Now showing items 21-40 of 44

    • Improvement of the ionospheric radio occultation retrievals by means of accurate global ionospheric maps 

      Shao, Yixie; González Casado, Guillermo; Juan Zornoza, José Miguel; Sanz Subirana, Jaume; Rovira Garcia, Adrià (2018-12-22)
      Article
      Restricted access - author's decision
      The Abel inversion method is the classic approach to retrieve electron density profiles from radio occultation measurements, assuming that the electron density is only dependent upon height. In the early 2000s, the total ...
    • Ionosphere/Plasmasphere sounding with ground and space-based GNSS observations 

      González Casado, Guillermo; Juan Zornoza, José Miguel; Sanz Subirana, Jaume; Shao, Yixie (Institute of Electrical and Electronics Engineers (IEEE), 2016)
      Conference report
      Open Access
      Applying a methodology developed and tested in previous studies, the contribution from the ionospheric and plasmaspheric regions to the total electron content (measured by ground receivers) is analyzed. ...
    • Ionospheric and plasmaspheric contribution to the total electron content inferred from ground data and radio-occultation-derived electron density 

      González Casado, Guillermo; Juan Zornoza, José Miguel; Sanz Subirana, Jaume; Rovira Garcia, Adrià; Aragón Angel, Angela (2015)
      Conference report
      Restricted access - publisher's policy
    • Ionospheric and plasmaspheric electron contents inferred from radio occultations and global ionospheric maps 

      González Casado, Guillermo; Juan Zornoza, José Miguel; Sanz Subirana, Jaume; Rovira Garcia, Adrià; Aragón Angel, Angela (2015-07-04)
      Article
      Open Access
      We introduce a methodology to extract the separate contributions of the ionosphere and the plasmasphere to the vertical total electron content, without relying on a fixed altitude to perform that separation. The method ...
    • Ionospheric scintillation model limitations and impact in GNSS-R missions 

      Camps Carmona, Adriano José; González Casado, Guillermo; Juan Zornoza, José Miguel; Hyuk, Park; Barbosa, José (Institute of Electrical and Electronics Engineers (IEEE), 2020)
      Conference report
      Open Access
      The ionosphere impacts radio-wave propagation, notably up to a few GHz. The main applications impacted by the ionosphere are GNSS positioning and timing, Earth Observations (especially low frequency SAR missions e.g. ...
    • Ionospheric scintillation monitoring using GNSS-R? 

      Camps Carmona, Adriano José; Hyuk, Park; Juan Zornoza, José Miguel; Sanz Subirana, Jaume; González Casado, Guillermo; Barbosa, José; Fabbro, V; Lemorton, J; Orús Pérez, Raul (Institute of Electrical and Electronics Engineers (IEEE), 2018)
      Conference report
      Restricted access - publisher's policy
      The characterization of the ionosphere and its impact on the propagation of radio-wave signals has received an increasing interest for satellite communications, Global Navigation Satellite Systems (GNSS) applications (i.e. ...
    • Measuring phase scintillation at different frequencies with conventional GNSS receivers operating at 1 Hz 

      Nguyen, Viet Khoi; Rovira Garcia, Adrià; Juan Zornoza, José Miguel; Sanz Subirana, Jaume; González Casado, Guillermo; Hai Tung, Ta; The Vinh, La (2019-10-01)
      Article
      Open Access
      Ionospheric scintillation causes rapid fluctuations of measurements from Global Navigation Satellite Systems (GNSSs), thus threatening space-based communication and geolocation services. The phenomenon is most intense in ...
    • MÈTODES NUMÈRICS 3 (2n quatrimestre, final) 

      González Casado, Guillermo (Universitat Politècnica de Catalunya, 2010-06-04)
      Exam
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    • MÈTODES NUMÈRICS 3 (convocatòria extraordinària) 

      González Casado, Guillermo (Universitat Politècnica de Catalunya, 2010-07-07)
      Exam
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    • MÈTODES NUMÈRICS 3 (Examen 2n quadrim) 

