes a LEO orbit of 655 km of altitude. The main objective of the satellite is to probe the operation and performance of micro- and nanotechnologies in space environment. One of the scientific experiments implemented on board was the Sol–Gel based magnetic nanosensor.Publicación Restringido A study of the optical properties of photopolymer Fabry-Perot microcavities by a dual-wavelength fibre optic architecture(IOP Science Publishing, 2002-06-20) López Heredero, R.; Martín, S.; Fernández de Caleya, R. F.; Lobo Ribeiro, A. B.; Araújo, F. M.; Ferreira, L. A.; Santos, J. L.; Guerrero, H.; 0000-0002-7047-0273; 0000-0002-2988-1222; 0000-0003-2922-3489; 0000-0002-2197-8388; 0000-0002-0818-4268We present a novel method to study the behaviour of the optical properties of photopolymer materials with temperature. The photopolymer is deposited on the tip of optical fibres by dip coating to fabricate low-finesse Fabry-Perot microcavities. The signal processing technique utilized to interrogate the cavity is based on the generation of two quadrature phase-shifted interferometric signals using two Bragg fibre gratings. This technique enables the determination of the values of the thermo-optical coefficient and the linear coefficient of thermal expansion of the photopolymer. The effectiveness of the processing technique is also exploited in the study of the dependence of the temperature sensitivity on the cavity thickness.Publicación Acceso Abierto A Subcell Finite-Difference Time-Domain Implementation for Narrow Slots on Conductive Panels(Multidisciplinary Digital Publishing Institute (MDPI), 2023-08-03) Ruiz Cabello Núñez, M. D.; Martín Valverde, A. J.; Plaza Gallardo, B.; Frövel, M.; Poyatos Martínez, D.; Rubio Bretones, Amelia C.; Gascón Bravo, Alberto; García, S. G.; Instituto Nacional de Técnica Aeroespacial (INTA); Ministerio de Ciencia e Innovación (MICINN)Efficiently modeling thin features using the finite-difference time-domain (FDTD) method involves a considerable reduction in the spatial mesh size. However, in real-world scenarios, such reductions can lead to unaffordable memory and CPU requirements. In this manuscript, we present two stable and efficient techniques in FDTD to handle narrow apertures on conductive thin panels. One technique employs conformal methods, while the other utilizes subgridding methods. We validate their performance compared to the classical Gilbert-Holland model and present experimental results in reverberation environments to shed light on these models’ actual confidence margins in real electromagnetic compatibility (EMC) scenarios.Ítem Restringido Adaption of Magnetic Cleanliness Facilities and Procedures to Overcome the New Challenges of the Scientific Missions(Institute of Electrical and Electronics Engineers, 2019-05-21) Díaz Michelena, M.; Rivero, M. A.; De Frutos, J.; Ordoñez Cencerrado, Amanda A.; Agencia Estatal de Investigación (AEI); European Research Council (ERC)Scientific goals in magnetometry require extremely high resolution magnetometers, a very good program of magnetic cleanliness and a powerful processing methodology. When magnetic cleanliness reaches its limits the exhaustive characterisation of the magnetic signature of the different subsystems together with compensation systems (HW) and algorithms (SW) may be the only way to achieve the performance demanded by the scientific objectives. Furthermore, exploration horizons, only within the limits of our Solar System, present scientific challenges in harsh conditions which comprise, among others, extreme swings of temperature. The magnetic properties of materials depend on temperature and the electrical resistance of wires and coils too. Therefore in wide temperature ranges the behaviour of the magnetic signature with temperature needs to be analysed, minimized when possible, and introduced in the retrieval algorithms for an optimal response. The requirements for the subsystems are present in their testing route documentation. However there are not standards or norms with the established procedures to develop these tests. In this work the INTA Space Magnetism Laboratory will overview different methodologies implemented for standard tests, will introduce some of the upcoming and challenging requirements and will present some of the solutions implemented.Publicación Restringido Adsorption of water on porous Vycor glass studied by ellipsometry(OSA (The Optical Society) Publishing, 2001-02-01) Álvarez Herrero, A.; López Heredero, R.; Bernabeu, E.; Levy, D.; 0000-0002-8462-0156; 0000-0002-2197-8388; 0000-0002-8957-5745; 0000-0001-9228-3412The variation of the optical properties of porous Vycor glass (Corning, Model 7930) under different relative-humidity conditions was studied. The adsorption of water into the glass pores was investigated with