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2. Facility for Continuous Agricultural Field Monitoring With a GB-PolSAR

Author

Universidad de Alicante. Departamento de Física, Ingeniería de Sistemas y Teoría de la Señal, Universidad de Alicante. Instituto Universitario de Investigación Informática, Mas, Mireia, Aguasca, Albert, Broquetas, Antoni, Fàbregas, Xavier, Mallorquí Franquet, Jordi J., Llop, Jordi, Lopez-Sanchez, Juan M., Kubanek, Julia, Universidad de Alicante. Departamento de Física, Ingeniería de Sistemas y Teoría de la Señal, Universidad de Alicante. Instituto Universitario de Investigación Informática, Mas, Mireia, Aguasca, Albert, Broquetas, Antoni, Fàbregas, Xavier, Mallorquí Franquet, Jordi J., Llop, Jordi, Lopez-Sanchez, Juan M., and Kubanek, Julia

Abstract

Current climate and weather changes urged the scientific community to find ways to observe and understand the relatively rapid land-atmosphere processes related to the water cycle. The HydroSoil project, funded by the European Space Agency, was proposed to experimentally assess the use of Synthetic Aperture Radar in future short revisit time missions based on Geosynchronous Orbital platforms. This paper describes the HydroSoil facility providing continuous monitoring of an agricultural field with a 10-minute temporal resolution and a spatial resolution in the order of 1m2. Gathered data from the full Pol Ground-Based SAR are being used to investigate the capability of Geosynchronous SAR missions to retrieve soil moisture and to measure vegetation parameters. To achieve the project's objectives, intensive procurement of ground truth data encompassing continuous acquisition of relevant meteorological parameters like air humidity, temperature, precipitation wind speed and direction, pressure, and solar irradiation together with other vegetation characteristics under study has been mandatory. The different densities, sizes, and water content of two different crops, barley and corn, together with the data generated, will enable the assessment of the missions' ability to extract essential scene characteristics, such as soil moisture and crop water content, for use in future geostationary missions.

Published
2024

3. Transpolarising Trihedral Corner Reflector Characterisation Using a GB-SAR System

Author

Ferrer, Pere J., Lopez-Martinez, Carlos, Aguasca, Albert, Pipia, Luca, Gonzalez-Arbesu, Jose M., Fabregas, Xavier, and Romeu, Jordi

Subjects
Physics - Instrumentation and Detectors, High Energy Physics - Experiment, A.m
Abstract

The use of a low profile, light weight and easy to fabricate transpolarising surface placed on one side of a trihedral corner reflector (TCR) as polarimetric calibrator is presented in this letter. The transpolarising-TCR (TTCR) presents a high backscattered cross-polar response contrary to standard TCRs. The performance of this device has been tested at X-band using the UPC GB-SAR., Comment: Accepted for publication in IEEE Geoscience and Remote Sensing Letters

Published
2011
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6. Assessment of the Impact of Long Integration Time in Geosynchronous SAR Imagery of Agricultural Fields by Means of GB-SAR Data

Author

Universidad de Alicante. Departamento de Física, Ingeniería de Sistemas y Teoría de la Señal, Universidad de Alicante. Instituto Universitario de Investigación Informática, Aguasca, Albert, Broquetas, Antoni, Lopez-Sanchez, Juan M., Fàbregas, Xavier, Mallorquí Franquet, Jordi J., Mas, Mireia, Universidad de Alicante. Departamento de Física, Ingeniería de Sistemas y Teoría de la Señal, Universidad de Alicante. Instituto Universitario de Investigación Informática, Aguasca, Albert, Broquetas, Antoni, Lopez-Sanchez, Juan M., Fàbregas, Xavier, Mallorquí Franquet, Jordi J., and Mas, Mireia

Abstract

Geosynchronous Synthetic Aperture Radar (GeoSAR) missions offer the advantage of near-continuous monitoring of specific regions on Earth, making them essential for applications that require continuous information. However, wind induced motion along the inherent long integration time can result in image defocusing, with potential degradation of retrieved information. This paper aims to investigate the impact of GEOSAR long integration time in Synthetic Aperture Radar (SAR) imaging and derived products (time series of backscatter and coherence) required to extract agriculture relevant soil or crop parameters of interest. The study is based on the extensive HydroSoil data acquisition campaign carried out over barley and corn crops, funded by the European Space Agency (ESA). The collected raw data are used to synthesize equivalent apertures with integration times of up to 4 hours, similar to those acquired with a GeoSAR. These Ultra Slow apertures facilitate the assessment of the impact of agricultural scene decorrelation on the generation of images with extended integration times.

