Different processing levels of SIR-C/X-SAR radar data for the correction of relief induced distortions in mountainous areas
The third Shuttle Imaging Radar (SIR-C) was the first multifrequency and multipolarization SAR system monitoring the Earth from space. The availability of several frequencies and polarizations offers the opportunity of low level radiometric enhancement of SAR data via principal component or ratio analysis to correct the relief induced distortions of SAR images in mountainous areas. The potential of this method is presented based on the example of the Timna Valley in the south of Israel. Especially in areas where no DEM for the correction is available the method to be presented has a high application potential. For comparison the SIR-C/X-SAR data were also corrected conventionally on the basis of the local incidence angle derived via a DEM. This correction technique has the great advantage of getting real backscatter values for each frequency and polarization.