Retrieval of surface reflectance from Hyperion radiance data

Abstract

Surface reflectance was retrieved from Hyperion data by a procedure involving data preprocessing steps and atmospheric correction. Several steps are required to remove sensor artifacts in the spectral and spatial domain. These artifacts include a spatial shift in the short-wave infrared (SWIR) data, an along-track striping, a spatial misalignment of the visible near infrared (VNIR) and SWIR data, and a cross-track spectral (smile/frown) effect. A look-up table approach in combination with the radiance transfer code MODTRAN4.2 was applied to preprocessed at-sensor radiance data to retrieve surface reflectance. Results indicate that the spectral calibration data provided do not achieve a proper positioning of the bands' centre wavelengths. Wavelength shifts of up to 1 nm in the VNIR and up to 3 nm in the SWIR remain. This can be seen especially at wavelengths affected by strong gaseous absorptions.