Published
2023

10. The WISE 2000 and 2001 field experiments in support of the SMOS mission: sea surface L-band brightness temperature observations and their application to sea surface salinity retrieval

Author

Camps, Adriano, Font, Jordi, Vall-llossera, Merce, Gabarro, Carolina, Corbella, Ignasi, Duffo, Nuria, Torres, Francesc, Blanch, Sebastian, Aguasca, Albert, Villarino, Ramon, Enrique, Luis, Miranda, Jorge Jose, Arenas, Juan Jose, Julia, Agusti, Etcheto, Jacqueline, Caselles, Vicente, Weill, Alain, Boutin, Jacqueline, Contardo, Stephanie, Niclos, Raquel, Rivas, Raul, Reising, Steven C., Wursteisen, P., Berger, Michael, and Martin-Neira, Manuel

Subjects
Remote sensing -- Research, Business, Earth sciences, Electronics and electrical industries
Abstract

Soil Moisture and Ocean Salinity (SMOS) is an Earth Explorer Opportunity Mission from the European Space Agency with a launch date in 2007. Its goal is to produce global maps of soil moisture and ocean salinity variables for climatic studies using a new dual-polarization L-band (1400-1427 MHz) radiometer Microwave Imaging Radiometer by Aperture Synthesis (MIRAS). SMOS will have multiangular observation capability and can be optionally operated in full-polarimetric mode. At this frequency the sensitivity of the brightness temperature ([T.sub.B]) to the sea surface salinity (SSS) is low: 0.5 K/psu for a sea surface temperature (SST) of 20[degrees]C, decreasing to 0.25 K/psu for a SST of 0[degrees]C. Since other variables than SSS influence the [T.sub.B] signal (sea surface temperature, surface roughness and foam), the accuracy of the SSS measurement will degrade unless these effects are properly accounted for. The main objective of the ESA-sponsored Wind and Salinity Experiment (WISE) field experiments has been the improvement of our understanding of the sea state effects on [T.sub.B] at different incidence angles and polarizations. This understanding will help to develop and improve sea surface emissivity models to be used in the SMOS SSS retrieval algorithms. This paper summarizes the main results of the WISE field experiments on sea surface emissivity at L-band and its application to a performance study of multiangular sea surface salinity retrieval algorithms. The processing of the data reveals a sensitivity of [T.sub.B] to wind speed extrapolated at nadir of ~0.23-0.25 K/(m/s), increasing at horizonal (H) polarization up to ~0.5 K/(m/s), and decreasing at vertical (V) polarization down to ~-0.2 K/(m/s) at 65[degrees] incidence angle. The sensitivity of [T.sub.B] to significant wave height extrapolated to nadir is ~1 K/m, increasing at H-polarization up to ~1.5 K/m, and decreasing at V-polarization down to -0.5 K/m at 65[degrees]. A modulation of the instantaneous brightness temperature [T.sub.B](t) is found to be correlated with the measured sea surface slope spectra. Peaks in [T.sub.B](t) are due to foam, which has allowed estimates of the foam brightness temperature and, taking into account the fractional foam coverage, the foam impact on the sea surface brightness temperature. It is suspected that a small azimuthal modulation ~0.2-0.3 K exists for low to moderate wind speeds. However, much larger values (4-5 K peak-to-peak) were registered during a strong storm, which could be due to increased foam. These sensitivities are satisfactorily compared to numerical models, and multiangular [T.sub.B] data have been successfully used to retrieve sea surface salinity. Index Terms--Foam, L-band, radiometry, sea salinity retrieval, sea spectrum, waves, wind.

