Suchergebnisse

This contribution focuses on the limitations of Fourier-based imaging when applied to subsampled arrays used in multistatic millimeter-wave radar systems. The aim is to determine the relationship between the size of the object under test (OUT), its position with respect to the radar aperture, and the sampling requirements on the aperture so as to recover aliasing-free images. Based on the analysis results, a method for recovering spectral information is proposed, the idea of which is to replicate the plane wave spectrum, and then apply a band-pass filter defined by a priori knowledge of the OUT size. For simplicity, the analysis is done in two-dimensional (2-D; range and cross-range dimensions). A simulation-based application is presented for validation purposes ; Ministerio de Economía y Competitividad, Gobierno de España, National Research and Development Program under Projects TEC2011-28683-C02-02, TEC 2014- 54005-P ("MIRIIEM"), TEC 2014-55290-JIN ("PORTEMVISION"), and Terasense CSD2008-00068 (Consolider-Ingenio 2010); in part by the Spanish Government under Project TACTICA; in part by the European Regional Development Fund (FEDER); in part by the Galician Regional Government under projects CN2012/279, CN2012/260 (AtlantTIC), and Plan I2C (2011– 2015); and in part by the Gobierno del Principado de Asturias under project GRUPIN14-114

IEEE International Symposium on Antennas and Propagation & USNC/URSI National Radio Science Meeting ( 2018. Boston) ; In this work, array optimization for an imaging system demonstrator is presented. It is able to create 3D images of people as they walk through the scanner and it makes use of a very low number of transceivers. The array positions have been optimized to minimize grating lobes and maximize resolution for a given number of array elements. ; This work is partially supported by the Spanish National Research and Development Program project TEC2015-73908-JIN and RYC-2016-20280, by the European Regional Development Fund (ERDF), and by the Galician Government under project GRC2015/018 and agreement for funding AtlantTIC.

European Conference on Antennas and Propagation (EuCAP 2018) (12th. 2018. London) ; The main goal of this contribution is to provide an overview of an Unmanned Aerial System for Antenna Measurement (UASAM), which will be presented at the AMTA Scientific Workshop on "UAV-based Antenna and Field Measurements". UASAM is a compact low-cost system that can be used for in-situ antenna measurement and diagnostics. It makes use of a Real Time Kinematik (RTK) and a laser altimeter to georefer the measurements with cm-level accuracy. Field radiated by the Antenna Under Test (AUT) is measured with a low-cost power detector at several acquisition surfaces (even non-canonical surfaces) around the AUT (in the near field region). Next, an iterative phase retrieval technique is applied, being able to recover the AUT aperture fields. Furthermore, from these fields, Near-Field to Far-Field (NF-FF) transformation can be used to retrieve the radiation pattern. Several application examples for different kinds of AUTs will be shown in the workshop. In addition, the impact of positioning and geo-referring accuracy will be discussed as well. This system is of great interest for those industrial applications where antenna diagnostics and radiation pattern assessment capabilities are required (e.g. analysis of antenna arrays, tilt testing of base station antennas, etc.) avoiding the need of stopping operational conditions. ; This work has been partially supported by the "Ministerio de Economía y Competitividad" of Spain/FEDER under projects TEC2014-55290-JIN (PORTEMVISION) and TEC2014-54005-P (MIRIIEM); by the "Ministerio of Educación y Cultura" of Spain under FPU grant FPU15/06341; ´ and by the Government of Asturias under project GRUPIN 14-114.

