Calibration Introduction

In order to maintain the highest possible data reliability and stability, PROBA-V observations were continuously monitored and corrected when required. The observations are calibrated and monitored on geometric and radiometric quality, using sophisticated methods:

  • Radiometric calibration is performed using an automated Cal/Val facility, evaluating the absolute calibration coefficients and inter-band calibration accuracy through three independent vicarious calibration methods:
    • Absolute calibration over the Libya-4 desert site and Rayleigh calibration zones
    • Inter-band calibration over Deep Convective Clouds
    • Instrument stability monitoring using lunar observations
  • Geometric calibration is done by an autonomous in-flight software package to estimate various geometric parameters and to update the Instrument Calibration Parameter (ICP) files when necessary, using the Landsat Global Land Survey (GLS) 2010 Ground Control Point (GCP) dataset.

More details on the radiometric and geometric calibration and validation methods are given in the respective subsections.

The radiometric calibration was updated in the 2nd reprocessing campaign after the mission ended. The changes in the radiometric calibration of PROBA-V Collection 2 can be found in the PROBA-V C2 Algorithms Change Document.