spectroscopic ellipsometry. The change of the refractive index was Δn ∼ 0.04 between 5% and 90% relative humidity. A linear relation between the ellipsometer parameter tan Ψ, the amount of water adsorbed in the glass pores, and information about the pore-size distributions was established. The results are in accord with the values obtained from N2 isotherms, transmission electron microscope micrographs, and the manufacturer’s specifications (radius of ∼20 Å). The possibility of using this material as a transducer for implementation in a fiber-optic sensor to measure humidity was evaluated.Publicación Acceso Abierto Aerosol radiative impact during the summer 2019 heatwave produced partly by an inter-continental Saharan dust outbreak – Part 1: Short-wave dust direct radiative effect(European Geoscience Union (EGU), 2021-04-30) Córdoba Jabonero, C.; Sicard, M.; López Cayuela, M. A.; Ansmann, A.; Comerón, A.; Zorzano, María Paz; Rodríguez Gómez, A.; Muñóz Porcar, C.; Ministerio de Ciencia e Innovación (MICINN); Agencia Estatal de Investigación (AEI); European Research Council (ERC); Instituto Nacional de Técnica Aeroespacial (INTA); Ministerio de Economía y Competitividad (MINECO); Córdoba Jabonero, C. [0000-0003-4859-471X]; Sicard, M. [0000-0001-8287-9693]; López Cayuela, M. A. [0000-0002-8825-830X]; Comerón, A. [0000-0001-6886-3679]; Rodríguez Gómez, A. [0000-0002-9209-0685]; Unidad de Excelencia Científica María de Maeztu Grupo de investigación en Teledetección, Antenas, Microondas y Superconductividad UNIVERSITAT POLITECNICA DE CATALUNYA, MDM-2016-0600; Unidad de Excelencia Científica María de Maeztu Centro de Astrobiología del Instituto Nacional de Técnica Aeroespacial y CSIC, MDM-2017-0737The short-wave (SW) direct radiative effect (DRE) during the summer 2019 heatwave produced partly by a moderate, long-lasting Saharan dust outbreak over Europe is analysed in this study. Two European sites (periods) are considered: Barcelona, Spain (23–30 June), and Leipzig, Germany (29 and 30 June), 1350 km apart from each other. Major data are obtained from AERONET and polarised Micro-Pulse Lidar (P-MPL) observations. Modelling is used to describe the different dust pathways, as observed at both sites. The coarse dust (Dc) and fine dust (Df) components (with total dust, DD = Dc + Df) are identified in the profiles of the total particle backscatter coefficient using the POLIPHON (POlarisation LIdar PHOtometer Networking) method in synergy with P-MPL measurements. This information is used to calculate the relative mass loading and the centre-of-mass height, as well as the contribution of each dust mode to the total dust DRE. Several aspects of the ageing of dust are put forward. The mean dust optical depth and its ratios are, respectively, 0.153 and 24 % in Barcelona and 0.039 and 38 % in Leipzig; this Df increase in Leipzig is attributed to a longer dust transport path in comparison to Barcelona. The dust produced a cooling effect on the surface with a mean daily DRE of −9.1 and −2.5 W m−2, respectively, in Barcelona and Leipzig, but the DRE ratio is larger for Leipzig (52 %) than for Barcelona (37 %). Cooling is also observed at the top of the atmosphere (TOA), although less intense than on the surface. However, the DRE ratio at the TOA is even higher (45 % and 60 %, respectively, in Barcelona and Leipzig) than on the surface. Despite the predominance of Dc particles under dusty conditions, the SW radiative impact of Df particles can be comparable to, even higher than, that induced by the Dc ones. In particular, the DRE ratio in Barcelona increases by +2.4 % d−1 (surface) and +2.9 % d−1 (TOA) during the dusty period. This study is completed by a second paper about the long-wave and net radiative effects. These results are especially relevant for the next ESA EarthCARE mission (planned in 2022) as it is devoted to aerosol–cloud–radiation interaction research.Publicación Restringido Anisotropic magnetoresistance (AMR) instrument to study the Martian magnetic environment from the surface: expected scientific return(Springer Link, 2023-08-15) Díaz Michelena, M.; Fernández Romero, S.; Adeli, Solmaz; Henrich, Clara; Aspás, Alberto; Parrondo, M. C.; Rivero Rodríguez, Miguel Ángel; Oliveira, Joana S.; Instituto Nacional de Técnica Aeroespacial (INTA); Centros de Excelencia Severo Ochoa, BARCELONA SUPERCOMPUTING CENTER (BSC), SEV2015-0493The ExoMars programme has the objective to answer to the question of whether life ever existed on Mars. The second mission comprising the Rosalind Franklin rover and Kazachok Surface Platform was designed to focus specifically on the characterization of the environmental parameters which can play an important role for the existence of life on the surface of the planet. One of these parameters is the magnetic field