This work develops compressed sensing techniques to improve the performance of an active three dimensional (3D) millimeter wave imaging system for personnel security screening. The system is able to produce a high-resolution 3D reconstruction of the whole human body surface and reveal concealed objects under clothing. Innovative multistatic millimeter wave radar designs and algorithms, which have been previously validated, are combined to improve the reconstruction results over previous approaches. Compressed Sensing techniques are used to drastically reduce the number of sensors, thus simplifying the system design and fabrication. Representative simulation results showing good performance of the proposed system are provided and supported by several sample measurements ; This work was supported in part by CenSSIS, the Gordon Center for Subsurface Sensing and Imaging Systems NSF ERC Program (Award number EEC-9986821); by the Science and Technology Directorate, U.S. Department of Homeland Security under the Award Number 2008-ST-061-ED0001; by the Xunta de Galicia under Plan I2C (2011-2015); by the European Union - FP7 under the project 600849 (INSIDDE); and in part by the Ministerio de Economía y Competitividad of Spain/FEDER under projects CONSOLIDER-INGENIO CSD2008-00068 (TERASENSE), and TEC2011-24492/TEC (iSCAT)

European Radar Conference (EuRAD) (15th. 2018. Madrid) ; This contribution introduces a novel airborne system for subsurface sensing and imaging applications. The system consists of a Ground Penetrating Radar (GPR) mounted on an Unmanned Aerial Vehicle (UAV). Since the system does not need to be in contact with the soil, it is particularly useful for some Non-Destructive Testing (NDT) applications such as landmine detection or archeological surveys. An overview of the system and some of the first flight tests are shown in this contribution. The results of these flight tests prove the feasibility of the system to detect both metallic and dielectric targets. Furthermore, since the system includes a high-accuracy positioning system, measurements could be coherently combined to improve the radar image resolution. ; This work has been partially supported by Government of Spain under projects TEC2014-55290-JIN (PORTEMVISION) and TEC2015-73908-JIN, and grants RYC-2016-20280 and FPU15/06341; by the Gobierno del Principado de Asturias through IDI/2017/000095; and by the Galician Regional Government under project GRC2015/018 and under agreement for funding AtlantTIC.

This paper presents a novel system to obtain images from the underground based on ground penetrating radar (GPR). The proposed system is composed by a radar module mounted on board an unmanned aerial vehicle (UAV), which allows the safe inspection of dif cult-to-access areas without being in direct contact with the soil. Therefore, it can be used to detect dangerous buried objects, such as landmines. The radar measurements are coherently combined using a synthetic aperture radar (SAR) algorithm, which requires cm-level accuracy positioning system. In addition, a clutter removal technique is applied to mitigate the re ection at the air-soil interface (which is caused by impedance mismatching). Besides the aforementioned advantages, the system can detect both metallic and dielectric targets (due to the use of a radar instead of a metal detector) and it allows to obtain high-resolution underground images (due to the SAR processing). The algorithms and the UAV payload are validated with measurements in both controlled and real scenarios, showing the feasibility of the proposed system. ; This work was supported in part by the Ministerio de Economía y Competitividad-Gobierno de España under Project TEC2014-54005-P (MIRIIEM), Project TEC2014-55290-JIN (PORTEMVISION), Project TEC2015-73908-JIN, Project TEC2015-65353-R, and Project RYC-2016-20280, in part by the Ministerio de Educación-Gobierno de España under Grant FPU15/06341, in part by the Gobierno del Principado de Asturias under Grant PCTI 2013-2017, Grant FC-15-GRUPIN14-114, and Grant IDI/2017/000095, and in part by the Galician Regional Government under Project GRC2015/018 and under agreement for funding AtlantTIC (Atlantic Research Center for Information and Communication Technologies). And by the Instituto Universitario de Tecnología Industrial de Asturias (IUTA).

IEEE International Symposium on Antennas and Propagation and USNC-URSI Radio Science Meeting (2018) ; In this contribution, a novel subsurface imaging system to detect buried targets is presented. It is mainly composed by a Ground Penetrating Radar (GPR) mounted onboard an Unmanned Aerial Vehicle (UAV). Thus, the system can be used to inspect areas without being in contact with the soil, which makes it useful for detecting dangerous objects, such as landmines. The system architecture and some of the first prototype measurements, which are post-processed using a Synthetic Aperture Radar (SAR) algorithm, are presented in this contribution. ; This work has been supported by Government of Spain (under projects TEC2014-55290-lIN, TEC2015-73908-lIN and grant FPUI5/06341), Government of Asturias (IDI/2017/000095) and Galician Government (under project GRC2015/018) and under agreement for funding AtlantTIC.

