(Espacio) Comunicaciones de Congresos

URI permanente para esta colecciónhttps://inta.metricsalad.com/handle/123456789/57

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Micromachined low-finesse Fabry-Perot interferometer for the measurement of low DC electrical currents
(Institute of Electrical and Electronics Engineers, 2002-05-10) López Heredero, R.; Santos, J. L.; Fernández de Caleya, R. F.; Araújo, F. M.; Ferreira, L. A.; Guerrero, H.; Guerrero, H. [0000-0003-2922-3489]; López Heredero, R. [0000-0002-2197-8388]
An optical fiber current sensor based on a permanent magnet fixed on the center of a micromachined Si membrane has been presented. The transducing operation principle is magneto-mechanical and has a linear response. A great improvement of the sensitivity of the microcavities was achieved by the use of a planar coil. Interrogation of the transducer has been carried out using a Fabry-Perot interferometer with an all-fiber detection system to avoid the influence of electromagnetic noise. The effectiveness of a fiber scheme based on the utilization of two fibre Bragg gratings to generate two quadrature phase-shifted interferometric signals has also been reported.
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Complex permittivity estimation by bio-inspired algorithms for target identification improvement
(Springer Link, 2007-05-14) Poyatos Martínez, D.; Escot Bocanegra, D.; Montiel, I.; Olmeda, I.; Instituto Nacional de Técnica Aeroespacial (INTA)
Identification of aircrafts by means of radar when no cooperation exists (Non-Cooperative Target Identification, NCTI) tends to be based on simulations. To improve them, and hence the probability of correct identification, right values of permittivity and permeability need to be used. This paper describes a method for the estimation of the electromagnetic properties of materials as a part of the NCTI problem. Different heuristic optimization algorithms such as Genetic Algorithms (GA) and Particle Swarm Optimization (PSO), as well as other approaches like Artificial Neural Networks (ANN), are applied to the reflection coefficient obtained via free-space measurements in an anechoic chamber. Prior to the comparison with real samples, artificial synthetic materials are generated to test the performance of these bio-inspired algorithms.
Acceso Abierto
Demonstration of the Use of Fiber Bragg Grating for Optical Sensing (FIBOS) during an Aerospace Mission
(SPIE Optical Engineering Applications, 2008-07-26) López Heredero, R.; Frövel, Malte; Maicas, S. S.; García Olcina, R.; Frövel, M. [0000-0001-9447-4036]; López Heredero, R. [0000-0002-2197-8388]; García Olcina, R. [0000-0002-3383-2247]
Fiber Bragg Gratings, FBG, are very appropriate strain and temperature sensors for structural health monitoring of satellite structures. They can be embedded in composite structures and monitor the entire life cycle of a satellite structure from the manufacturing process, to the mechanical and thermal certification tests, the launch loads up to the operative loads in space. The optical device based in two FBGs that will be used to measure temperature and strain during the OPTOS mission is presented. OPTOS is a picosatellite, designed and manufactured by the Spanish Institute for Aerospace Technology, INTA that will be launched at the beginning of 2009. The main goal of the mission is to demonstrate the feasibility of several technologies for space applications inside a miniaturized space and with big restrictions in terms of mass and power consumption. The paper describes the different units that constitute the FIBOS payload: a) one monolithic tunable laser used as light source offering great advantages as wide range of tunability, robustness and fast electronically operation; b) two FBGs that are mounted onto one steel mechanical structure to monitor independently temperature and strain; c) the processing unit that contains the digital electronics that processes the signal produced by the receiver unit, follows the synchronization between the laser source and the receiver and contains the electrical interface with the Electrical Power Subsystem (EPS) and the On-board Data Handling (OBDH) of the satellite.
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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.
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Performance analysis of the Particle Swarm Optimization algorithm when applied to direction of arrival estimation
(Institute of Electrical and Electronics Engineers, 2009-09-18) Errasti Alcalá, B.; Escot Bocanegra, D.; Poyatos Martínez, D.; Montiel, I.; Instituto Nacional de Técnica Aeroespacial (INTA)
Direction of arrival (DOA) estimation is a well known problem involved in different applications. The latest of these applications have greater constraints which make necessary new efforts in estimating the DOA with fewer snapshots. In that sense, this paper presents an iterative method based on particle swarm optimization that solves the problem with a single snapshot. The performance of this algorithm is analyzed and shown with numerical results under different scenarios. Conclusions are also provided.
