Now showing items 21-40 of 61

    • Impact of amplitude calibration errors on SMOS global images 

      Durán Martínez, Israel; Corbella Sanahuja, Ignasi; Torres Torres, Francisco; Duffo Ubeda, Núria; Oliva, Roger; Martín Neira, Manuel (Institute of Electrical and Electronics Engineers (IEEE), 2016)
      Conference report
      Restricted access - publisher's policy
      Some of the artifacts observed in SMOS brightness temperature images are originated in an inconsistency between correlation and antenna temperature calibration errors, which produces a multiplicative bias that scales with ...
    • Impact of correlator efficiency errors on SMOS land-sea contamination 

      Corbella Sanahuja, Ignasi; Durán Martínez, Israel; Wu, Lin; Torres Canals, Francesc; Duffo Ubeda, Núria; Khazaal, Ali; Martín Neira, Manuel (2015-09-01)
      Article
      Open Access
      Land-sea contamination observed in Soil Moisture and Ocean Salinity (SMOS) brightness temperature images is found to have two main contributions: the floor error inherent of image reconstruction and a multiplicative error ...
    • In-orbit validations of SMOS full polarimetric equations 

      Torres Torres, Francisco; Corbella Sanahuja, Ignasi; Wu, Lin; Duffo Ubeda, Núria; Delwart, Steven; Martín Neira, Manuel (Institute of Electrical and Electronics Engineers (IEEE), 2013)
      Conference report
      Restricted access - publisher's policy
      This paper analyzes the consistency of SMOS fully polarimetric measurement mode by comparing measured data over the ocean with the expected results. These last are based on an accurate ocean model provided by LOCEAN and ...
    • Integration of MIRAS breadboard and future activities 

      Martín Neira, Manuel; Goutoule, J.M.; Knight, A.; Claude, J.; Bará Temes, Francisco Javier; Camps Carmona, Adriano José; Torres Torres, Francisco; Corbella Sanahuja, Ignasi; Lannes, A.; Anterrieu, E.; Laursen, B.; Skou, N. (1996)
      Conference report
      Open Access
      The European Space Agency (ESA) is conducting a feasibility study on MIRAS, a Microwave Imaging Radiometer using two dimensional aperture synthesis, for the mapping of soil moisture and ocean salinity from space. An aircraft ...
    • Millimeter-wave aperture synthesis for remote sensing of the Earth 

      Harvey, Andrew R.; Greenaway, Alain H.; Camps Carmona, Adriano José; Bará Temes, Francisco Javier; Torres Torres, Francisco; Corbella Sanahuja, Ignasi; Martín Neira, Manuel (1998)
      Conference report
      Open Access
      Millimetre-wave radiometry of the earth's surface from Low Earth Orbit (LEO) with a resolution of a few km requires antenna apertures several metres across and sub-second scanning times. Fulfilling these requirements with ...
    • Millimeter-wave aperture synthesis radiometry for snow and ice mapping 

      Harvey, A.R.; Greenaway, A.H.; Camps Carmona, Adriano José; Corbella Sanahuja, Ignasi; Torres Torres, Francisco; Bará Temes, Francisco Javier; Martín Neira, Manuel (1999)
      Conference report
      Open Access
      An outline design for a dual-band mm-wave polarimetric SAIR has been presented and is considered to be tractable. The envisaged application is for snow and ice mapping and ocean wind vector measurement. The vastly increased ...
    • MIRAS calibration and performance: results from the SMOS in-orbit commissioning phase 

      Corbella Sanahuja, Ignasi; Torres Torres, Francisco; Duffo Ubeda, Núria; González Gambau, Veronica; Pablos Hernández, Miriam; Durán Martínez, Israel; Martín Neira, Manuel (IEEE Press. Institute of Electrical and Electronics Engineers, 2011-09)
      Article
      Restricted access - publisher's policy
      After the successful launching of the Soil Moisture and Ocean Salinity satellite in November 2009, continuous streams of data started to be regularly downloaded and made available to be processed. The first six months of ...
    • MIRAS End-to-End Calibration: Application to SMOS L1 Processor 