Congreso Nacional de I+d en Defensa y Seguridad (6th. 2018. Valladolid) ; En esta contribución se presentan dos sistemas para inspección no destructiva basados en el empleo de sensores de radiofrecuencia embarcados en vehículos aéreos no tripulados (UAVs, Unmanned Aerial Vehicles). La tecnología desarrollada permite aprovechar las propiedades de las ondas electromagnéticas como, por ejemplo, la capacidad de penetración en ciertos materiales. Ello hace posible detectar fenómenos que no podríamos ver con nuestros propios ojos ni con las cámaras habitualmente embarcadas en UAVs (de ahí el nombre de aplicaciones "más allá de lo visible"). Los sistemas presentados son: GEODRON, que cuenta con un georradar (o GPR, Ground Penetrating Radar) embarcado y permite obtener imágenes de alta resolución del subsuelo y de los objetos enterrados en él; y UASAM, que incorpora un detector de potencia de radiofrecuencia y posibilita la medida de antenas in-situ y la detección de fallos en las mismas. El sistema GEODRON es de especial interés en el ámbito de la seguridad y defensa (para detección de explosivos, como minas antipersona) y en tareas de búsqueda y rescate (para detectar personas atrapadas tras un desastre natural). Al estar el radar embarcado en un UAV, se evita el contacto físico con el suelo durante la exploración, garantizando la seguridad en la operación. Por otro lado, UASAM puede aplicarse también en el ámbito de defensa para, por ejemplo, inspeccionar antenas a bordo de embarcaciones militares. El empleo de UAVs posibilita la inspección de zonas de difícil acceso de forma rápida, lo que supone una gran ventaja en este tipo de aplicaciones. ; Este trabajo ha sido parcialmente financiado por el Gobierno de España (TEC2014-55290-JIN, TEC2015-73908-JIN, RYC-2016-20280, FPU15-06341), el Gobierno del Principado de Asturias (FC- 15-GRUPIN14-114, IDI/2017/000095), el Gobierno de Galicia (GRC2015/018) y AtlantTIC.

This work was supported in part by the Ministerio de Economía, Industria y Competitividad, Gobierno de España of Spain/FEDER, under Project TEC2014-54005-P (MIRIIEM), Project TEC2015-73908-JIN, Project TEC2014-55290-JIN (PORTEMVISION), and Grant FPU15/06341, in part by the Principado de Asturias, through the Plan de Ciencia, Tecnología e lnnovación 2013–2017, under Project GRUPIN14-114, and in part by the Galician Regional Government and the Plan I2C (2011–2015) under Project CN2012/279 and Project CN2012/260 (AtlantTIC).

This paper presents a novel interrogation system that combines multiple millimeter wave transmitters and receivers to create real-time high-resolution radar images for personnel security screening. The main novelty of the presented system is that the images can be created as the person being screened continuously moves across a corridor where the transmitters and receivers, working in a fully coherent architecture, are distributed. As the person moves, the transmitters and receivers are sequentially activated to collect data from different angles to inspect the whole body. Multiple images, similar to video frames, are created and examined to look for possible anomalies such as concealed threats. Two-dimensional (2-D) and three-dimensional (3-D) setups have been simulated to show the feasibility of the proposed system. The simulation results in 2-D have been validated using measurements ; Ministerio de Ciencia e Innovacin of Spain/FEDER under project MIRIIEM-TEC2014-54005-P, in part by the Gobierno del Principado de Asturias through the PCTI 2013-2017, GRUPIN14-114, in part by the Spanish Government under project TACTICA, in part by the European Regional Development Fund (ERDF), in part by the Galician Regional Government under Projects CN2012/279, CN2012/260 (AtlantTIC) and the Plan I2C (2011–2015), and in part by the Science and Technology Directorate, U.S. Department of Homeland Security under the Award Number 2008-ST-061-ED0001