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RCS measurements and predictions of different targets for radar benchmark purpose
(Institute of Electrical and Electronics Engineers, 2009-09-18) Férnandez Recio, R.; Jurado Lucena, A.; Errasti Alcalá, B.; Poyatos Martínez, D.; Escot Bocanegra, D.; Montiel, I.; Instituto Nacional de Técnica Aeroespacial (INTA)
This paper presents radar cross section (RCS) measurements of different targets suitable for electromagnetic software comparison and validation. The targets have been designed, fabricated and measured at INTA to study different scattering mechanisms such as reflection and diffraction on curved surfaces and edges (truncated cone), reflection and diffraction on planar surfaces and straight wedges (triangular prism) or tip diffraction and travelling waves (conesphere). These measurements can be used as a valuable tool to validate and adjust the input parameters of electromagnetic prediction codes according to the requirements of the engineer.
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Joint Direction of Arrival and amplitude estimation using Particle Swarm Optimization and a single snapshot
(Institute of Electrical and Electronics Engineers, 2010-05-09) Errasti Alcalá, B.; Escot Bocanegra, D.; Poyatos Martínez, D.; Jurado Lucena, A.; Fernández Recio, R.; Instituto Nacional de Técnica Aeroespacial (INTA)
Direction of Arrival (DOA) estimation is a problem which concerns very diverse fields of interest. In most applications, not only the DOA but also the estimation of the amplitude of the incoming signals is becoming an important issue. In that sense, Particle Swarm Optimization (PSO) has shown a great capability to solve the DOA problem accurately and this communication presents a method to estimate both the amplitude and the Direction of Arrival of several incoming signals of a given wavelength.
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Study of the scattering mechanisms of a set of conospheres
(Institute of Electrical and Electronics Engineers, 2010-05-12) Fernández Recio, R.; Jurado Lucena, A.; Errasti Alcalá, B.; Escot Bocanegra, D.; Poyatos Martínez, D.; Instituto Nacional de Técnica Aeroespacial (INTA)
This paper presents Radar Cross Section (RCS) measurements and predictions of a set of three conospheres suitable for electromagnetic software validation. These measurements can be used as a RCS reference data for testing existing and future codes, as well as for the analysis of the scattering mechanisms present in this kind of objects. The association between the scattering mechanism and its response is specially valuable in a validation process, in which simulations and measurements are compared, to identify the possible weak points of the electromagnetic tool.
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Methodology to Achieve Accurate Non Cooperative Target Identification Using High Resolution Radar and a Synthetic Database
(Springer Link, 2010-07-02) Jurado Lucena, A.; Errasti Alcalá, B.; Escot Bocanegra, D.; Fernández Recio, R.; Poyatos Martínez, D.; Montiel, I.; Instituto Nacional de Técnica Aeroespacial (INTA)
In the last few years, there is a great interest in developing an identification system capable to make a reliable classification of aircrafts into different groups (friendly, hostile or neutral). Depending on the context in which these systems are deployed, incorrect identification may lead to serious problems, such as fratricide or engagement of civilian aircrafts. Different techniques have been researched to face this problem, but non-cooperative ones have awakened more interest because they do not require aircraft collaboration. Non Cooperative Target Identification (NCTI) using radar is a complex task, mainly due to the fact that a database of possible targets is needed. To populate this database, Radar Cross Section (RCS) predictions produced by computer simulation seem to be the most feasible way to perform this task, since measurements alone cannot cover the vast range of targets, configurations and required aspect angles. These predictions are typically performed in the frequency domain and a specific processing must be done to obtain both High Resolution Range Profiles (HRRPs) and 2D Inverse Synthetic Aperture Radar (2D-ISAR) images. This paper shows a methodology to face the NCTI task, which use both synthetic HRRPs and 2D-ISAR to achieve an accurate identification.
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.