Published
2004

14. Initial Evaluation of SAR Capabilities in UAV Multicopter Platforms

Author

Universidad de Alicante. Departamento de Física, Ingeniería de Sistemas y Teoría de la Señal, Lort, Marc, Aguasca, Albert, Lopez-Martinez, Carlos, Martínez Marín, Tomás, Universidad de Alicante. Departamento de Física, Ingeniería de Sistemas y Teoría de la Señal, Lort, Marc, Aguasca, Albert, Lopez-Martinez, Carlos, and Martínez Marín, Tomás

Abstract

Airborne synthetic aperture radar (SAR) sensors have been commonly used during the last decades to monitor different phenomena in medium-scale areas of observation, such as object detection and characterization or topographic mapping. The use of unmanned aerial vehicles (UAVs) is a cost-effective solution that offers higher operational flexibility than airborne systems to monitor these types of scenarios. The Universitat Politècnica de Catalunya has developed the first fully polarimetric SAR system at X-band integrated into a small UAV multicopter platform (UAV MP). The sensor, called AiR-based remote sensing, has been integrated into the platform overcoming restrictions of weight, space, robustness, and power consumption. To demonstrate the validity of the developed system, some measurement campaigns have been conducted in the outskirts of Barcelona, Spain.

Published
2018

19. De campañas de medidas a productos de salinidad: un tributo a las contribuciones de Jordi Font a la mision SMOS

Author

Camps, Adriano, Gabarró, Carolina, Vall-llossera, Mercè, Blanch, Sebastià, Aguasca, Albert, Torres, Francesc, Corbella, Ignasi, Duffo, Nuria, Turiel, Antonio, Portabella, Marcos, Ballabrera-Poy, Joaquim, González-Gambau, Verónica, Martínez, Justino, Villarino, Ramón, Enrique, Luís, Monerris, Alessandra, Bosch, Xavier, Sabia, Roberto, Talone, Marco, Piles, Maria, Pablos, Míriam, Valencia, Enric, and This work has been performed under research grants TEC2005-06863-C02-01/TCM, ESP2005-06823-C05 and ESP2007-65667-C04, AYA2008-05906-C02-01/ ESP, AYA2010-22062-C05 and ESP2015-70014-C2- 1-R, and EURYI 2004 award

Subjects
SMOS, radiometría, interferometría, calibración, validación, salinidad, humedad del terreno, hielo marino, GNSS-R, radiometry, interferometry, calibration, validation, salinity, soil moisture, sea ice
Abstract

This article summarizes some of the activities in which Jordi Font, research professor and head of the Department of Physical and Technological Oceanography, Institut de Ciències del Mar (CSIC, Spanish National Research Council) in Barcelona, has been involved as co-Principal Investigator for Ocean Salinity of the European Space Agency Soil Moisture and Ocean Salinity (SMOS) Earth Explorer Mission from the perspective of the Remote Sensing Lab at the Universitat Politècnica de Catalunya. We have probably left out some of his many contributions to salinity remote sensing, but we hope that this review will give an idea of the importance of his work. We focus on the following issues: 1) the new accurate measurements of the sea water dielectric constant, 2) the WISE and EuroSTARRS field experiments that helped to define the geophysical model function relating brightness temperature to sea state, 3) the FROG 2003 field experiment that helped to understand the emission of sea foam, 4) GNSS-R techniques for improving sea surface salinity retrieval, 5) instrument characterization campaigns, and 6) the operational implementation of the Processing Centre of Levels 3 and 4 at the SMOS Barcelona Expert Centre., Este artículo resume algunas de las actividades en las que Jordi Font, profesor de investigación y jefe del Departamento de Física y Tecnología Oceanográfica, del Institut de Ciències del Mar (CSIC) en Barcelona, ha estado desarrollando como co-Investigador Principal de la parte de la misión SMOS de la ESA, una misión Earth Explorer, desde la perspectiva del Remote Sensing Lab, de la Universitat Politècnica de Catalunya. Seguramente, estamos olvidando algunas de sus muchas contribuciones a la teledetección de la salinidad, pero esperamos que esta revisión dé una idea de la importancia de su trabajo. Este artículo se focaliza en los siguientes puntos: 1) las medidas de alta calidad de la constante dieléctrica del agua marina, 2) las campañas de medidas WISE y EuroSTARRS que ayudaron a la definición del modelo geofísico relacionando la temperatura de brillo con el estado del mar, 3) la campaña de medidas FROG 2003 que ayudó a entender la emisión de la espuma marina 4) presentación de las técnicas de GNSS-R para la mejora de la recuperación de la salinidad superficial 5) campañas para la caracterización del instrumento y 6) la implantación del centro de procesado operacional de niveles 3 y 4 en el SMOS Barcelona Expert Centre.