      Corbella Sanahuja, Ignasi; Torres Torres, Francisco; Camps Carmona, Adriano José; Colliander, Andreas; Martín Neira, Manuel; Ribó Vedrilla, Serni; Rautiainen, Kimmo; Duffo Ubeda, Núria; Vall-Llossera Ferran, Mercedes Magdalena (IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC, 2005-05-31)
      Article
      Open Access
      End-to-end calibration of the Microwave Imaging Radiometer by Aperture Synthesis (MIRAS) radiometer refers to processing the measured raw data up to dual-polarization brightness temperature maps over the earth's surface, ...
    • MIRAS end-to-end calibration: application to SMOS L1 processor 

      Vall-Llossera Ferran, Mercedes Magdalena; Corbella Sanahuja, Ignasi; Torres Torres, Francisco; Camps Carmona, Adriano José; Colliander, A; Martín Neira, Manuel; Ribó Vedrilla, Serni; Rautiainen, K; Duffo Ubeda, Núria (IEEE Press. Institute of Electrical and Electronics Engineers, 2005-05)
      Article
      Open Access
      End-to-end calibration of the Microwave Imaging Radiometer by Aperture Synthesis (MIRAS) radiometer refers to processing the measured raw data up to dual-polarization brightness temperature maps over the earth's surface, ...
    • Mitigation of cross-polar antenna pattern errors in SMOS: simplified approach 

      Durán Martínez, Israel; Torres Torres, Francisco; Corbella Sanahuja, Ignasi; Duffo Ubeda, Núria; Lin, Wu; Martín Neira, Manuel (Institute of Electrical and Electronics Engineers (IEEE), 2016)
      Conference report
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      This paper analyzes a simplified image reconstruction method that exclusively takes into account the dominant antenna pattern terms to model image inversion artifacts and mitigate SMOS polarimetric spatial bias over the ...
    • Modeling and analysis of GNSS-R waveforms sample-to-sample correlation 

      Martín Alemany, Francisco; D'Addio, Salvatore; Camps Carmona, Adriano José; Martín Neira, Manuel (2014-05-01)
      Article
      Restricted access - publisher's policy
      The exploitation of global navigation satellite systems Earth-reflected signals to perform ocean mesoscale altimetry from space has been originally proposed at the beginning of the 1990s. This technique is generally defined as
    • New methodology for the Faraday rotation angle retrieval in the SMOS field of view 

      Rubino, Roselena; Duffo Ubeda, Núria; González Gambau, Verónica; Torres Torres, Francisco; Corbella Sanahuja, Ignasi; Martín Neira, Manuel (Institute of Electrical and Electronics Engineers (IEEE), 2018)
      Conference lecture
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      In this work, a new methodology to estimate the Faraday Rotation Angle (FRA) from SMOS full-pol brightness temperature is presented. This approach is focused on retrieving the Vertical Total Electron Content (VTEC) and ...
    • Ocean salinity observations with SMOS mission 

      Martín Neira, Manuel; Font Capafons, Josep; Srokerz, M; Corbella Sanahuja, Ignasi; Camps Carmona, Adriano José (IEEE Piscataway, 2000)
      Conference report
      Open Access
      The purpose of this paper is to present the capabilities of SMOS (Soil Moisture and Ocean Salinity mission) for the global mapping of ocean salinity from space. SMOS has been selected by the European Space Agency as the ...
    • On-ground characterization of the SMOS payload 