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Medida y Simulación de la Modulación Producida por el Movimiento de las Palas en la Dispersión Monoestática de una Cavidad
(Universidad Miguel Hernández de Elche, 2012-09-14) Uribe Pérez, N.; Escot Bocanegra, D.; Fernández Recio, R.; Poyatos Martínez, D.; Instituto Nacional de Técnica Aeroespacial (INTA)
The scattering behavior and simulation of cavities are still being studied by several research groups. In this paper, a simplified jet-engine model with eight straight blades and blade motion capability has been designed and manufactured at the National Institute for Aerospace Technology (INTA), Spain and the effect of the motion of the blades has been analyzed. The work carried out can be divided into two parts: measurements of the cavity in the anechoic chamber placed at INTA facilities, and simulations with HFSS, a commercial software for electromagnetic problems.
Acceso Abierto
Tendencias actuales de la lógica reconfigurable en sistema radar
(Universidad de Elche, 2012-09-19) López Rodríguez, P.; Fernández Recio, R.; Bravo, I.; Instituto Nacional de Técnica Aeroespacial (INTA)
Los sistemas radar se caracterizan por la gran cantidad de procesamiento de señal que deben de llevar a cabo para la detección correcta de blancos en el espacio. Los dispositivos de lógica reconfigurable, por su estructura interna y velocidad son óptimos para su utilización en las diferentes etapas de estos sistemas. En este artículo se lleva a cabo un estudio del arte de la aplicación de la lógica reconfigurable en sistemas radar así como un posterior análisis de las etapas más críticas en las que ésta entra en juego.
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Sistema de Medida Polivalente para la Realización de Ensayos de Dispersión Electromagnética y su Aplicación sobre Materiales y Recubrimientos
(Ministerio de Defensa: Secretaria General Técnica, 2013-11-07) Poyatos Martínez, D.; Escot Bocanegra, D.; Aguilar Rosado, Juan Angel; González Diego, I.; Instituto Nacional de Técnica Aeroespacial (INTA)
Una instalación de medida singular e innovadora, concebida para la realización de gran variedad de ensayos electromagnéticos, ha sido diseñada y construida en el Laboratorio de Detectabilidad y Guerra Electrónica del INTA. Dicha instalación, denominada BIANCHA, está basada en un sistema de posicionamiento esférico con capacidad biestática. Además, gracias a un analizador vectorial de redes (VNA) de cuatro puertos y al uso de sondas dualmente polarizadas, se posibilitan ensayos polarimétricos. Con todo ello, BIANCHA es lo suficientemente versátil para permitir que se lleven a cabo en la misma instalación ensayos de absorción y caracterización electromagnética de materiales o ensayos de radiación y dispersión. Así, la comunicación describirá el novedoso concepto de instalación y presentará resultados de medida relativos a la caracterización electromagnética de materiales y recubrimientos no metálicos usados en el ámbito aeronáutico.
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Identificación no cooperativa de blancos reales aéreos mediante radar utilizando una base de datos sintética y descomposición en valores singulares
(Ministerio de Defensa: Secretaria General Técnica, 2013-11-07) López Rodríguez, P.; Fernández Recio, R.; Bravo, I.; De Diego Custodio, E.; Poyatos Martínez, D.; Escot Bocanegra, D.; Instituto Nacional de Técnica Aeroespacial (INTA)
El reconocimiento de blancos aéreos no cooperativos mediante perfiles de alta resolución es un procedimiento de gran interés en el ámbito de la defensa. La creación de la base de datos para el reconocimiento a partir de simulaciones electromagnéticas es un tema recursivo en el mundo de la identificación no cooperativa. Se trata de una solución de bajo coste que permite tener información de todos los posibles blancos, rangos de frecuencia y diferentes ángulos de aspecto. Sin embargo, el uso de simulaciones electromagnéticas como base de datos en el reconocimiento de aviones reales hace del proceso una tarea complicada. Mediante la descomposición en valores singulares de un conjunto de perfiles se consigue la reducción de dimensionalidad añadiendo la capacidad de trabajar en el dominio transformado para realizar el proceso de identificación. La principal dificultad de este estudio estriba en el reconocimiento de medidas reales con la utilización de una base de datos construida sintéticamente mediante simulaciones electromagnéticas de modelos CAD de aeronaves.