Published
2016
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20. From field experiments to salinity products: a tribute to the contributions of Jordi Font to the SMOS mission

Author

Camps, Adriano, primary, Gabarró, Carolina, additional, Vall-llossera, Mercè, additional, Blanch, Sebastià, additional, Aguasca, Albert, additional, Torres, Francesc, additional, Corbella, Ignasi, additional, Duffo, Nuria, additional, Turiel, Antonio, additional, Portabella, Marcos, additional, Ballabrera-Poy, Joaquim, additional, González-Gambau, Verónica, additional, Martínez, Justino, additional, Villarino, Ramón, additional, Enrique, Luís, additional, Monerris, Alessandra, additional, Bosch, Xavier, additional, Sabia, Roberto, additional, Talone, Marco, additional, Piles, Maria, additional, Pablos, Míriam, additional, and Valencia, Enric, additional

Published
2016
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24. RFID probes for EM field measurements

Author

Capdevila, Santiago, Mubeen Masud, Muhammad, Serrano Calvo, Raquel, Aguasca, Albert, Blanch Boris, Sebastian, Romeu, Jordi, Bolomey, Jean-Charles, Jofre, Luis, Department of Signal Theory and Communications, Universitat Politècnica de Catalunya [Barcelona] (UPC), Royal Institute of Technology [Stockholm] (KTH ), Laboratoire des signaux et systèmes (L2S), Université Paris-Sud - Paris 11 (UP11)-CentraleSupélec-Centre National de la Recherche Scientifique (CNRS), European Association on Antennas and Propagation, and Duchêne, Bernard

Subjects
[SPI.ELEC]Engineering Sciences [physics]/Electromagnetism, [SPI.ELEC] Engineering Sciences [physics]/Electromagnetism, ComputingMilieux_MISCELLANEOUS
Abstract

International audience

Published
2009

25. A polarimetric Ground-based SAR System : First Results at X-Band

Author

Pipia, L., Aguasca, Albert, Fabregas, Xavier, Mallorqui, J.J., Lopez-Martinez, Carlos, Universitat Politècnica de Catalunya [Barcelona] (UPC), Department of Signal Theory and Communications, Institut d'Électronique et des Technologies du numéRique (IETR), Université de Nantes (UN)-Université de Rennes 1 (UR1), Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), Institut National des Sciences Appliquées (INSA)-Université de Rennes (UNIV-RENNES)-Institut National des Sciences Appliquées (INSA)-CentraleSupélec-Centre National de la Recherche Scientifique (CNRS), Université de Nantes (UN)-Université de Rennes (UR)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-CentraleSupélec-Centre National de la Recherche Scientifique (CNRS), and Nantes Université (NU)-Université de Rennes 1 (UR1)

Subjects
ComputingMilieux_MISCELLANEOUS
Abstract

International audience

Published
2005

32. Educación social : revista de intervención socioeducativa

Author

Aguasca, Albert, Pérez Baeza, José Luis, and Mallorquí, Jordi J.

