Now showing items 1-19 of 19

  • A general analysis of the impact of digitization in microwave correlation radiometers 

    Bosch Lluís, Xavier; Ramos Pérez, Isaac; Camps Carmona, Adriano José; Rodríguez Álvarez, Nereida; Valencia Domènech, Enric; Hyuk, Park (2011-06)
    Article
    Open Access
    This study provides a general framework to analyze the effects on correlation radiometers of a generic quantization scheme and sampling process. It reviews, unifies and expands several previous works that focused on these ...
  • Advanced architectures for real-time delay-doppler map GNSS-reflectometers: the GPS reflectometer instrument for PAU (griPAU) 

    Valencia Domènech, Enric; Camps Carmona, Adriano José; Marchán Hernández, Juan Fernando; Bosch Lluís, Xavier; Rodríguez Álvarez, Nereida; Ramos Pérez, Isaac (2010-07-15)
    Article
    Restricted access - publisher's policy
    In recent years Global Navigation Satellite System’s signals Reflectometry (GNSS-R) has stood as a potential powerful remote sensing technique to derive scientifically relevant geophysical parameters such as ocean altimetry, ...
  • Altimetry study performed using an airborne GNSS-reflectometer 

    Rodríguez Álvarez, Nereida; Acevo Herrera, René; Aguasca Solé, Alberto; Valencia Domènech, Enric; Camps Carmona, Adriano José; Vall-Llossera Ferran, Mercedes Magdalena; Bosch Lluís, Xavier; Ramos Pérez, Isaac (2010)
    Conference lecture
    Open Access
    The Global Navigation Satellite Signals Reflections (GNSSR)techniques have been widely used for remote sensing purposes retrieving geophysical parameters over different types of surfaces. Over the ocean, altimetry or sea ...
  • Calibration, performance, and imaging tests of a fully digital synthetic aperture interferometer radiometer 

    Ramos Pérez, Isaac; Forte Veliz, Giuseppe Francesco; Camps Carmona, Adriano José; Bosch Lluís, Xavier; Valencia Domènech, Enric; Rodríguez Álvarez, Nereida; Hyuk, Park; Vall-Llossera Ferran, Mercedes Magdalena (2012-06-28)
    Article
    Restricted access - publisher's policy
    This work presents the calibration, characterization, and imaging tests of the Passive Advanced Unit-Synthetic Aperture instrument (PAU-SA). PAU-SA is a fully digital -shaped two-dimensional synthetic aperture interferometric ...
  • Common mathematical framework for real and synthetic aperture by interferometry radiometers 

    Bosch Lluís, Xavier; Ramos Pérez, Isaac; Camps Carmona, Adriano José; Rodríguez Álvarez, Nereida; Valencia Domènech, Enric; Hyuk, Park (Institute of Electrical and Electronics Engineers (IEEE), 2014-01)
    Article
    Restricted access - publisher's policy
    This work focuses on the relationship between real and synthetic aperture radiometers giving a general and common mathematical framework for both of them. It will be demonstrated that a real aperture radiometer array ...
  • Contributions to earth observation using gnss-r opportunity signals 

    Rodríguez Álvarez, Nereida (Universitat Politècnica de Catalunya, 2011-12-22)
    Doctoral thesis
  • Land monitoring using GNSS-R techniques: a review of recent advances 

    Camps Carmona, Adriano José; Rodríguez Álvarez, Nereida; Valencia Domènech, Enric; Forte Veliz, Giuseppe Francesco; Ramos Pérez, Isaac; Alonso Arroyo, Alberto; Bosch Lluís, Xavier (Institute of Electrical and Electronics Engineers (IEEE), 2013)
    Conference report
    Restricted access - publisher's policy
    Soil moisture is required to improve meteorological and climate predictions. Global soil moisture maps are nowadays produced daily from SMOS satellite data, with a basic spatial resolution of ~50 km. Recently, using data ...
  • New instrument concepts for ocean sensing: analysis of the PAU-radiometer 

    Camps Carmona, Adriano José; Bosch Lluís, Xavier; Ramos Pérez, Isaac; Marchán Hernández, Juan Fernando; Izquierdo Fernandez, Benjamin; Rodríguez Álvarez, Nereida (IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC, 2007-10-31)
    Article
    Open Access
    Sea surface salinity can be remotely measured by means of L-band microwave radiometry. However, the brightness temperature also depends on the sea surface temperature and on the sea state, which is probably today one of ...
  • Ocean monitoring using GNSS-R techniques and microwave radiometry: The pau instrument concept 

    Camps, Adriano; Bosch, Xavier; Ramos Pérez, Isaac; Marchán Hernández, Juan Fernando; Valencia Domènech, Enric; Rodríguez Álvarez, Nereida (SARTI (Technological Development Centre of Remote Acquisition and Data processing Systems), 2010-03-10)
    Article
    Open Access
  • Ocean surface's scattering coefficient retrieval by delay-doppler map inversion 

    Valencia Domènech, Enric; Camps Carmona, Adriano José; Marchán Hernández, Juan Fernando; Hyuk, Park; Bosch Lluís, Xavier; Rodríguez Álvarez, Nereida; Ramos Pérez, Isaac (2011-07)
    Article
    Restricted access - publisher's policy
    Global navigation satellite system reflectometry of signals is a promising technique to remotely sense a number of Earth’s geophysical parameters, and it has been proposed for ocean monitoring applications such as mesoscale ...
  • On the use of GNSS-R data to correct L-band brightness temperatures for sea-state effects: results of the ALBATROSS field experiments 