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EPOD: Jammer de bajo consumo y coste para UAS y aviones blanco
(Ministerio de Defensa: Secretaria General Técnica, 2013-11-07) De Diego Custodio, E.; Escot Bocanegra, D.; Aguilar Rosado, Juan Angel; González Diego, I.; Instituto Nacional de Técnica Aeroespacial (INTA)
EPOD es el primer sistema de guerra electrónica (jamming) de bajo consumo y coste, específicamente diseñado para UAVs y aviones blanco. El sistema es reconfigurable en vuelo de manera remota, lo que permite la reprogramación de diferentes contramedidas y modos de funcionamiento. Además, está dotado de una gran versatilidad para ser instalado en cualquier UAS. El sistema puede operar con sub-bandas específicas S, C, X, Ku, o multibanda y entre sus modos de operación destacan RGPO, VGPO, control de RCS dinámica y estática, modulaciones vectoriales dinámicas y estáticas reconfigurables y ruido. El bajo peso del sistema completo (como máximo 5Kg de peso, incluidas las baterías) y su fácil y flexible instalación en diversas plataformas aéreas, hacen que dicho equipo de GE sea ideal para su instalación tanto en aviones blanco de prestaciones medias como altas.
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Reflectance of interurban-road pavements from radar-based measurements
(SPIE Digital Library, 2013-11-13) Fernández, Paz; Peña García, A.; Poyatos Martínez, D.; Escot Bocanegra, D.; Fernández Oliveras, A.; Instituto Nacional de Técnica Aeroespacial (INTA)
Reflectance measurements in interurban-road typical pavements are essential for traffic security. The reflectance of interurban-road pavements presents high variability due to such variables as climatic and atmospheric conditions and the presence of foreign materials on the road (e.g. dirt, fuel or oil). For this reason, the recording of real-time measurements for these kinds of pavements is a complex task. However, its critical importance in traffic safety demands precise measurements under all the possible conditions. In this context, the use of remote-sensing systems working in the radar spectral range is of great interest. With active sensors that receive their own radar signal, the reflectance measurements made by the remote-sensing system are not influenced by the atmospheric conditions. In this work, we present a radar-based methodology to develop real-time measurements of the reflectance in typical interurban-road pavements. We are engaged in extending this new method to study the reflectance of interurban-road pavements within the visible spectrum.
Acceso Abierto
Singular Value Decomposition Applied to Automatic Target Recognition with High Resolution Range Profiles
(Multidisciplinary Digital Publishing Institute (MDPI), 2014-01-02) López Rodríguez, P.; Escot Bocanegra, D.; Fernández Recio, R.; Bravo, I.; Instituto Nacional de Técnica Aeroespacial (INTA)
Abstract: With the development of wideband radars new applications have emerged related to this kind of sensor. That is the case of automatic target recognition based on radar imagery. In this paper a target recognition methodology based on one dimensional high resolution radar imagery is presented. 1D radar images, namely high resolution range profiles (HRRP) are comprised of range bins and contain the distribution of the scattering centers of a target providing information about target structure. In this manuscript, identification of HRRP coming from measurements of in-flight aircraft is carried out by comparison with a database of simulated HRRPs. Simulated HRRPs have a very clean signature while actual HRRPs suffer from noise and other unwanted effects making the recognition process an arduous task. In order to overcome the differences between profiles, Singular Value Decomposition (SVD) is applied to matrices of HRRP. SVD is a robust tool for the decomposition of any matrix into orthogonal basis spaces, thus, by applying SVD to the HRRP matrices and selecting the most significant singular vectors, the matrices can be split into a signal and a noise subspace. The identification algorithm proposed in this paper is based on finding the aircraft which minimizes the angle between signal subspaces. Confusion matrices for the classification of the whole test set and error rates obtained will be provided in the paper full-version. As will be shown, the use of SVD provides good recognition rates even the lack of similarity between actual and simulated profiles.