because of its ability of shielding the solar and cosmic radiation. For such characterization, the scientific suite of the Surface Platform counts with two instruments: the Anisotropic MagnetoResistance (AMR) and the MArtIan Ground ElectromagneTic (MAIGRET) instruments. The AMR goal is to characterize both the surface and subsurface and the time-varying magnetic fields, related to the crustal and the external fields respectively, at the ExoMars landing site in Oxia Planum. The operation to achieve these goals includes two phases, the first phase corresponding to the lander descent and the second phase in which the instrument is deployed on the surface. In this work, we simulate the first operations phase using synthetic magnetic field models, assuming that the different crustal units at the landing site might be magnetized. We also perform measurements in our laboratory to simulate the second phase operation of the instrument on the Martian surface. We discuss the capability of interpretation of the instrument, based on the available information of the landing site and the results from our models.Ítem Restringido Aplicación de técnicas de impresión 3D al diseño y fabricación de superficies selectivas en frecuencia(Universidad de Sevilla, 2019-09-06) Muñoz Rebate, I.; Martín Iglesias, S.; Plaza Gallardo, B.; Poyatos Martínez, D.; Agencia Estatal de Investigación (AEI)This paper presents the application of 3D printing (or additive manufacturing) to the design and fabrication of a frequency selective surface (FSS). In particular, the periodic structure has been created using fused deposition modeling (FDM) technology. Along the paper, a complete development method is described, starting from the electromagnetic (EM) characterization of available materials and the selection of the most suitable one, followed by the design, analysis and optimization of the geometry via EM simulations. Finally a test specimen is implemented and measured in an anechoic chamber. In this case, an innovative material is used: a graphene filled thermoplastic that is able to conduct electricity. The measurement results agree with the simulations, validating the approach and encouraging the use of this 3D printing technique for the manufacturing of radiofrequency devices.Publicación Restringido Application of a Spherical Multi-Purpose Facility to the Selection of the Appropriate Radome for an On-Board POD Antenna(Taylor and Francis Online, 2012-04-03) Poyatos Martínez, D.; Escot Bocanegra, D.; De Diego Custodio, E.; González Diego, I.; Sáez de Adana, F. M.; Montiel, I.; Instituto Nacional de Técnica Aeroespacial (INTA)This paper presents the application of a new multi-purpose facility for electromagnetic tests to the measurement of the influence of radomes on the radiation of an antenna. The antenna under test is part of a project for mounting a small, low-cost, low-power electronic system in the pod of an unmanned aerial vehicle. The shape of the radome is restricted to the pod physical specifications, but several materials could be tested to assess its effect on the antenna, and to select the best fitted for this particular application.Ítem Restringido Application of Artificial Neural Networks to Complex Dielectric Constant Estimation from Free-Space Measurements(Springer Link, 2009-03-16) Jurado Lucena, A.; Escot Bocanegra, D.; Poyatos Martínez, D.; Montiel, I.; Instituto Nacional de Técnica Aeroespacial (INTA)Adequate characterization of materials allows the engineer to select the best option for each application. Apart from mechanical or environmental characterization, last decades’ rise in the exploitation of the electromagnetic spectrum has made increasingly important to understand and explain the behavior of materials also in that ambit. The electromagnetic properties of non-magnetic materials are governed by their intrinsic permittivity or dielectric constant and free-space measurements is one of the various methods employed to estimate this quantity at microwave frequencies. This paper proposes the application of Artificial Neural Networks (ANNs) to extract the dielectric constant of materials from the reflection coefficient obtained by free-space measurements. In this context, two kind of ANNs are examined: Multilayer Perceptron (MLP) and Radial Basis Function (RBF) networks. Simulated materials are utilized to train the networks with and without noise and performance is tested using an actual material sample measured by the authors in an anechoic chamber.Publicación Restringido Application of FDTD to HRRP Generation of a Cavity Model for NCTI Purposes(Institute of Electrical and Electronics Engineers, 2011-07-04) Fernandez Recio, R.; Escot Bocanegra, D.; Poyatos Martínez, D.; Jurado Lucena, A.; Errasti Alcalá, B.; Montiel, I.; Instituto Nacional