      González Casado, Guillermo (Universitat Politècnica de Catalunya, 2009-05-22)
      Exam
      Restricted access to the UPC academic community
    • MÈTODES NUMÈRICS 3 (Examen 2n quadrim) 

      González Casado, Guillermo (Universitat Politècnica de Catalunya, 2009-03-27)
      Exam
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    • MÈTODES NUMÈRICS 3 (Examen 2n quadrim) 

      González Casado, Guillermo (Universitat Politècnica de Catalunya, 2008-05-21)
      Exam
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    • Network-based ionospheric gradient monitoring to support GBAS 

      Caamaño Albuerne, María; Felux, Michael; Gerbeth, Daniel; Juan Zornoza, José Miguel; González Casado, Guillermo; Sanz Subirana, Jaume (ION Publications (The Institute of navigation), 2019)
      Conference report
      Open Access
      Ionospheric anomalies, like large ionospheric gradients, might produce a difference between the ionospheric error experienced bythe Ground Based Augmentation System (GBAS) reference station and the aircraft on approach. ...
    • Novel ionospheric activity indicator specifically tailored for GNSS users 

      Sanz Subirana, Jaume; Juan Zornoza, José Miguel; González Casado, Guillermo; Prieto Cerdeira, Roberto; Schlüter, S.; Orús Pérez, Raul (The Institute of Navigation, 2014)
      Conference report
      Restricted access - author's decision
      This work introduces a novel ionospheric activity indicator useful for identifying disturbed periods affecting performance for GNSS users, at regional level. This indicator is based in the “Along Arc TEC Rate (AATR) and ...
    • Origin and modelling of cold dark matter halo properties: IV. Triaxial ellipticity 

      Salvador-Solé, Eduard; Serra, Sinué; Manrique, Alberto; González Casado, Guillermo (2011-04-15)
      External research report
      Open Access
      In the three preceding papers in the series, we presented a model dealing with the global and small-scale structure and kinematics of hierarchically assembled, virialised, collisionless systems, which correctly accounted ...
    • Removing day-boundary discontinuities on GNSS clock estimates: methodology and results 

      Rovira Garcia, Adrià; Juan Zornoza, José Miguel; Sanz Subirana, Jaume; González Casado, Guillermo; Ventura Traveset, Javier; Cacciapuoti, Luigi; Schoenemann, Erik (2021-04)
      Article
      Open Access
      Global navigation satellite system (GNSS) satellites are equipped with very stable atomic clocks that can be used for assess-ing the models and strategies involved in the estimation processes, where the clock estimates ...
    • Revisit the calibration errors on experimental slant total electron content (TEC) determined with GPS 

      Nie, Wenfeng; Xu, Tianhe; Rovira Garcia, Adrià; Juan Zornoza, José Miguel; Sanz Subirana, Jaume; González Casado, Guillermo; Chen, Wu; Xu, Guochang (2018-06-26)
      Article
      Open Access
      The calibration errors on experimental slant total electron content (TEC) determined with global positioning system (GPS) observations is revisited. Instead of the analysis of the calibration errors on the carrier phase ...
    • Synthetic events description, generation and characterization report 

      González Casado, Guillermo; Juan Zornoza, José Miguel; Sanz Subirana, Jaume (2015-02-20)
      External research report
      Open Access
    • TEC Parametric Model validation and Approach to GNSS operational conditions 

      González Casado, Guillermo (2017-05-10)
      External research report
      Open Access
    • The Geodetic Detrending technique: enabling high-accuracy navigation under scintillation 

      Rovira Garcia, Adrià; Juan Zornoza, José Miguel; Sanz Subirana, Jaume; González Casado, Guillermo (Institute of Electrical and Electronics Engineers (IEEE), 2020)
      Conference report
      Restricted access - publisher's policy
      Scintillation is a particular type of space weather perturbation occurred when the signals from the Global Navigation Satellite System (GNSS) traverse irregularities in the ionosphere; the upper layer of the Earth atmosphere. ...