Subjects
deficiente físico, tecnología de control, deficiente mental, tecnología de los medios de comunicación
Abstract

En este artículo se presenta un desarrollo cuya finalidad es poner a disposición de personas con discapacidad un servicio que les permita, ante situaciones de alarma enviar la información de su ubicación geográfica a un centro de control, a la vez que se les ofrece una comunicación de voz y también un seguimiento automático de su posición. Este servicio está pensado para aumentar el grado de autonomía de colectivos con discapacidades psíquicas, físicas o simplemente de personas mayores, que frente a una situación de indisposición, desorientación o pérdida puedan contactar con una mínima intervención con un centro de control. Cataluña ESP

Published
1999

35. Snow Thickness Monitoring Using GNSS Measurements

Author

Rodriguez-Alvarez, Nereida, primary, Aguasca, Albert, additional, Valencia, Enric, additional, Bosch-Lluis, Xavier, additional, Camps, Adriano, additional, Ramos-Perez, Isaac, additional, Park, Hyuk, additional, and Vall-llossera, Merce, additional

Published
2012
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38. Review of the CALIMAS Team Contributions to European Space Agency’s Soil Moisture and Ocean Salinity Mission Calibration and Validation

Author

Camps, Adriano, primary, Font, Jordi, additional, Corbella, Ignasi, additional, Vall-Llossera, Mercedes, additional, Portabella, Marcos, additional, Ballabrera-Poy, Joaquim, additional, González, Verónica, additional, Piles, María, additional, Aguasca, Albert, additional, Acevo, René, additional, Bosch, Xavier, additional, Duffo, Nuria, additional, Fernández, Pedro, additional, Gabarró, Carolina, additional, Gourrion, Jérôme, additional, Guimbard, Sébastien, additional, Marín, Anna, additional, Martínez, Justino, additional, Monerris, Alessandra, additional, Mourre, Baptiste, additional, Pérez, Fernando, additional, Rodríguez, Nereida, additional, Salvador, Joaquín, additional, Sabia, Roberto, additional, Talone, Marco, additional, Torres, Francesc, additional, Pablos, Miriam, additional, Turiel, Antonio, additional, Valencia, Enric, additional, Martínez-Fernández, José, additional, Sánchez, Nilda, additional, Pérez-Gutiérrez, Carlos, additional, Baroncini-Turricchia, Guido, additional, Rius, Antonio, additional, and Ribó, Serni, additional

Published
2012
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50. Ground-Based Polarimetric SAR Interferometry for the Monitoring of Terrain Displacement Phenomena–Part I: Theoretical Description.

Author

Iglesias, Ruben, Aguasca, Albert, Fabregas, Xavier, Mallorqui, Jordi J., Monells, Dani, Lopez-Martinez, Carlos, and Pipia, Luca

Abstract

Ground-based synthetic aperture radar (SAR) (GB-SAR) sensors represent an effective solution for the monitoring of ground displacement episodes. Initially, the most GB-SAR sensors were based on vector network analyzers (VNA). This type of solution, characterized by a slow scanning time comparable to the decorrelation of the troposphere medium, compromised in many cases the quality of final products for the application of persistent scatterer interferomerty (PSI) techniques. The development of GB-SAR sensors based on the use of stepped linear frequency modulated continuous wave (SLFMCW) signals has led to significant improvements during the last years. They have allowed fulfilling the need of temporal homogeneity of the troposphere during the acquisition time and, moreover, they have favored the acquisition of reliable polarimetric SAR (PolSAR) measurements without drastically increasing the scanning time. This fact has boosted the inclusion of polarimetric SAR interferometry (PolInSAR) algorithms in PSI processing chains, which are demonstrating to outperform classical single-polarimetric performances. The objective of this paper is twofold. On the one hand, a general overview of the polarimetric RiskSAR sensor, developed by the Universitat Politècnica de Catalunya (UPC), is put forward as an example of SLFMCW GB-SAR system implementation. On the other hand, a complete theoretical description of ground-based SAR (GB-SAR) interferometry (GB-InSAR) techniques for PSI purposes is widely discussed. The adaptation of the Coherent Pixels Technique to obtain the linear and nonlinear components of ground displacement phenomena is proposed. In the second part of this paper, the displacement maps and time series over two very different scenarios are presented in order to show the feasibility of GB-SAR sensors for terrain displacement monitoring applications. [ABSTRACT FROM PUBLISHER]

Published
2015
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