de Técnica Aeroespacial (INTA)The application of a time-domain electromagnetic simulation code to a realistic and challenging problem like the high-resolution range profile (HRRP) generation of an inlet cavity model is presented in this paper. HRRPs can be used to accomplish noncooperative target identification (NCTI) of aircrafts by means of radar, and the database needed in this technique tends to be populated with predicted data obtained with software tools. Most codes employed with these purposes are frequency domain methods, which need multiple simulations at different adequately chosen frequencies, as well as some postprocessing, to get a radar signature. Instead, this paper focuses on finite difference time domain (FDTD) analysis of the response of a cavity, because of the relevance of these parts of an aircraft in the overall signature, and numerical results are compared with measurements performed by the authors in an anechoic chamber. This work also shows the advantages of using an electromagnetic code based on time domain for HRRP generation.Ítem Acceso Abierto Application of finite element methods to the analysis of magnetic contamination around electronics in magnetic sensor devices(Institute of Electrical and Electronics Engineers, 2012-05-23) Díaz Michelena, M.; Belén Fernández, A.; Maicas, M.The number of missions devoted to the measurement of the magnetic field has dramatically decreased since the 80s, being the decrease in number accompanied by a reduction in the mass and economic budget of many of the exploration missions. This scenario was the seed for a new generation of sensors: the Commercial Off-The-Shelf (COTS) based microsensors. In the particular case of magnetometers, these miniaturized and compact devices imported a traditional problem of geomagnetic missions: the magnetic cleanliness trouble. Magnetic cleanliness, which is isolated in the platform when the magnetometer is deployed in a boom, becomes a real trouble when it has to be considered at Printed Circuit Board (PCB) level. In this work we present the description, method and results of a finite elements model for an engineering prototype of a NANOSAT-01 two axis magnetic sensor, launched in 2004. The idea is to extrapolate this method for all subsystems of a satellite.Publicación Restringido Application of particle swarm optimization (PSO) to single-snapshot direction of arrival (DOA) estimation(Institute of Electrical and Electronics Engineers, 2007-12-06) Escot Bocanegra, D.; Poyatos Martínez, D.; González, Iván; Sáez de Adana, F.; Cátedra, M. F.; Instituto Nacional de Técnica Aeroespacial (INTA)This paper attempts to examine the feasibility of using an heuristic bio-inspired algorithm in DOA estimation. Specifically, particle swarm optimization (PSO) (Kennedy, et. al., 1995)Publicación Restringido Assessment of FEM simulations in EMC test setups for small aeronautical platforms(Taylor and Francis Online, 2018-08-03) Plaza Gallardo, B.; Ramajo, O.; López, D.; Poyatos Martínez, D.; Escot Bocanegra, D.; Agencia Estatal de Investigación (AEI)The rise of fly-by-wire systems together with the utilization of new composite materials make it more and more difficult to assess and guarantee aircraft electromagnetic compatibility (EMC). As a result, the design phase becomes of paramount importance in the aircraft production process. Performing actual EMC tests over different configurations in such a phase would be very costly and time consuming, so reliable computational techniques are being explored in the last years. However, proper validation is needed in order to gain confidence in the results obtained by simulations. In this regard, this paper presents the assessment of a simulation approach based on the finite element method to reproduce typical setups of an EMC test laboratory for small aeronautical platforms. The final test object is based on an unmanned aerial vehicle but, first, a simpler test case is used to tune and assess the simulation approach. Once the approach is both qualitatively and quantitatively validated with measurements, new setups involving the aeronautical specimen are analysed.Ítem Restringido Assessment of Spectrally Matched Cells(AESS, 2023-10-02) Gras, Ana; Barber, Christopher; Baur, Carsten; Instituto Nacional de Técnica Aeroespacial (INTA)The spectral matching criterion for solar cells is crucial for photovoltaic (PV) measurements under simulated sunlight because it helps reducing the uncertainty due to the spectral mismatch correction. It is common practice in both terrestrial and space PV communities to identify spectrally matched cells as those having spectral responsivities identical or at least very similar to each other. A quantitative definition and evaluation of spectrally matched cells is made in this document.