    Valencia Domènech, Enric; Camps Carmona, Adriano José; Bosch Lluís, Xavier; Rodríguez Álvarez, Nereida; Ramos Pérez, Isaac; Eugenio, Francisco Javier; Marcello, Javier (IEEE Press. Institute of Electrical and Electronics Engineers, 2011-09)
    Article
    Restricted access - publisher's policy
    Sea surface salinity is a key oceanographic parameter that can be measured by means of L-band microwave radiometry. The measured brightness temperatures over the ocean are influenced by the sea state, which can entirely ...
  • Optimum intercalibration time in synthetic aperture interferometric radiometers: application to SMOS 

    Ramos Pérez, Isaac; Bosch Lluís, Xavier; Camps Carmona, Adriano José; González Gambau, Veronica; Rodríguez Álvarez, Nereida; Valencia Domènech, Enric; Hyuk, Park; Vall-Llossera Ferran, Mercedes Magdalena; Forte Veliz, Giuseppe Francesco (2012)
    Article
    Restricted access - publisher's policy
    Interpolation strategies for calibration of the Soil Moisture and Ocean Salinity (SMOS) mission of the European Space Agency are tested and compared. Calibration strategy (how and how often) is critical in achieving the ...
  • PAU instrument aboard INTA MicroSat-1: A GNSS-R demonstration mission for sea state correction in L-band radiometry 

    Rius, Antonio; Angulo, Manuel; Chavero, Sergio; Martinez, Pedro; Galindo, Juan Jose; Mollfulleda, Antonio; Camps Carmona, Adriano José; Marchán Hernández, Juan Fernando; Valencia Domènech, Enric; Ramos Pérez, Isaac; Bosch Lluís, Xavier; Rodríguez Álvarez, Nereida; Hyuk, Park; Alcayde Egea, Antonio (IEEE, 2011)
    Conference lecture
    Restricted access - publisher's policy
    Global Navigation Satellite System (GNSS) Reflectometry was originally proposed for mesoscale altimetry, but today its feasibility for sea state, soil moisture, vegetation and snow height has already been demonstrated. ...
  • PAU-SA: a synthetic aperture interferometric radiometer test bed for potential improvements in future missions 

    Ramos Pérez, Isaac; Camps Carmona, Adriano José; Bosch Lluís, Xavier; Rodríguez Álvarez, Nereida; Valencia Domènech, Enric; Hyuk, Park; Forte Veliz, Giuseppe Francesco; Vall-Llossera Ferran, Mercedes Magdalena (2012-06)
    Article
    Open Access
    The Soil Moisture and Ocean Salinity (SMOS) mission is an Earth Explorer Opportunity mission from the European Space Agency (ESA). Its goal is to produce global maps of soil moisture and ocean salinity using the Microwave ...
  • Snow monitoring using GNSS-R techniques 

    Rodríguez Álvarez, Nereida; Aguasca Solé, Alberto; Valencia Domènech, Enric; Bosch Lluís, Xavier; Ramos Pérez, Isaac; Hyuk, Park; Camps Carmona, Adriano José; Vall-Llossera Ferran, Mercedes Magdalena (IEEE, 2011)
    Conference report
    Restricted access - publisher's policy
    GNSS-R techniques are currently being studied to remotely sense a number of geophysical parameters over different types of surfaces [1-6]. The Interference Pattern Technique (IPT) is based on the measurement of the ...
  • Study of maize plants effects in the retrieval of soil moisture using the interefence Ppttern GNSS-R technique 

    Rodríguez Álvarez, Nereida; Bosch Lluís, Xavier; Acevo Herrera, René; Aguasca Solé, Alberto; Camps Carmona, Adriano José; Vall-Llossera Ferran, Mercedes Magdalena; Ramos Pérez, Isaac; Valencia Domènech, Enric (2010)
    Conference lecture
    Open Access
    The use of Global Navigation Satellite Signals Reflections (GNSS-R) techniques to retrieve geophysical parameters from surfaces has been increased in the recent years. These techniques have resulted in suitable tools to ...
  • El uso de señales de oportunidad GPS para observación de la Tierra 

    Camps, Adriano; Marchán-Hernández, Juan Fernando; Rodríguez Álvarez, Nereida; Bosch, Xavier; Valencia i Domènech, Enric; Ramos Pérez, Isaac (Escola Tècnica Superior d'Enginyers de Telecomunicació de Barcelona, 2010)
    Article
    Open Access
  • Validation and experimental tests of the PAU-synthetic aperture radiometer 

    Ramos Pérez, Isaac; Forte Veliz, Giuseppe Francesco; Camps Carmona, Adriano José; Bosch Lluís, Xavier; Rodríguez Álvarez, Nereida; Valencia Domènech, Enric; Hyuk, Park; Vall-Llossera Ferran, Mercedes Magdalena (Institute of Electrical and Electronics Engineers (IEEE), 2012)
    Conference report
    Restricted access - publisher's policy
    This paper presents calibration and the radiometric performance of the Passive Advanced Unit Synthetic Aperture (PAU-SA) in order to verify the instrument's characterization.
  • Vegetation water content estimation using GNSS measurements 

    Rodríguez Álvarez, Nereida; Bosch Lluís, Xavier; Camps Carmona, Adriano José; Ramos Pérez, Isaac; Valencia Domènech, Enric; Hyuk, Park; Vall-Llossera Ferran, Mercedes Magdalena (2012-03)
    Article
    Restricted access - publisher's policy
    Global Navigation Satellite Systems (GNSS) opportunity signals reflected at or near the Earth's surface have already shown their potential to perform retrievals of a number of geophysical parameters. Radio occultations ...