      Corbella Sanahuja, Ignasi; Torres Torres, Francisco; Duffo Ubeda, Núria; Martín Neira, Manuel; González Gambau, Veronica; Camps Carmona, Adriano José; Vall-Llossera Ferran, Mercedes Magdalena (IEEE Press. Institute of Electrical and Electronics Engineers, 2009-09)
      Article
      Open Access
      The on-ground characterization of the synthetic aperture radiometer onboard the Soil Moisture and Ocean Salinity mission is described. Characterization includes basic functionality, internal calibration, thermal cycling, ...
    • One-point microwave radiometer calibration 

      Corbella Sanahuja, Ignasi; Torres Torres, Francisco; Closa Soteras, Josep; Duffo Ubeda, Núria; Durán Martínez, Israel; González Gambau, Verónica; Martín Neira, Manuel (2020-03-01)
      Article
      Open Access
      A method for internally calibrating microwave total power radiometers by using only one level of noise injection is presented. It is based on having a previous accurate characterization of the receiver noise temperature, ...
    • Optimization and performance analysis of interferometric GNSS-R altimeters: application to the PARIS IoD mission 

      Camps Carmona, Adriano José; Hyuk, Park; Valencia Domènech, Enric; Pascual Biosca, Daniel; Martín Alemany, Francisco; Rius Jordán, Antonio; Ribó Vedrilla, Serni; Benito, Javier; Andres-Beivide, Ana; Saameno, Paula; Staton, Gavin; Martín Neira, Manuel; D'Addio, Salvatore; Willemsen, Philip (2014-05-01)
      Article
      Restricted access - publisher's policy
      Reflectometry using Global Navigation Satellite System's signals (GNSS-R) of opportunity was originally conceived in the early 1990 s for mesoscale altimetry, and since then, many studies have shown its applicability to ...
    • PARIS interferometric technique proof of concept: sea surface altimetry measurements 

      Rius, A.; Fabra Cervellera, Fran; Ribó Vedrilla, Serni; Arco Fernandez, Juan Carlos; Oliveras, S.; Cardellach, Estel; Camps Carmona, Adriano José; Nogués Correig, O.; Kainulainen, J.; Rohue, E.; Martín Neira, Manuel (Institute of Electrical and Electronics Engineers (IEEE), 2012)
      Conference report
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      We report preliminary results of an aircraft experiment aimed to proof the PARIS Interferometric Technique. The experiment was performed in the Gulf of Finland during a two hours flight.We installed a PARIS Interferometric ...
    • Performance of a spatial error correction technique in SMOS brightness temperature images 

      Wu, Lin; Torres Torres, Francisco; Corbella Sanahuja, Ignasi; Duffo Ubeda, Núria; Martín Neira, Manuel (Institute of Electrical and Electronics Engineers (IEEE), 2012)
      Conference report
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      Soil Moisture and Ocean Salinity (SMOS) brightness temperature synthesized images are obtained after a comprehensive calibration and error correction procedure. However, the final images are stil ...
    • Practical issues on SMOS single antenna patterns 

      Wu, Lin; Durán Martínez, Israel; Torres Torres, Francisco; Corbella Sanahuja, Ignasi; Duffo Ubeda, Núria; Closa, Josep; Manrique, Rodrigo; Garcia, Quiterio; Oliva Balagué, Roger; Martín Neira, Manuel (2014)
      Conference report
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      This paper provides a wrap-up of some of the activities undertaken by SMOS L1 team to fine tune the instrument calibration and modeling that eventually has resulted into a SMOS full-polarimetric measurement and image ...
    • Radiometric performance of SMOS full polarimetric imaging 

      Wu, Lin; Torres Torres, Francisco; Corbella Sanahuja, Ignasi; Duffo Ubeda, Núria; Durán Martínez, Israel; Vall-Llossera Ferran, Mercedes Magdalena; Camps, Adiano; Delwart, Steven; Martín Neira, Manuel (2013-11)
      Article
      Restricted access - publisher's policy
      This work has been conducted in the framework of several projects devoted to assess the performance of the Soil Moisture and Ocean Salinity (SMOS) mission full-pol measurement mode. Since its launch in November 2009, SMOS ...