Exploració per tema "geophysical techniques"

Ara es mostren els items 1-11 de 11

    • A two-dimensional doppler-radiometer for earth observation 

      Camps Carmona, Adriano José; Swift, Calvin T. (IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC, 2001-07-31)
      Article
      Accés obert
      Compared to synthetic aperture radars (SARs), the angular resolution of microwave radiometers is quite poor. Traditionally, it has been limited by the physical size of the antenna. However, the angular resolution can be ...

    • Compensation of elevation angle variations in polarimetric brightness temperature measurements from airborne microwave radiometers 

      Corbella Sanahuja, Ignasi; Gasiewski, A.J.; Klein, Marian; Piepmeier, Jeffrey R. (IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC, 2001-01-31)
      Article
      Accés obert
      This paper presents a method for compensating the elevation angle fluctuations occurring in airborne radiometry due to aircraft roll and pitch. The correction is based on a radiative transfer model, and is demonstrated by ...

    • Indoor experiments on polarimetric SAR interferometry 

      Sagués Piella, Lluís; López-Sánchez, Juan Manuel; Fortuny, Joaquim; Fabregas Canovas, Francisco Javier; Broquetas Ibars, Antoni; Sieber, A. J. (IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC, 2000-03-31)
      Article
      Accés obert
      A coherence optimization method, which makes use of polarimetry to enhance the quality of SAR interferograms, has been experimentally tested under laboratory conditions in an anechoic chamber. By carefully selecting the ...

    • On-board phase and modulus calibration of large aperture synthesis radiometers: study applied to miras. 

      Torres Torres, Francisco; Camps Carmona, Adriano José; Bará Temes, Francisco Javier; Corbella Sanahuja, Ignasi; Ferrero Pintor, Roberto (IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC, 1996-07-01)
      Article
      Accés obert
      On-board calibration of bidimensional aperture synthesis radiometers with a large number of antennas by the standard correlated noise injection method is technologically very critical because of the stringent requirements ...

    • Radiometric sensitivity computation in aperture synthesis interferometric radiometry 

      Camps Carmona, Adriano José; Corbella Sanahuja, Ignasi; Bará Temes, Francisco Javier; Torres Torres, Francisco (IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC, 1998-03-01)
      Article
      Accés obert
      This paper is concerned with the radiometric sensitivity computation of an aperture synthesis interferometric radiometer devoted to Earth observation. The impact of system parameters and the use of simultaneous redundant ...

    • Radiometric Sensitivity Computation in Aperture Synthesis Interferometric Radiometry 

      Camps Carmona, Adriano José; Corbella Sanahuja, Ignasi; Bará Temes, Francisco Javier; Torres Torres, Francisco (IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC, 1998-03-31)
      Article
      Accés obert
      This paper is concerned with the radiometric sensitivity computation of an aperture synthesis interferometric radiometer devoted to Earth observation. The impact of system parameters and the use of simultaneous redundant ...

    • Refined estimation of time-varying baseline errors in airborne SAR interferometry 

      Reigber, Andreas; Prats Iraola, Pau; Mallorquí Franquet, Jordi Joan (IEEE, 2006-01-31)
      Article
      Accés obert
      The processing of airborne synthetic aperture radar (SAR) data requires a precise compensation of the deviations of the platform movement from a straight line. This is usually carried out by recording the trajectory with ...

    • RF interference analisys in aperture synthesis interferometric radiometers: Application to L-band MIRAS instrument 

      Camps Carmona, Adriano José; Corbella Sanahuja, Ignasi; Torres Torres, Francisco; Bará Temes, Francisco Javier; Capdevila Vives, Joan (IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC, 2000-03-31)
      Article
      Accés obert
      Current spaceborne radiometers do not achieve the required spatial resolution demanded by the scientific community due to antenna-size technological limitations. In recent years, several space agencies have been studying ...

    • Synthesis, construction, and validation of a fractal surface 

      Ruello, Giuseppe; Blanco Sánchez, Pablo; Iodice, Antonio; Mallorquí Franquet, Jordi Joan; Riccio, Daniele; Broquetas Ibars, Antoni; Franceschetti, Girogio (IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC, 2006-06-30)
      Article
      Accés obert
      Fractal geometry provides reliable models to describe geometrical properties of natural surfaces. Therefore, their use in the electromagnetic scattering methods deserves careful research. In order to have complete insight ...

    • The correlation of visibility errors and its impact on the radiometric resolution of an aperture synthesis radiometer 

      Bará Temes, Francisco Javier; Camps Carmona, Adriano José; Torres Torres, Francisco; Corbella Sanahuja, Ignasi (IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC, 2000-09-30)
      Article
      Accés obert
      The correlation between the visibility samples' noise of an aperture synthesis radiometer are required for the computation of the recovered temperature noise of a given pixel and of the improvement introduced by baseline ...

    • The processing of hexagonally sampled signals with standard rectangular techniques: application to 2D large aperture synthesis interferometric radiometers 

      Camps Carmona, Adriano José; Bará Temes, Francisco Javier; Corbella Sanahuja, Ignasi; Torres Torres, Francisco (IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC, 1997-01-31)
      Article
      Accés obert
      In Earth observation programs there is a need of passive low frequency (L-band) measurements to monitor soil moisture and ocean salinity with high spatial resolution 10-20 km, a radiometric resolution of 1 K and a revisit ...