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UAVEMI project: Numerical and experimental EM immunity assessment of UAV for HIRF and lightning indirect effects
(Institute of Electrical and Electronics Engineers, 2016-07-07) García, Salvador G.; Silva, F.; Escot Bocanegra, D.; Pascual, E.; Pantoja, M. F.; Riu, P.; Añón Cancela, M.; Álvarez, J.; Cabello, M.; Pous, M.; Fernández, S.; Trallero, R.; Poyatos Martínez, D.; Nuño, L.; Instituto Nacional de Técnica Aeroespacial (INTA)
The UAVEMI project, funded by the Spanish Ministry of Economy and Competitiveness, gathers a consortium formed by several research and development institutions and one industrial partner. The main goal is to develop innovative experimental and numerical approaches for the assessment of the electromagnetic compatibility of unmanned air vehicles, under high intensity radiated fields, lightning indirect effects and non-nuclear electromagnetic pulses. This contribution describes the capabilities currently being developed under the project.
Acceso Abierto
Ponderación suave de subespacios aplicada a la identificación no cooperativa de blancos aéreos
(Ministerio de Defensa: Secretaria General Técnica, 2016-11-18) Hernán Vega, O.; López Rodríguez, P.; Poyatos Martínez, D.; Escot Bocanegra, D.; Instituto Nacional de Técnica Aeroespacial (INTA)
En las últimas décadas, con el desarrollo de la tecnología, surgen los sistemas radar de alta resolución, dispositivos que permiten obtener imágenes de los diferentes objetos analizados bajo cualquier circunstancia y que por tanto pueden ser utilizados en el contexto de la identificación no cooperativa. Los sistemas de identificación no cooperativa (NCTI) basan su funcionamiento en comparar la firma radar de un blanco iluminado con la firma radar de posibles blancos contenida en una base de datos de referencia. El propósito final es la identificación de aeronaves de manera rápida y fiable implementando un apropiado procesado de la señal recibida. Es por esto por lo que es de gran interés el estudio de un buen método de identificación. Con el fin de obtener la información más significativa del blanco iluminado y mejorar el proceso de identificación, es posible aplicar métodos basados en subespacios. En este estudio se establece la simulación de un sistema de identificación mediante un algoritmo basado en la ponderación suave o softweighting de subespacios. El objetivo de esta comunicación será determinar las similitudes de un conjunto de perfiles de alta resolución (HRRP) de blancos reales con perfiles procedentes de simulaciones electromagnéticas. Considerando las diferencias entre los perfiles estimados y los reales, las altas tasas de identificación obtenidas revelan que la implementación del algoritmo basado en softweighting podría ser una buena opción para su aplicación en un sistema operativo de identificación.
Acceso Abierto
Perfiles de alta resolución biestáticos medidos en la cámara polivalente BIANCHA
(Ministerio de Defensa: Secretaria General Técnica, 2016-11-18) López Rodríguez, P.; Escot Bocanegra, D.; Hernán Vega, O.; Poyatos Martínez, D.; Ministerio de Economía y Competitividad (MINECO)
BIANCHA (BIstatic ANechoic CHAmber) es una instalación singular e innovadora localizada en el Instituto Nacional de T´ecnica Aeroespacial (INTA). Fue concebida para la realización de gran variedad de ensayos electromagn´eticos como medidas de antenas, de firma radar o RCS -Radar Cross Section-, caracterización de materiales, medidas de absorción radar, de radomos y recubrimientos para antenas, etc. BIANCHA se encuentra alojada en el seno de una cámara anecoica, y consiste en una plataforma giratoria y dos brazos elevados capaces de situar dos sondas colocadas en sus extremos en cualquier punto de una semiesfera imaginaria. De este modo, es posible establecer cualquier combinación de ángulos entre estas sondas y el centro de la instalación formándose así un sistema biestático de medida en tres dimensiones. Por otro lado y dentro del presente contexto, al igual que en los sistemas monoestáticos, los radares de alta resolución nos permiten explorar una gran variedad de aplicaciones interesantes en el caso biestático. Un ejemplo de ello es la identificación no cooperativa de blancos, donde se intenta clasificar un blanco observado por comparación de su firma radar con una base de datos. Estas firmas radar pueden ser recogidas de manera biestática y suelen ser de dos tipos, las denominadas perfiles de alta resolución (HRRP), o las conocidas como imágenes radar de apertura sintética inversa (ISAR). Esta comunicación tiene como objetivo presentar la aplicabilidad de BIANCHA para los casos de extracción de firmas radar biestáticas, en donde se presentará el procedimiento de medida y la creación de los perfiles biestáticos correspondientes con diferentes modelos de aeronaves a escala.

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